Tag Archives: Donald Ingber

Visualization of RNA structures at near-atomic resolution enabled by nanotechnology

The illustration that accompanies the research is both fascinating and baffling as its caption,

Caption: This illustration is inspired by the Paleolithic rock painting in the Lascaux cave, signifying the acronym of our method, ROCK. Figuratively, the patterns of the rock art in the background (brown) are the 2D projections of the engineered dimeric construct of the Tetrahymena group I intron, while the main object in the front (blue) is the reconstructed 3D cryo-EM map of the dimer, with one monomer in focus and refined to the high resolution that allowed the collaborators to build an atomic model of the RNA. Credit: Wyss Institute at Harvard University

This May 2, 2022 news item on ScienceDaily announces the research into RNA molecules made possible by ROCK (the technology being illustrated in the above),

We live in a world made and run by RNA [ribonucleic acid], the equally important sibling of the genetic molecule DNA. In fact, evolutionary biologists hypothesize that RNA existed and self-replicated even before the appearance of DNA and the proteins encoded by it. Fast forward to modern day humans: science has revealed that less than 3% of the human genome is transcribed into messenger RNA (mRNA) molecules that in turn are translated into proteins. In contrast, 82% of it is transcribed into RNA molecules with other functions many of which still remain enigmatic.

To understand what an individual RNA molecule does, its 3D structure needs to be deciphered at the level of its constituent atoms and molecular bonds. Researchers have routinely studied DNA and protein molecules by turning them into regularly packed crystals that can be examined with an X-ray beam (X-ray crystallography) or radio waves (nuclear magnetic resonance). However, these techniques cannot be applied to RNA molecules with nearly the same effectiveness because their molecular composition and structural flexibility prevent them from easily forming crystals.

Now, a research collaboration led by Wyss Core Faculty member Peng Yin, Ph.D. at the Wyss Institute for Biologically Inspired Engineering at Harvard University, and Maofu Liao, Ph.D. at Harvard Medical School (HMS), has reported a fundamentally new approach to the structural investigation of RNA molecules. ROCK, as it is called, uses an RNA nanotechnological technique that allows it to assemble multiple identical RNA molecules into a highly organized structure, which significantly reduces the flexibility of individual RNA molecules and multiplies their molecular weight. Applied to well-known model RNAs with different sizes and functions as benchmarks, the team showed that their method enables the structural analysis of the contained RNA subunits with a technique known as cryo-electron microscopy (cryo-EM). Their advance is reported in Nature Methods.

A May 2, 2022 Wyss Institute for Biologically Inspired Engineering at Harvard University news release (also on EurekAlert) by Benjamin Boettner, which originated the news item, delves further into the imaging technology, Note: Links have been removed,

“ROCK is breaking the current limits of RNA structural investigations and enables 3D structures of RNA molecules to be unlocked that are difficult or impossible to access with existing methods, and at near-atomic resolution,” said Yin, who together with Liao led the study. “We expect this advance to invigorate many areas of fundamental research and drug development, including the burgeoning field of RNA therapeutics.” Yin also is a leader of the Wyss Institute’s Molecular Robotics Initiative and Professor in the Department of Systems Biology at HMS.

Gaining control over RNA

Yin’s team at the Wyss Institute has pioneered various approaches that enable DNA and RNA molecules to self-assemble into large structures based on different principles and requirements, including DNA bricks and DNA origami. They hypothesized that such strategies could also be used to assemble naturally occurring RNA molecules into highly ordered circular complexes in which their freedom to flex and move is highly restricted by specifically linking them together. Many RNAs fold in complex yet predictable ways, with small segments base-pairing with each other. The result often is a stabilized “core” and “stem-loops” bulging out into the periphery. 

“In our approach we install ‘kissing loops’ that link different peripheral stem-loops belonging to two copies of an identical RNA in a way that allows a overall stabilized ring to be formed, containing multiple copies of the RNA of interest,” said Di Liu, Ph.D., one of two first-authors and a Postdoctoral Fellow in Yin’s group. “We speculated that these higher-order rings could be analyzed with high resolution by cryo-EM, which had been applied to RNA molecules with first success.”

Picturing stabilized RNA

In cryo-EM, many single particles are flash-frozen at cryogenic temperatures to prevent any further movements, and then visualized with an electron microscope and the help of computational algorithms that compare the various aspects of a particle’s 2D surface projections and reconstruct its 3D architecture. Peng and Liu teamed up with Liao and his former graduate student François Thélot, Ph.D., the other co-first author of the study. Liao with his group has made important contributions to the rapidly advancing cryo-EM field and the experimental and computational analysis of single particles formed by specific proteins.

“Cryo-EM has great advantages over traditional methods in seeing high-resolution details of biological molecules including proteins, DNAs and RNAs, but the small size and moving tendency of most RNAs prevent successful determination of RNA structures. Our novel method of assembling RNA multimers solves these two problems at the same time, by increasing the size of RNA and reducing its movement,” said Liao, who also is Associate Professor of Cell Biology at HMS. “Our approach has opened the door to rapid structure determination of many RNAs by cryo-EM.” The integration of RNA nanotechnology and cryo-EM approaches led the team to name their method “RNA oligomerization-enabled cryo-EM via installing kissing loops” (ROCK).

To provide proof-of-principle for ROCK, the team focused on a large intron RNA from Tetrahymena, a single-celled organism, and a small intron RNA from Azoarcus, a nitrogen-fixing bacterium, as well as the so-called FMN riboswitch. Intron RNAs are non-coding RNA sequences scattered throughout the sequences of freshly-transcribed RNAs and have to be “spliced” out in order for the mature RNA to be generated. The FMN riboswitch is found in bacterial RNAs involved in the biosynthesis of flavin metabolites derived from vitamin B2. Upon binding one of them, flavin mononucleotide (FMN), it switches its 3D conformation and suppresses the synthesis of its mother RNA.  

“The assembly of the Tetrahymena group I intron into a ring-like structure made the samples more homogenous, and enabled the use of computational tools leveraging the symmetry of the assembled structure. While our dataset is relatively modest in size, ROCK’s innate advantages allowed us to resolve the structure at an unprecedented resolution,” said Thélot. “The RNA’s core is resolved at 2.85 Å [one Ångström is one ten-billions (US) of a meter and the preferred metric used by structural biologists], revealing detailed features of the nucleotide bases and sugar backbone. I don’t think we could have gotten there without ROCK – or at least not without considerably more resources.” 

Cryo-EM also is able to capture molecules in different states if they, for example, change their 3D conformation as part of their function. Applying ROCK to the Azoarcus intron RNA and the FMN riboswitch, the team managed to identify the different conformations that the Azoarcus intron transitions through during its self-splicing process, and to reveal the relative conformational rigidity of the ligand-binding site of the FMN riboswitch.

