Tag Archives: in silico testing

Lungs: EU SmartNanoTox and Pneumo NP

I have three news bits about lungs one concerning relatively new techniques for testing the impact nanomaterials may have on lungs and two concerning developments at PneumoNP; the first regarding a new technique for getting antibiotics to a lung infected with pneumonia and the second, a new antibiotic.

Predicting nanotoxicity in the lungs

From a June 13, 2016 news item on Nanowerk,

Scientists at the Helmholtz Zentrum München [German Research Centre for Environmental Health] have received more than one million euros in the framework of the European Horizon 2020 Initiative [a major European Commission science funding initiative successor to the Framework Programme 7 initiative]. Dr. Tobias Stöger and Dr. Otmar Schmid from the Institute of Lung Biology and Disease and the Comprehensive Pneumology Center (CPC) will be using the funds to develop new tests to assess risks posed by nanomaterials in the airways. This could contribute to reducing the need for complex toxicity tests.

A June 13, 2016 Helmholtz Zentrum München (German Research Centre for Environmental Health) press release, which originated the news item, expands on the theme,

Nanoparticles are extremely small particles that can penetrate into remote parts of the body. While researchers are investigating various strategies for harvesting the potential of nanoparticles for medical applications, they could also pose inherent health risks*. Currently the hazard assessment of nanomaterials necessitates a complex and laborious procedure. In addition to complete material characterization, controlled exposure studies are needed for each nanomaterial in order to guarantee the toxicological safety.

As a part of the EU SmartNanoTox project, which has now been funded with a total of eight million euros, eleven European research partners, including the Helmholtz Zentrum München, want to develop a new concept for the toxicological assessment of nanomaterials.

Reference database for hazardous substances

Biologist Tobias Stöger and physicist Otmar Schmid, both research group heads at the Institute of Lung Biology and Disease, hope that the use of modern methods will help to advance the assessment procedure. “We hope to make more reliable nanotoxicity predictions by using modern approaches involving systems biology, computer modelling, and appropriate statistical methods,” states Stöger.

The lung experts are concentrating primarily on the respiratory tract. The approach involves defining a representative selection of toxic nanomaterials and conducting an in-depth examination of their structure and the various molecular modes of action that lead to their toxicity. These data are then digitalized and transferred to a reference database for new nanomaterials. Economical tests that are easy to conduct should then make it possible to assess the toxicological potential of these new nanomaterials by comparing the test results s with what is already known from the database. “This should make it possible to predict whether or not a newly developed nanomaterial poses a health risk,” Otmar Schmid says.

* Review: Schmid, O. and Stoeger, T. (2016). Surface area is the biologically most effective dose metric for acute nanoparticle toxicity in the lung. Journal of Aerosol Science, DOI:10.1016/j.jaerosci.2015.12.006

The SmartNanoTox webpage is here on the European Commission’s Cordis website.

Carrying antibiotics into lungs (PneumoNP)

I received this news from the European Commission’s PneumoNP project (I wrote about PneumoNP in a June 26, 2014 posting when it was first announced). This latest development is from a March 21, 2016 email (the original can be found here on the How to pack antibiotics in nanocarriers webpage on the PneumoNP website),

PneumoNP researchers work on a complex task: attach or encapsulate antibiotics with nanocarriers that are stable enough to be included in an aerosol formulation, to pass through respiratory tracts and finally deliver antibiotics on areas of lungs affected by pneumonia infections. The good news is that they finally identify two promising methods to generate nanocarriers.

So far, compacting polymer coils into single-chain nanoparticles in water and mild conditions was an unsolved issue. But in Spain, IK4-CIDETEC scientists developed a covalent-based method that produces nanocarriers with remarkable stability under those particular conditions. Cherry on the cake, the preparation is scalable for more industrial production. IK4-CIDETEC patented the process.

Fig.: A polymer coil (step 1) compacts into a nanocarrier with cross-linkers (step 2). Then, antibiotics get attached to the nanocarrier (step 3).