“This study by Peng Yin and his collaborators elegantly shows how RNA nanotechnology can work as an accelerator to advance other disciplines. Being able to visualize and understand the structures of many naturally occurring RNA molecules could have tremendous impact on our understanding of many biological and pathological processes across different cell types, tissues, and organisms, and even enable new drug development approaches,” said Wyss Founding Director Donald Ingber, M.D., Ph.D., who is also the Judah Folkman Professor of Vascular Biology at Harvard Medical School and Boston Children’s Hospital, and Professor of Bioengineering at the Harvard John A. Paulson School of Engineering and Applied Sciences.

The study was also authored by Joseph Piccirilli, Ph.D., an expert in RNA chemistry and biochemistry and Professor at The University of Chicago. It was supported by the National Science Foundation (NSF; grant# CMMI-1333215, CCMI-1344915, and CBET-1729397), Air Force Office of Scientific Research (AFOSR; grant MURI FATE, #FA9550-15-1-0514), National Institutes of Health (NIH; grant# 5DP1GM133052, R01GM122797, and R01GM102489), and the Wyss Institute’s Molecular Robotics Initiative.

Here’s a link to and a citation for the paper,

Sub-3-Å cryo-EM structure of RNA enabled by engineered homomeric self-assembly by Di Liu, François A. Thélot, Joseph A. Piccirilli, Maofu Liao & Peng Yin. Nature Methods (2022) DOI: https://doi.org/10.1038/s41592-022-01455-w Published: 02 May 2022

This paper is behind a paywall.

Teaching molecular and synthetic biology in grades K-12

This* story actually started in 2018 with an August 1, 2018 Harvard University news release (h/t Aug. 1, 2018 news item on phys.org) by Leslie Brownell announcing molecular and synthetic biology educational kits that been tested in the classroom. (In 2019, a new kit was released but more about that later.)

As biologists have probed deeper into the molecular and genetic underpinnings of life, K-12 schools have struggled to provide a curriculum that reflects those advances. Hands-on learning is known to be more engaging and effective for teaching science to students, but even the most basic molecular and synthetic biology experiments require equipment far beyond an average classroom’s budget, and often involve the use of bacteria and other substances that can be difficult to manage outside a controlled lab setting.

Now, a collaboration between the Wyss Institute at Harvard University, MIT [Massachusetts Institute of Technology], and Northwestern University has developed BioBits, new educational biology kits that use freeze-dried cell-free (FD-CF) reactions to enable students to perform a range of simple, hands-on biological experiments. The BioBits kits introduce molecular and synthetic biology concepts without the need for specialized lab equipment, at a fraction of the cost of current standard experimental designs. The kits are described in two papers published in Science Advances [2018].

“The main motivation in developing these kits was to give students fun activities that allow them to actually see, smell, and touch the outcomes of the biological reactions they’re doing at the molecular level,” said Ally Huang, a co-first author on both papers who is an MIT graduate student in the lab of Wyss Founding Core Faculty member Jim Collins, Ph.D. “My hope is that they will inspire more kids to consider a career in STEM [science, technology, engineering, and math] and, more generally, give all students a basic understanding of how biology works, because they may one day have to make personal or policy decisions based on modern science.”

Synthetic and molecular biology frequently make use of the cellular machinery found in E. coli bacteria to produce a desired protein. But this system requires that the bacteria be kept alive and contained for an extended period of time, and involves several complicated preparation and processing steps. The FD-CF reactions pioneered in Collins’ lab for molecular manufacturing, when combined with innovations from the lab of Michael Jewett, Ph.D. at Northwestern University, offer a solution to this problem by removing bacteria from the equation altogether.

“You can think of it like opening the hood of a car and taking the engine out: we’ve taken the ‘engine’ that drives protein production out of a bacterial cell and given it the fuel it needs, including ribosomes and amino acids, to create proteins from DNA outside of the bacteria itself,” explained Jewett, who is the Charles Deering McCormick Professor of Teaching Excellence at Northwestern University’s McCormick School of Engineering and co-director of Northwestern’s Center for Synthetic Biology, and co-corresponding author of both papers. This collection of molecular machinery is then freeze-dried into pellets so that it becomes shelf-stable at room temperature. To initiate the transcription of DNA into RNA and the translation of that RNA into a protein, a student just needs to add the desired DNA and water to the freeze-dried pellets.

The researchers designed a range of molecular experiments that can be performed using this system, and coupled each of them to a signal that the students can easily detect with their sense of sight, smell, or touch. The first, called BioBits Bright, contains six different freeze-dried DNA templates that each encode a protein that fluoresces a different color when illuminated with blue light. To produce the proteins, students simply add these DNA templates and water to the FD-CF machinery and put the reactions in an inexpensive incubator (~$30) for several hours, and then view them with a blue light illuminator (~$15). The students can also design their own experiments to produce a desired collection of colors that they can then arrange into a visual image, a bit like using a Light Brite ©. “Challenging the students to build their own in vitro synthetic programs also allows educators to start to talk about how synthetic biologists might control biology to make important products, such as medicines or chemicals,” explained Jessica Stark, an NSF Graduate Research Fellow in the Jewett lab at Northwestern University who is co-first author on both papers.

An expansion of the BioBits Bright kit, called BioBits Explorer, includes experiments that engage the senses of smell and touch and allow students to probe their environment using designer synthetic biosensors. In the first experiment, the FD-CF reaction pellets contain a gene that drives the conversion of isoamyl alcohol to isoamyl acetate, a compound that produces a strong banana odor. In the second experiment, the FD-CF reactions contain a gene coding for the enzyme sortase, which recognizes and links specific segments of proteins in a liquid solution together to form a squishy, semi-solid hydrogel, which the students can touch and manipulate. The third module uses another Wyss technology, the toehold switch sensor, to identify DNA extracted from a banana or a kiwi. The sensors are hairpin-shaped RNA molecules designed such that when they bind to a “trigger” RNA, they spring open and reveal a genetic sequence that produces a fluorescent protein. When fruit DNA is added to the sensor-containing FD-CF pellets, only the sensors that are designed to open in the presence of each fruit’s RNA will produce the fluorescent protein.

The researchers tested their BioBits kits in the Chicago Public School system, and demonstrated that students and teachers were able to perform the experiments in the kits with the same success as trained synthetic biology researchers. In addition to refining the kits’ design so that they can one day provide them to classrooms around the world, the authors hope to create an open-source online database where teachers and students can share their results and ideas for ways to modify the kits to explore different biological questions.

“Synthetic biology is going to be one of the defining technologies of the century, and yet it has been challenging to teach the fundamental concepts of the field in K-12 classrooms given that such efforts often require expensive, complicated equipment,” said Collins, who is a co-corresponding author of both papers and also the Termeer Professor of Medical Engineering & Science at MIT. “We show that it is possible to use freeze-dried, cell-free extracts along with freeze-dried synthetic biology components to conduct innovative educational experiments in classrooms and other low-resource settings. The BioBits kits enable us to expose young kids, older kids, and even adults to the wonders of synthetic biology and, as a result, are poised to transform science education and society.

“All scientists are passionate about what they do, and we are frustrated by the difficulty our educational system has had in inciting a similar level of passion in young people. This BioBits project demonstrates the kind of out-of-the-box thinking and refusal to accept the status quo that we value and cultivate at the Wyss Institute, and we all hope it will stimulate young people to be intrigued by science,” said Wyss Institute Founding Director Donald Ingber, M.D., Ph.D., who is also the Judah Folkman Professor of Vascular Biology at Harvard Medical School (HMS) and the Vascular Biology Program at Boston Children’s Hospital, as well as Professor of Bioengineering at Harvard’s John A. Paulson School of Engineering and Applied Sciences (SEAS). “It’s exciting to see this project move forward and become available to biology classrooms worldwide and, hopefully some of these students will pursue a path in science because of their experience.”

Additional authors of the papers include Peter Nguyen, Ph.D., Nina Donghia, and Tom Ferrante from the Wyss Institute; Melissa Takahashi, Ph.D. and Aaron Dy from MIT; Karen Hsu and Rachel Dubner from Northwestern University; Keith Pardee, Ph.D., Assistant Professor at the University of Toronto; and a number of teachers and students in the Chicago school system including: Mary Anderson, Ada Kanapskyte, Quinn Mucha, Jessica Packett, Palak Patel, Richa Patel, Deema Qaq, Tyler Zondor, Julie Burke, Tom Martinez, Ashlee Miller-Berry, Aparna Puppala, Kara Reichert, Miriam Schmid, Lance Brand, Lander Hill, Jemima Chellaswamy, Nuhie Faheem, Suzanne Fetherling, Elissa Gong, Eddie Marie Gonzales, Teresa Granito, Jenna Koritsaris, Binh Nguyen, Sujud Ottman, Christina Palffy, Angela Patel, Sheila Skweres, Adriane Slaton, and TaRhonda Woods.

This research was supported by the Army Research Office, the National Science Foundation, the Air Force Research Laboratory Center of Excellence Grant, The Defense Threat Reduction Agency Grant, the David and Lucile Packard Foundation, the Camille Dreyfus Teacher-Scholar Program, the Wyss Institute at Harvard University, the Paul G. Allen Frontiers Group, The Air Force Office of Scientific Research, and the Natural Sciences and Engineering Council of Canada. [emphases mine]

Well, that list of funding agencies is quite interesting. The US Army and Air Force but not the Navy? As for what the Natural Sciences and Engineering Council of Canada is doing on that list, I can only imagine why.

This is what they were doing in 2018,

Now for the latest update, a May 7, 2019 news item on phys.org announces the BioBits Kits have been expanded,

How can high school students learn about a technology as complex and abstract as CRISPR? It’s simple: just add water.

A Northwestern University-led team has developed BioBits, a suite of hands-on educational kits that enable students to perform a range of biological experiments by adding water and simple reagents to freeze-dried cell-free reactions. The kits link complex biological concepts to visual, fluorescent readouts, so students know—after a few hours and with a single glance—the results of their experiments.

A May 7, 2019 Northwestern University news release (also on EurekAlert and received via email) by Amanda Morris, which originated the news item, provides more details,

After launching BioBits last summer, the researchers are now expanding the kit to include modules for CRISPR [clustered regularly interspaced short palindromic repeats] and antibiotic resistance. A small group of Chicago-area teachers and high school students just completed the first pilot study for these new modules, which include interactive experiments and supplementary materials exploring ethics and strategies.

“After we unveiled the first kits, we next wanted to tackle current topics that are important for society,” said Northwestern’s Michael Jewett, principal investigator of the study. “That led us to two areas: antibiotic resistance and gene editing.”

Called BioBits Health, the new kits and pilot study are detailed in a paper published today (May 7 [2019]) in the journal ACS Synthetic Biology.

Jewett is a professor of chemical and biological engineering in Northwestern’s McCormick School of Engineering and co-director of Northwestern’s Center for Synthetic Biology. Jessica Stark, a graduate student in Jewett’s laboratory, led the study.

Test in a tube

Instead of using live cells, the BioBits team removed the essential cellular machinery from inside the cells and freeze-dried them for shelf stability. Keeping cells alive and contained for an extended period of time involves several complicated, time-consuming preparation and processing steps as well as expensive equipment. Freeze-dried cell-free reactions bypass those complications and costs.

“These are essentially test-tube biological reactions,” said Stark, a National Science Foundation graduate research fellow. “We break the cells open and use their guts, which still contain all of the necessary biological machinery to carry out a reaction. We no longer need living cells to demonstrate biology.”

This method to harness biological systems without intact, living cells became possible over the last two decades thanks to multiple innovations, including many in cell-free synthetic biology by Jewett’s lab. Not only are these experiments doable in the classroom, they also only cost pennies compared to standard high-tech experimental designs.

“I’m hopeful that students get excited about engineering biology and want to learn more,” Jewett said.

Conquering CRISPR

One of the biggest scientific breakthroughs of the past decade, CRISPR (pronounced “crisper”) stands for Clustered Regularly Interspaced Short Palindromic Repeats. The powerful gene-editing technology uses enzymes to cut DNA in precise locations to turn off or edit targeted genes. It could be used to halt genetic diseases, develop new medicines, make food more nutritious and much more.

BioBits Health uses three components required for CRISPR: an enzyme called the Cas9 protein, a target DNA sequence encoding a fluorescent protein and an RNA molecule that targets the fluorescent protein gene. When students add all three components — and water — to the freeze-dried cell-free system, it creates a reaction that edits, or cuts, the DNA for the fluorescent protein. If the DNA is cut, the system does not glow. If the DNA is not cut, the fluorescent protein is made, and the system glows fluorescent.

“We have linked this abstract, really advanced biological concept to the presence or absence of a fluorescent protein,” Stark said. “It’s something students can see, something they can visually understand.”

The curriculum also includes activities that challenge students to consider the ethical questions and dilemmas surrounding the use of gene-editing technologies.

“There is a lot of excitement about being able to edit genomes with these technologies,” Jewett said. “BioBits Health calls attention to a lot of important questions — not only about how CRISPR technology works but about ethics that society should be thinking about. We hope that this promotes a conversation and dialogue about such technologies.”

Reducing resistance

Jewett and Stark are both troubled by a prediction that, by the year 2050, drug-resistant bacterial infections could outpace cancer as a leading cause of death. This motivated them to help educate the future generation of scientists about how antibiotic resistance emerges and inspire them to take actions that could help limit the emergence of resistant bacteria.
In this module, students run two sets of reactions to produce a glowing fluorescent protein — one set with an antibiotic resistance gene and one set without. Students then add antibiotics. If the experiment glows, the fluorescent protein has been made, and the reaction has become resistant to antibiotics. If the experiment does not glow, then the antibiotic has worked.