At the same time, another route to produce lipidic nanocarriers have been developed by researchers from Utrecht University. In particular, they optimized the method consisting in assembling lipids directly around a drug. As a result, generated lipidic nanocarriers show encouraging stability properties and are able to carry sufficient quantity of antibiotics.

Fig.: On presence of antibiotics, a lipidic layer (step 1) aggregates the drug (step 2) until the lipids forms a capsule around antibiotics (step 3).

Assays of both polymeric and lipidic nanocarriers are currently performed by ITEM Fraunhofer Institute in Germany, Ingeniatrics Tecnologias in Spain and Erasmus Medical Centre in the Netherlands. Part of these tests allows to make sure that the nanocarriers are not toxic to cells. Other tests are also done to verify that the efficiency of antibiotics on Klebsiella Pneumoniae bacteria when they are attached to nanocarriers.

A new antibiotic for pneumonia (PneumoNP)

A June 14, 2016 PneumoNP press release (received via email) announces work on a promising new approach to an antibiotic for pneumonia,

The antimicrobial peptide M33 may be the long-sought substitute to treat difficult lung infections, like multi-drug resistant pneumonia.

In 2013, the European Respiratory Society predicted 3 millions cases of pneumonia in Europe every year [1]. The standard treatment for pneumonia is an intravenous administration of a combination of drugs. This leads to the development of antibiotic resistance in the population. Gradually, doctors are running out of solutions to cure patients. An Italian company suggests a new option: the M33 peptide.

Few years ago, the Italian company SetLance SRL decided to investigate the M33 peptide. The antimicrobial peptide is an optimized version of an artificial peptide sequence selected for its efficacy and stability. So far, it showed encouraging in-vitro results against multidrug-resistant Gram-negative bacteria, including Klebsiella Pneumoniae. With the support of EU funding to the PneumoNP project, SetLance SRL had the opportunity to develop a new formulation of M33 that enhances its antimicrobial activity.

The new formulation of M33 fights Gram-negative bacteria in three steps. First of all, the M33 binds with the lipopolysaccharides (LPS) on the outer membrane of bacteria. Then, the molecule forms a helix and finally disrupts the membrane provoking cytoplasm leaking. The peptide enabled up to 80% of mices to survive Pseudomonas Aeruginosa-based lung infections. Beyond these encouraging results, toxicity to the new M33 formulation seems to be much lower than antimicrobial peptides currently used in clinical practice like colistin [2].

Lately, SetLance scaled-up the synthesis route and is now able to produce several hundred milligrams per batch. The molecule is robust enough for industrial production. We may expect this drug to go on clinical development and validation at the beginning of 2018.

[1] http://www.erswhitebook.org/chapters/acute-lower-respiratory-infections/pneumonia/
[2] Ceccherini et al., Antimicrobial activity of levofloxacin-M33 peptide conjugation or combination, Chem Med Comm. 2016; Brunetti et al., In vitro and in vivo efficacy, toxicity, bio-distribution and resistance selection of a novel antibacterial drug candidate. Scientific Reports 2016

I believe all the references are open access.

Brief final comment

The only element linking these news bits together is that they concern the lungs.

A pragmatic approach to alternatives to animal testing

Maryse de la Giroday explains how emerging innovations can provide much-needed alternatives to animal testing. She also shares highlights of the 9^th World Congress on Alternatives to Animal Testing.

‘Guinea pigging’ is the practice of testing drugs that have passed in vitro and in vivo tests on healthy humans in a Phase I clinical trial. In fact, healthy humans can make quite a bit of money as guinea pigs. The practice is sufficiently well-entrenched that there is a magazine, Guinea Pig Zero, devoted to professionals. While most participants anticipate some unpleasant side effects, guinea pigging can sometimes be a dangerous ‘profession’.