“Because we’re using cell-free systems rather than organisms, we can demonstrate drug resistance in a way that doesn’t create drug-resistant bacteria,” Stark explained. “We can demonstrate these concepts without the risks.”

A supporting curriculum piece challenges students to brainstorm and research strategies for slowing the rate of emerging antibiotic resistant strains.

Part of something cool

After BioBits was launched in summer 2018, 330 schools from around the globe requested prototype kits for their science labs. The research team, which includes members from Northwestern and MIT, has received encouraging feedback from teachers, students and parents.

“The students felt like scientists and doctors by touching and using the laboratory materials provided during the demo,” one teacher said. “Even the students who didn’t seem engaged were secretly paying attention and wanted to take their turn pipetting. They knew they were part of something really cool, so we were able to connect with them in a way that was new to them.”

“My favorite part was using the equipment,” a student said. “It was a fun activity that immerses you into what top scientists are currently doing.”

###

The study, “BioBits Health: Classroom activities exploring engineering, biology and human health with fluorescent readouts,” was supported by the Army Research Office (award number W911NF-16-1-0372), the National Science Foundation (grant numbers MCB-1413563 and MCB-1716766), the Air Force Research Laboratory Center of Excellence (grant number FA8650-15-2-5518), the Defense Threat Reduction Agency (grant number HDTRA1-15-10052/P00001), the Department of Energy (grant number DE-SC0018249), the Human Frontiers Science Program (grant number RGP0015/2017), the David and Lucile Packard Foundation, the Office of Energy Efficiency and Renewable Energy (grant number DE-EE008343) and the Camille Dreyfus Teacher-Scholar Program. [emphases mine]

This is an image you’ll find in the abstract for the 2019 paper,

[downloaded from https://pubs.acs.org/doi/10.1021/acssynbio.8b00381]

Here are links and citations for the 2018 papers and the 2019 paper,

BioBits™ Explorer: A modular synthetic biology education kit by Ally Huang, Peter Q. Nguyen, Jessica C. Stark, Melissa K. Takahashi, Nina Donghia, Tom Ferrante, Aaron J. Dy, Karen J. Hsu, Rachel S. Dubner, Keith Pardee, Michael C. Jewett, and James J. Collins. Science Advances 01 Aug 2018: Vol. 4, no. 8, eaat5105 DOI: 10.1126/sciadv.aat5105

BioBits™ Bright: A fluorescent synthetic biology education kit by Jessica C. Stark, Ally Huang, Peter Q. Nguyen, Rachel S. Dubner, Karen J. Hsu, Thomas C. Ferrante, Mary Anderson, Ada Kanapskyte, Quinn Mucha, Jessica S. Packett, Palak Patel, Richa Patel, Deema Qaq, Tyler Zondor, Julie Burke, Thomas Martinez, Ashlee Miller-Berry, Aparna Puppala, Kara Reichert, Miriam Schmid, Lance Brand, Lander R. Hill, Jemima F. Chellaswamy, Nuhie Faheem, Suzanne Fetherling, Elissa Gong, Eddie Marie Gonzalzles, Teresa Granito, Jenna Koritsaris, Binh Nguyen, Sujud Ottman, Christina Palffy, Angela Patel, Sheila Skweres, Adriane Slaton, TaRhonda Woods, Nina Donghia, Keith Pardee, James J. Collins, and Michael C. Jewett. Science Advances 01 Aug 2018: Vol. 4, no. 8, eaat5107 DOI: 10.1126/sciadv.aat5107

BioBits Health: Classroom Activities Exploring Engineering, Biology, and Human Health with Fluorescent Readouts by Jessica C. Stark, Ally Huang, Karen J. Hsu, Rachel S. Dubner, Jason Forbrook, Suzanne Marshalla, Faith Rodriguez, Mechelle Washington, Grant A. Rybnicky, Peter Q. Nguyen, Brenna Hasselbacher, Ramah Jabri, Rijha Kamran, Veronica Koralewski, Will Wightkin, Thomas Martinez, and Michael C. Jewett. ACS Synth. Biol., Article ASAP
DOI: 10.1021/acssynbio.8b00381 Publication Date (Web): March 29, 2019

Copyright © 2019 American Chemical Society

Both of the 2018 papers appear to be open access while the 2019 paper is behind a paywall.

Should you be interested in acquiring a BioBits kit, you can check out the BioBits website. As for ‘conguering’ CRISPR, do we really need to look at it that way? Maybe a more humble appraoch could work just as well or even better, eh?

*’is’ removed from sentence on May 9, 2019.

A 3D printed eye cornea and a 3D printed copy of your brain (also: a Brad Pitt connection)

Sometimes it’s hard to keep up with 3D tissue printing news. I have two news bits, one concerning eyes and another concerning brains.

3D printed human corneas

A May 29, 2018 news item on ScienceDaily trumpets the news,

The first human corneas have been 3D printed by scientists at Newcastle University, UK.

It means the technique could be used in the future to ensure an unlimited supply of corneas.

As the outermost layer of the human eye, the cornea has an important role in focusing vision.

Yet there is a significant shortage of corneas available to transplant, with 10 million people worldwide requiring surgery to prevent corneal blindness as a result of diseases such as trachoma, an infectious eye disorder.

In addition, almost 5 million people suffer total blindness due to corneal scarring caused by burns, lacerations, abrasion or disease.

The proof-of-concept research, published today [May 29, 2018] in Experimental Eye Research, reports how stem cells (human corneal stromal cells) from a healthy donor cornea were mixed together with alginate and collagen to create a solution that could be printed, a ‘bio-ink’.

Here are the proud researchers with their cornea,

Caption: Dr. Steve Swioklo and Professor Che Connon with a dyed cornea. Credit: Newcastle University, UK

A May 30,2018 Newcastle University press release (also on EurekAlert but published on May 29, 2018), which originated the news item, adds more details,

Using a simple low-cost 3D bio-printer, the bio-ink was successfully extruded in concentric circles to form the shape of a human cornea. It took less than 10 minutes to print.

The stem cells were then shown to culture – or grow.

Che Connon, Professor of Tissue Engineering at Newcastle University, who led the work, said: “Many teams across the world have been chasing the ideal bio-ink to make this process feasible.

“Our unique gel – a combination of alginate and collagen – keeps the stem cells alive whilst producing a material which is stiff enough to hold its shape but soft enough to be squeezed out the nozzle of a 3D printer.

“This builds upon our previous work in which we kept cells alive for weeks at room temperature within a similar hydrogel. Now we have a ready to use bio-ink containing stem cells allowing users to start printing tissues without having to worry about growing the cells separately.”

The scientists, including first author and PhD student Ms Abigail Isaacson from the Institute of Genetic Medicine, Newcastle University, also demonstrated that they could build a cornea to match a patient’s unique specifications.

The dimensions of the printed tissue were originally taken from an actual cornea. By scanning a patient’s eye, they could use the data to rapidly print a cornea which matched the size and shape.

Professor Connon added: “Our 3D printed corneas will now have to undergo further testing and it will be several years before we could be in the position where we are using them for transplants.

“However, what we have shown is that it is feasible to print corneas using coordinates taken from a patient eye and that this approach has potential to combat the world-wide shortage.”

Here’s a link to and a citation for the paper,

3D bioprinting of a corneal stroma equivalent by Abigail Isaacson, Stephen Swioklo, Che J. Connon. Experimental Eye Research Volume 173, August 2018, Pages 188–193 and 2018 May 14 pii: S0014-4835(18)30212-4. doi: 10.1016/j.exer.2018.05.010. [Epub ahead of print]

This paper is behind a paywall.

A 3D printed copy of your brain

I love the title for this May 30, 2018 Wyss Institute for Biologically Inspired Engineering news release: Creating piece of mind by Lindsay Brownell (also on EurekAlert),

What if you could hold a physical model of your own brain in your hands, accurate down to its every unique fold? That’s just a normal part of life for Steven Keating, Ph.D., who had a baseball-sized tumor removed from his brain at age 26 while he was a graduate student in the MIT Media Lab’s Mediated Matter group. Curious to see what his brain actually looked like before the tumor was removed, and with the goal of better understanding his diagnosis and treatment options, Keating collected his medical data and began 3D printing his MRI [magnetic resonance imaging] and CT [computed tomography] scans, but was frustrated that existing methods were prohibitively time-intensive, cumbersome, and failed to accurately reveal important features of interest. Keating reached out to some of his group’s collaborators, including members of the Wyss Institute at Harvard University, who were exploring a new method for 3D printing biological samples.

“It never occurred to us to use this approach for human anatomy until Steve came to us and said, ‘Guys, here’s my data, what can we do?” says Ahmed Hosny, who was a Research Fellow with at the Wyss Institute at the time and is now a machine learning engineer at the Dana-Farber Cancer Institute. The result of that impromptu collaboration – which grew to involve James Weaver, Ph.D., Senior Research Scientist at the Wyss Institute; Neri Oxman, [emphasis mine] Ph.D., Director of the MIT Media Lab’s Mediated Matter group and Associate Professor of Media Arts and Sciences; and a team of researchers and physicians at several other academic and medical centers in the US and Germany – is a new technique that allows images from MRI, CT, and other medical scans to be easily and quickly converted into physical models with unprecedented detail. The research is reported in 3D Printing and Additive Manufacturing.

“I nearly jumped out of my chair when I saw what this technology is able to do,” says Beth Ripley, M.D. Ph.D., an Assistant Professor of Radiology at the University of Washington and clinical radiologist at the Seattle VA, and co-author of the paper. “It creates exquisitely detailed 3D-printed medical models with a fraction of the manual labor currently required, making 3D printing more accessible to the medical field as a tool for research and diagnosis.”

Imaging technologies like MRI and CT scans produce high-resolution images as a series of “slices” that reveal the details of structures inside the human body, making them an invaluable resource for evaluating and diagnosing medical conditions. Most 3D printers build physical models in a layer-by-layer process, so feeding them layers of medical images to create a solid structure is an obvious synergy between the two technologies.

However, there is a problem: MRI and CT scans produce images with so much detail that the object(s) of interest need to be isolated from surrounding tissue and converted into surface meshes in order to be printed. This is achieved via either a very time-intensive process called “segmentation” where a radiologist manually traces the desired object on every single image slice (sometimes hundreds of images for a single sample), or an automatic “thresholding” process in which a computer program quickly converts areas that contain grayscale pixels into either solid black or solid white pixels, based on a shade of gray that is chosen to be the threshold between black and white. However, medical imaging data sets often contain objects that are irregularly shaped and lack clear, well-defined borders; as a result, auto-thresholding (or even manual segmentation) often over- or under-exaggerates the size of a feature of interest and washes out critical detail.

The new method described by the paper’s authors gives medical professionals the best of both worlds, offering a fast and highly accurate method for converting complex images into a format that can be easily 3D printed. The key lies in printing with dithered bitmaps, a digital file format in which each pixel of a grayscale image is converted into a series of black and white pixels, and the density of the black pixels is what defines the different shades of gray rather than the pixels themselves varying in color.

Similar to the way images in black-and-white newsprint use varying sizes of black ink dots to convey shading, the more black pixels that are present in a given area, the darker it appears. By simplifying all pixels from various shades of gray into a mixture of black or white pixels, dithered bitmaps allow a 3D printer to print complex medical images using two different materials that preserve all the subtle variations of the original data with much greater accuracy and speed.

The team of researchers used bitmap-based 3D printing to create models of Keating’s brain and tumor that faithfully preserved all of the gradations of detail present in the raw MRI data down to a resolution that is on par with what the human eye can distinguish from about 9-10 inches away. Using this same approach, they were also able to print a variable stiffness model of a human heart valve using different materials for the valve tissue versus the mineral plaques that had formed within the valve, resulting in a model that exhibited mechanical property gradients and provided new insights into the actual effects of the plaques on valve function.

“Our approach not only allows for high levels of detail to be preserved and printed into medical models, but it also saves a tremendous amount of time and money,” says Weaver, who is the corresponding author of the paper. “Manually segmenting a CT scan of a healthy human foot, with all its internal bone structure, bone marrow, tendons, muscles, soft tissue, and skin, for example, can take more than 30 hours, even by a trained professional – we were able to do it in less than an hour.”

The researchers hope that their method will help make 3D printing a more viable tool for routine exams and diagnoses, patient education, and understanding the human body. “Right now, it’s just too expensive for hospitals to employ a team of specialists to go in and hand-segment image data sets for 3D printing, except in extremely high-risk or high-profile cases. We’re hoping to change that,” says Hosny.

In order for that to happen, some entrenched elements of the medical field need to change as well. Most patients’ data are compressed to save space on hospital servers, so it’s often difficult to get the raw MRI or CT scan files needed for high-resolution 3D printing. Additionally, the team’s research was facilitated through a joint collaboration with leading 3D printer manufacturer Stratasys, which allowed access to their 3D printer’s intrinsic bitmap printing capabilities. New software packages also still need to be developed to better leverage these capabilities and make them more accessible to medical professionals.

Despite these hurdles, the researchers are confident that their achievements present a significant value to the medical community. “I imagine that sometime within the next 5 years, the day could come when any patient that goes into a doctor’s office for a routine or non-routine CT or MRI scan will be able to get a 3D-printed model of their patient-specific data within a few days,” says Weaver.