HARMFUL TO HEALTH

One infamous incident highlighting the dangers of guinea pigging occurred in 2006 at Northwick Park Hospital outside London. Volunteers were offered £2,000 to participate in a Phase I clinical trial to test a prospective treatment – a monoclonal antibody designed for rheumatoid arthritis and multiple sclerosis. The drug, called TGN1412, caused catastrophic systemic organ failure in participants. All six individuals receiving the drug required hospital treatment. One participant reportedly underwent amputation of fingers and toes. Another reacted with symptoms comparable to John Merrick, the Elephant Man.

The root of the disaster lay in subtle immune system differences between humans and cynomolgus monkeys – the model animal tested prior to the clinical trial. The drug was designed for the CD28 receptor on T cells. The monkeys’ receptors closely resemble those found in humans. However, unlike these monkeys, humans have other immune cells that carry CD28. The trial participants received a starting dosage that was 0.2 per cent of what the monkeys received in their final tests, but failure to take these additional receptors into account meant a dosage that was supposed to occupy 10 per cent of the available CD28 receptors instead occupied 90 per cent. After the event, a Russian inventor purchased the commercial rights to the drug and renamed it TAB08. It has been further developed by Russian company, TheraMAB, and TAB08 is reportedly in Phase II clinical trials.

HUMAN-ON-A-CHIP AND ORGANOID PROJECTS

While animal testing has been a powerful and useful tool for determining safe usage for pharmaceuticals and other types of chemicals, it is also a cruel and imperfect practice. Moreover, it typically only predicts 30-60 per cent of human responses to new drugs. Nanotechnology and other emerging innovations present possibilities for reducing, and in some cases eliminating, the use of animal models.

People for the Ethical Treatment of Animals (PETA), still better known for its publicity stunts, maintains a webpage outlining a number of alternatives including in silico testing (computer modelling), and, perhaps most interestingly, human-on-a-chip and organoid (tissue engineering) projects.

Organ-on-a-chip projects use stem cells to create human tissues that replicate the functions of human organs. Discussions about human-on-a-chip activities – a phrase used to describe 10 interlinked organ chips – were a highlight of the 9^th World Congress on Alternatives to Animal Testing held in Prague, Czech Republic, last year. One project highlighted at the event was a joint US National Institutes of Health (NIH), US Food and Drug Administration (FDA) and US Defense Advanced Research Projects Agency (DARPA) project led by Dan Tagle that claimed it would develop functioning human-on-a-chip by 2017. However, he and his team were surprisingly close-mouthed and provided few details making it difficult to assess how close they are to achieving their goal.

By contrast, Uwe Marx – Leader of the ‘Multi-Organ-Chip’ programme in the Institute of Biotechnology at the Technical University of Berlin and Scientific Founder of TissUse, a human-on-a-chip start-up company – claims to have sold two-organ chips. He also claims to have successfully developed a four-organ chip and that he is on his way to building a human-on-a-chip. Though these chips remain to be seen, if they are, they will integrate microfluidics, cultured cells and materials patterned at the nanoscale to mimic various organs, and will allow chemical testing in an environment that somewhat mirrors a human.

Another interesting alternative for animal testing is organoids – a feature in regenerative medicine that can function as test sites. Engineers based at Cornell University recently published a paper on their functional, synthetic immune organ. Inspired by the lymph node, the organoid is comprised of gelatin-based biomaterials, which are reinforced with silicate nanoparticles (to keep the tissue from melting when reaching body temperature) and seeded with cells allowing it to mimic the anatomical microenvironment of a lymphatic node. It behaves like its inspiration converting B cells to germinal centres which activate, mature and mutate antibody genes when the body is under attack. The engineers claim to be able to control the immune response and to outperform 2D cultures with their 3D organoid. If the results are reproducible, the organoid could be used to develop new therapeutics.

Maryse de la Giroday is a science communications consultant and writer.

Full disclosure: Maryse de la Giroday received transportation and accommodation for the 9^th World Congress on Alternatives to Animal Testing from SEURAT-1, a European Union project, making scientific inquiries to facilitate the transition to animal testing alternatives, where possible.