Keating, who has become a passionate advocate of efforts to enable patients to access their own medical data, still 3D prints his MRI scans to see how his skull is healing post-surgery and check on his brain to make sure his tumor isn’t coming back. “The ability to understand what’s happening inside of you, to actually hold it in your hands and see the effects of treatment, is incredibly empowering,” he says.

“Curiosity is one of the biggest drivers of innovation and change for the greater good, especially when it involves exploring questions across disciplines and institutions. The Wyss Institute is proud to be a space where this kind of cross-field innovation can flourish,” says Wyss Institute Founding Director Donald Ingber, M.D., Ph.D., who is also the Judah Folkman Professor of Vascular Biology at Harvard Medical School (HMS) and the Vascular Biology Program at Boston Children’s Hospital, as well as Professor of Bioengineering at Harvard’s John A. Paulson School of Engineering and Applied Sciences (SEAS).

Here’s an image illustrating the work,

Caption: This 3D-printed model of Steven Keating’s skull and brain clearly shows his brain tumor and other fine details thanks to the new data processing method pioneered by the study’s authors. Credit: Wyss Institute at Harvard University

Here’s a link to and a citation for the paper,

From Improved Diagnostics to Presurgical Planning: High-Resolution Functionally Graded Multimaterial 3D Printing of Biomedical Tomographic Data Sets by Ahmed Hosny , Steven J. Keating, Joshua D. Dilley, Beth Ripley, Tatiana Kelil, Steve Pieper, Dominik Kolb, Christoph Bader, Anne-Marie Pobloth, Molly Griffin, Reza Nezafat, Georg Duda, Ennio A. Chiocca, James R.. Stone, James S. Michaelson, Mason N. Dean, Neri Oxman, and James C. Weaver. 3D Printing and Additive Manufacturing http://doi.org/10.1089/3dp.2017.0140 Online Ahead of Print:May 29, 2018

This paper appears to be open access.

A tangential Brad Pitt connection

It’s a bit of Hollywood gossip. There was some speculation in April 2018 that Brad Pitt was dating Dr. Neri Oxman highlighted in the Wyss Institute news release. Here’s a sample of an April 13, 2018 posting on Laineygossip (Note: A link has been removed),

It took him a long time to date, but he is now,” the insider tells PEOPLE. “He likes women who challenge him in every way, especially in the intellect department. Brad has seen how happy and different Amal has made his friend (George Clooney). It has given him something to think about.”

While a Pitt source has maintained he and Oxman are “just friends,” they’ve met up a few times since the fall and the insider notes Pitt has been flying frequently to the East Coast. He dropped by one of Oxman’s classes last fall and was spotted at MIT again a few weeks ago.

Pitt and Oxman got to know each other through an architecture project at MIT, where she works as a professor of media arts and sciences at the school’s Media Lab. Pitt has always been interested in architecture and founded the Make It Right Foundation, which builds affordable and environmentally friendly homes in New Orleans for people in need.

“One of the things Brad has said all along is that he wants to do more architecture and design work,” another source says. “He loves this, has found the furniture design and New Orleans developing work fulfilling, and knows he has a talent for it.”

It’s only been a week since Page Six first broke the news that Brad and Dr Oxman have been spending time together.

I’m fascinated by Oxman’s (and her colleagues’) furniture. Rose Brook writes about one particular Oxman piece in her March 27, 2014 posting for TCT magazine (Note: Links have been removed),

MIT Professor and 3D printing forerunner Neri Oxman has unveiled her striking acoustic chaise longue, which was made using Stratasys 3D printing technology.

Oxman collaborated with Professor W Craig Carter and Composer and fellow MIT Professor Tod Machover to explore material properties and their spatial arrangement to form the acoustic piece.

Christened Gemini, the two-part chaise was produced using a Stratasys Objet500 Connex3 multi-colour, multi-material 3D printer as well as traditional furniture-making techniques and it will be on display at the Vocal Vibrations exhibition at Le Laboratoire in Paris from March 28th 2014.

An Architect, Designer and Professor of Media, Arts and Science at MIT, Oxman’s creation aims to convey the relationship of twins in the womb through material properties and their arrangement. It was made using both subtractive and additive manufacturing and is part of Oxman’s ongoing exploration of what Stratasys’ ground-breaking multi-colour, multi-material 3D printer can do.

Brook goes on to explain how the chaise was made and the inspiration that led to it. Finally, it’s interesting to note that Oxman was working with Stratasys in 2014 and that this 2018 brain project is being developed in a joint collaboration with Statasys.

That’s it for 3D printing today.

A nano fabrication technique used to create next generation heart valve

I am going to have take the researchers’ word that these somehow lead to healthy heart valve tissue,

In rotary jet spinning technology, a rotating nozzle extrudes a solution of extracellular matrix (ECM) into nanofibers that wrap themselves around heart valve-shaped mandrels. By using a series of mandrels with different sizes, the manufacturing process becomes fully scalable and is able to provide JetValves for all age groups and heart sizes. Credit: Wyss Institute at Harvard University

From a May 18, 2017 news item on ScienceDaily,

The human heart beats approximately 35 million times every year, effectively pumping blood into the circulation via four different heart valves. Unfortunately, in over four million people each year, these delicate tissues malfunction due to birth defects, age-related deteriorations, and infections, causing cardiac valve disease.

Today, clinicians use either artificial prostheses or fixed animal and cadaver-sourced tissues to replace defective valves. While these prostheses can restore the function of the heart for a while, they are associated with adverse comorbidity and wear down and need to be replaced during invasive and expensive surgeries. Moreover, in children, implanted heart valve prostheses need to be replaced even more often as they cannot grow with the child.

A team lead by Kevin Kit Parker, Ph.D. at Harvard University’s Wyss Institute for Biologically Inspired Engineering recently developed a nanofiber fabrication technique to rapidly manufacture heart valves with regenerative and growth potential. In a paper published in Biomaterials, Andrew Capulli, Ph.D. and colleagues fabricated a valve-shaped nanofiber network that mimics the mechanical and chemical properties of the native valve extracellular matrix (ECM). To achieve this, the team used the Parker lab’s proprietary rotary jet spinning technology — in which a rotating nozzle extrudes an ECM solution into nanofibers that wrap themselves around heart valve-shaped mandrels. “Our setup is like a very fast cotton candy machine that can spin a range of synthetic and natural occurring materials. In this study, we used a combination of synthetic polymers and ECM proteins to fabricate biocompatible JetValves that are hemodynamically competent upon implantation and support cell migration and re-population in vitro. Importantly, we can make human-sized JetValves in minutes — much faster than possible for other regenerative prostheses,” said Parker.

A May 18,2017 Wyss Institute for Biologically Inspired Engineering news release (also on EurekAlert), which originated the news item, expands on the theme of Jetvalves,

To further develop and test the clinical potential of JetValves, Parker’s team collaborated with the translational team of Simon P. Hoerstrup, M.D., Ph.D., at the University of Zurich in Switzerland, which is a partner institution with the Wyss Institute. As a leader in regenerative heart prostheses, Hoerstrup and his team in Zurich have previously developed regenerative, tissue-engineered heart valves to replace mechanical and fixed-tissue heart valves. In Hoerstrup’s approach, human cells directly deposit a regenerative layer of complex ECM on biodegradable scaffolds shaped as heart valves and vessels. The living cells are then eliminated from the scaffolds resulting in an “off-the-shelf” human matrix-based prostheses ready for implantation.

In the paper, the cross-disciplinary team successfully implanted JetValves in sheep using a minimally invasive technique and demonstrated that the valves functioned properly in the circulation and regenerated new tissue. “In our previous studies, the cell-derived ECM-coated scaffolds could recruit cells from the receiving animal’s heart and support cell proliferation, matrix remodeling, tissue regeneration, and even animal growth. While these valves are safe and effective, their manufacturing remains complex and expensive as human cells must be cultured for a long time under heavily regulated conditions. The JetValve’s much faster manufacturing process can be a game-changer in this respect. If we can replicate these results in humans, this technology could have invaluable benefits in minimizing the number of pediatric re-operations,” said Hoerstrup.

In support of these translational efforts, the Wyss Institute for Biologically Inspired Engineering and the University of Zurich announced today a cross-institutional team effort to generate a functional heart valve replacement with the capacity for repair, regeneration, and growth. The team is also working towards a GMP-grade version of their customizable, scalable, and cost-effective manufacturing process that would enable deployment to a large patient population. In addition, the new heart valve would be compatible with minimally invasive procedures to serve both pediatric and adult patients.

The project will be led jointly by Parker and Hoerstrup. Parker is a Core Faculty member of the Wyss Institute and the Tarr Family Professor of Bioengineering and Applied Physics at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS). Hoerstrup is Chair and Director of the University of Zurich’s Institute for Regenerative Medicine (IREM), Co-Director of the recently founded Wyss Translational Center Zurich and a Wyss Institute Associate Faculty member.

Since JetValves can be manufactured in all desired shapes and sizes, and take seconds to minutes to produce, the team’s goal is to provide customized, ready-to-use, regenerative heart valves much faster and at much lower cost than currently possible.

“Achieving the goal of minimally invasive, low-cost regenerating heart valves could have tremendous impact on patients’ lives across age-, social- and geographical boundaries. Once again, our collaborative team structure that combines unique and leading expertise in bioengineering, regenerative medicine, surgical innovation and business development across the Wyss Institute and our partner institutions, makes it possible for us to advance technology development in ways not possible in a conventional academic laboratory,” said Wyss Institute Founding Director Donald Ingber, M.D., Ph.D., who is also the Judah Folkman Professor of Vascular Biology at HMS and the Vascular Biology Program at Boston Children’s Hospital, as well as Professor of Bioengineering at SEAS.

This scanning electron microscopy image shows how extracellular matrix (ECM) nanofibers generated with JetValve technology are arranged in parallel networks with physical properties comparable to those found in native heart tissue. Credit: Wyss Institute at Harvard University

Here’s a link to and a citation for the paper,

JetValve: Rapid manufacturing of biohybrid scaffolds for biomimetic heart valve replacement by Andrew K. Capulli, Maximillian Y. Emmert, Francesco S. Pasqualini, b, Debora Kehl, Etem Caliskan, Johan U. Lind, Sean P. Sheehy, Sung Jin Park, Seungkuk Ahn, Benedikt Webe, Josue A. Goss. Biomaterials Volume 133, July 2017, Pages 229–241  https://doi.org/10.1016/j.biomaterials.2017.04.033

This paper is behind a paywall.

4D printing: a hydrogel orchid

In 2013, the 4th dimension for printing was self-assembly according to a March 1, 2013 article by Tuan Nguyen for ZDNET. A Jan. 25, 2016 Wyss Institute for Biologically Inspired Engineering at Harvard University news release (also on EurekAlert) points to time as the fourth dimension in a description of the Wyss Institute’s latest 4D printed object,

A team of scientists at the Wyss Institute for Biologically Inspired Engineering at Harvard University and the Harvard John A. Paulson School of Engineering and Applied Sciences has evolved their microscale 3D printing technology to the fourth dimension, time. Inspired by natural structures like plants, which respond and change their form over time according to environmental stimuli, the team has unveiled 4D-printed hydrogel composite structures that change shape upon immersion in water.

“This work represents an elegant advance in programmable materials assembly, made possible by a multidisciplinary approach,” said Jennifer Lewis, Sc.D., senior author on the new study. “We have now gone beyond integrating form and function to create transformable architectures.”

In nature, flowers and plants have tissue composition and microstructures that result in dynamic morphologies that change according to their environments. Mimicking the variety of shape changes undergone by plant organs such as tendrils, leaves, and flowers in response to environmental stimuli like humidity and/or temperature, the 4D-printed hydrogel composites developed by Lewis and her team are programmed to contain precise, localized swelling behaviors. Importantly, the hydrogel composites contain cellulose fibrils that are derived from wood and are similar to the microstructures that enable shape changes in plants.

By aligning cellulose fibrils (also known as, cellulose nanofibrils or nanofibrillated cellulose) during printing, the hydrogel composite ink is encoded with anisotropic swelling and stiffness, which can be patterned to produce intricate shape changes. The anisotropic nature of the cellulose fibrils gives rise to varied directional properties that can be predicted and controlled. Just like wood, which can be split easier along the grain rather than across it. Likewise, when immersed in water, the hydrogel-cellulose fibril ink undergoes differential swelling behavior along and orthogonal to the printing path. Combined with a proprietary mathematical model developed by the team that predicts how a 4D object must be printed to achieve prescribed transformable shapes, the new method opens up many new and exciting potential applications for 4D printing technology including smart textiles, soft electronics, biomedical devices, and tissue engineering.

“Using one composite ink printed in a single step, we can achieve shape-changing hydrogel geometries containing more complexity than any other technique, and we can do so simply by modifying the print path,” said Gladman [A. Sydney Gladman, Wyss Institute a graduate research assistant]. “What’s more, we can interchange different materials to tune for properties such as conductivity or biocompatibility.”

The composite ink that the team uses flows like liquid through the printhead, yet rapidly solidifies once printed. A variety of hydrogel materials can be used interchangeably resulting in different stimuli-responsive behavior, while the cellulose fibrils can be replaced with other anisotropic fillers of choice, including conductive fillers.