ETA July 1, 2015: I would like to acknowledge more sources for the information in this article,

Sources:

The guinea pigging term, the ‘professional aspect, the Northwick Park story, and the Guinea Pig Zero magazine can be found in Carl Elliot’s excellent 2006 story titled ‘Guinea-Pigging’ for New Yorker magazine.

http://www.newyorker.com/magazine/2008/01/07/guinea-pigging

Information about the drug used in the Northwick Park Hospital disaster, the sale of the rights to a Russian inventor, and the June 2015 date for the current Phase II clinical trials were found in this Wikipedia essay titled, TGN 1412.

http://en.wikipedia.org/wiki/TGN1412

Additional information about the renamed drug, TAB08 and its Phase II clinical trials was found on (a) a US government website for information on clinical trials, (b) in a Dec. 2014 (?) TheraMAB advertisement in a Nature group magazine and a Jan. 2014 press release,

https://www.clinicaltrials.gov/ct2/show/NCT01990157?term=TAB08_RA01&rank=1

http://www.theramab.ru/TheraMAB_NAture.pdf

http://theramab.ru/en/news/phase_II

An April 2015 article (Experimental drug that injured UK volunteers resumes in human trials) by Owen Dyer for the British Medical Journal also mentioned the 2015 TheraMab Phase II clinical trials and provided information about the information about Macaque (cynomolgus) monkey tests.

http://www.bmj.com.proxy.lib.sfu.ca/content/350/bmj.h1831

BMJ 2015; 350 doi: http://dx.doi.org.proxy.lib.sfu.ca/10.1136/bmj.h1831 (Published 02 April 2015) Cite this as: BMJ 2015;350:h1831

A 2009 study by Christopher Horvath and Mark Milton somewhat contradicts the Dyer article’s contention that a species Macaque monkey was used as an animal model. (As the Dyer article is more recent and the Horvath/Milton analysis is more complex covering TGN 1412 in the context of other MAB drugs and their precursor tests along with specific TGN 1412 tests, I opted for the simple description.)

The TeGenero Incident [another name for the Northwick Park Accident] and the Duff Report Conclusions: A Series of Unfortunate Events or an Avoidable Event? by Christopher J. Horvath and Mark N. Milton. Published online before print February 24, 2009, doi: 10.1177/0192623309332986 Toxicol Pathol April 2009 vol. 37 no. 3 372-383

http://tpx.sagepub.com/content/37/3/372.full

Philippa Roxbuy’s May 24, 2013 BBC news online article provided confirmation and an additional detail or two about the Northwick Park Hospital accident. It notes that other models, in addition to animal models, are being developed.

http://www.bbc.com/news/health-22556736

Anne Ju’s excellent June 10,2015 news release about the Cornell University organoid (synthetic immune organ) project was very helpful.

http://www.news.cornell.edu/stories/2015/06/engineers-synthetic-immune-organ-produces-antibodies

There will also be a magazine article in International Innovation, which will differ somewhat from the blog posting, due to editorial style and other requirements.

ETA July 22, 2015: I now have a link to the magazine article.

Call for proposals to create in vitro inhalation tests for nanomaterial toxicity

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Tag Archives: in silico testing

Lungs: EU SmartNanoTox and Pneumo NP

A pragmatic approach to alternatives to animal testing

Maryse de la Giroday explains how emerging innovations can provide much-needed alternatives to animal testing. She also shares highlights of the 9^th World Congress on Alternatives to Animal Testing.

HARMFUL TO HEALTH

HUMAN-ON-A-CHIP AND ORGANOID PROJECTS

Call for proposals to create in vitro inhalation tests for nanomaterial toxicity

Maryse de la Giroday explains how emerging innovations can provide much-needed alternatives to animal testing. She also shares highlights of the 9th World Congress on Alternatives to Animal Testing.

HARMFUL TO HEALTH

HUMAN-ON-A-CHIP AND ORGANOID PROJECTS

Maryse de la Giroday explains how emerging innovations can provide much-needed alternatives to animal testing. She also shares highlights of the 9^th World Congress on Alternatives to Animal Testing.