“Our mathematical model prescribes the printing pathways required to achieve the desired shape-transforming response,” said Matsumoto [Elisabetta Matsumoto, Ph.D., a postdoctoral fellow at the Wyss]. “We can control the curvature both discretely and continuously using our entirely tunable and programmable method.”

Specifically, the mathematical modeling solves the “inverse problem”, which is the challenge of being able to predict what the printing toolpath must be in order to encode swelling behaviors toward achieving a specific desired target shape.

“It is wonderful to be able to design and realize, in an engineered structure, some of nature’s solutions,” said Mahadevan [L. Mahadevan, Ph.D., a Wyss Core Faculty member] , who has studied phenomena such as how botanical tendrils coil, how flowers bloom, and how pine cones open and close. “By solving the inverse problem, we are now able to reverse-engineer the problem and determine how to vary local inhomogeneity, i.e. the spacing between the printed ink filaments, and the anisotropy, i.e. the direction of these filaments, to control the spatiotemporal response of these shapeshifting sheets. ”

“What’s remarkable about this 4D printing advance made by Jennifer and her team is that it enables the design of almost any arbitrary, transformable shape from a wide range of available materials with different properties and potential applications, truly establishing a new platform for printing self-assembling, dynamic microscale structures that could be applied to a broad range of industrial and medical applications,” said Wyss Institute Founding Director Donald Ingber, M.D., Ph.D., who is also the Judah Folkman Professor of Vascular Biology at Harvard Medical School and the Vascular Biology Program at Boston Children’s Hospital and Professor of Bioengineering at Harvard SEAS [School of Engineering and Applied Science’.

Here’s an animation from the Wyss Institute illustrating the process,

And, here’s a link to and a citation for the paper,

Biomimetic 4D printing by A. Sydney Gladman, Elisabetta A. Matsumoto, Ralph G. Nuzzo, L. Mahadevan, & Jennifer A. Lewis. Nature Materials (2016) doi:10.1038/nmat4544 Published online 25 January 2016

This paper is behind a paywall.

Organ chips for DARPA (Defense Advanced Research Projects Agency)

The Wyss Institute will receive up to  $37M US for a project that integrates ten different organ-on-a-chip projects into one system. From the July 24, 2012 news release on EurekAlert,

With this new DARPA funding, Institute researchers and a multidisciplinary team of collaborators seek to build 10 different human organs-on-chips, to link them together to more closely mimic whole body physiology, and to engineer an automated instrument that will control fluid flow and cell viability while permitting real-time analysis of complex biochemical functions. As an accurate alternative to traditional animal testing models that often fail to predict human responses, this instrumented “human-on-a-chip” will be used to rapidly assess responses to new drug candidates, providing critical information on their safety and efficacy.

This unique platform could help ensure that safe and effective therapeutics are identified sooner, and ineffective or toxic ones are rejected early in the development process. As a result, the quality and quantity of new drugs moving successfully through the pipeline and into the clinic may be increased, regulatory decision-making could be better informed, and patient outcomes could be improved.

Jesse Goodman, FDA Chief Scientist and Deputy Commissioner for Science and Public Health, commented that the automated human-on-chip instrument being developed “has the potential to be a better model for determining human adverse responses. FDA looks forward to working with the Wyss Institute in its development of this model that may ultimately be used in therapeutic development.”

Wyss Founding Director, Donald Ingber, M.D., Ph.D., and Wyss Core Faculty member, Kevin Kit Parker, Ph.D., will co-lead this five-year project.

I note that Kevin Kit Parker was mentioned in an earlier posting today (July 26, 2012) titled, Medusa, jellyfish, and tissue engineering, and Donald Ingber in my Dec.1e, 2011 posting about Shrilk and insect skeletons.

As for the Wyss Institute, here’s a description from the news release,

The Wyss Institute for Biologically Inspired Engineering at Harvard University (http://wyss.harvard.edu) uses Nature’s design principles to develop bioinspired materials and devices that will transform medicine and create a more sustainable world. Working as an alliance among Harvard’s Schools of Medicine, Engineering, and Arts & Sciences, and in partnership with Beth Israel Deaconess Medical Center, Boston Children’s Hospital, Brigham and Women’s Hospital, , Dana Farber Cancer Institute, Massachusetts General Hospital, the University of Massachusetts Medical School, Spaulding Rehabilitation Hospital, Tufts University, and Boston University, the Institute crosses disciplinary and institutional barriers to engage in high-risk research that leads to transformative technological breakthroughs. By emulating Nature’s principles for self-organizing and self-regulating, Wyss researchers are developing innovative new engineering solutions for healthcare, energy, architecture, robotics, and manufacturing. These technologies are translated into commercial products and therapies through collaborations with clinical investigators, corporate alliances, and new start-ups.

I hadn’t thought of an organ-on-a-chip as particularly bioinspired so I’ll have to think about that one for a while.

Shrilk—save your insect skeletons, they may come in handy

If you should happen to find a dead beetle or other insect with a hard exoskeleton, take a good look and marvel at strength that doesn’t require bulk or weight. Scientists at the Wyss Institute for Biologically Inspired Engineering at Harvard University have been inspired by those exoskeletons, made of  something called insect cuticle, to create a new material, shrilk. From the Dec. 13, 2011 news item on phosorg.com,

Researchers at the Wyss Institute for Biologically Inspired Engineering at Harvard University have developed a new material that replicates the exceptional strength, toughness, and versatility of one of nature’s more extraordinary substances—insect cuticle. Also low-cost, biodegradable, and biocompatible, the new material, called “Shrilk,” could one day replace plastics in consumer products and be used safely in a variety of medical applications.

Natural insect cuticle, such as that found in the rigid exoskeleton of a housefly or grasshopper, is uniquely suited to the challenge of providing protection without adding weight or bulk. As such, it can deflect external chemical and physical strains without damaging the insect’s internal components, while providing structure for the insect’s muscles and wings. It is so light that it doesn’t inhibit flight and so thin that it allows flexibility. Also remarkable is its ability to vary its properties, from rigid along the insect’s body segments and wings to elastic along its limb joints.

Insect cuticle is a composite material consisting of layers of chitin, a polysaccharide polymer, and protein organized in a laminar, plywood-like structure. Mechanical and chemical interactions between these materials provide the cuticle with its unique mechanical and chemical properties. By studying these complex interactions and recreating this unique chemistry and laminar design in the lab, Fernandez [Javier G. Fernandez] and Ingber [Donald Ingber] were able to engineer a thin, clear film that has the same composition and structure as insect cuticle. The material is called Shrilk because it is composed of fibroin protein from silk and from chitin, which is commonly extracted from discarded shrimp shells. [emphasis mine]

The researchers say that shrilk could be used as an environmentally-safe and biodegradable alternative to plastic, e.g. trash bags, diapers, and packaging. It could also be used to suture wounds.