Advances in transplantable organ preservation, grinders get night vision, and using genehacking to treat lymphoma.

31 March 2015

Organ transplants are a fairly hairy aspect of the medical practice and are a crapshoot even with the best medical care money can buy. Tissue matching viable organs seems about as difficult as brute-forcing RSA keys due to the fact that, at the proteomic level even the slightest mismatch between donor and recipient (and there will always be some degree of mismatch unless they are identical twins) will provoke an immune response that will eventually destroy the transplanted organ unless it's not kept under control. Additionally, unless the organ is perfectly cared for prior to installation the tissues will begin to degrade which will further provoke the recipient's immune system into active response. All things being equal (more or less) a new advance in biotechnology seems to have at least brought this last detail under better control. A new device called the XVIVO Perfusion System uses a centripital pump to move chilled oxygenated fluid through the circulatory system of the organ to keep the cells alive while during the time that the donor lungs were carefully assessed for suitability. The process bought those lungs an extra handful of hours of viability prior to implantation. Far from being a laboratory experiment the XPS was used to save the life of one Kyle Clark in Michigan. Clark was born with cystic fibrosis, a genetic disease which causes progressive organ damage, particularly in the lungs. Lung transplants are a not uncommon course of treatment for CF patients. With a great deal of luck CF patients can live well into their 40's or 50's but it's far from a sure thing. When suitable donor lungs were located for Clark the XPS was used to preserve them so that they could be evaluated more carefully, including microscopic examination to ensure that carbon dioxide was being exchanged for oxygen properly inside the life-support device. It's too early to tell but it looks like the transplant has been a success, and it would seem that he has many years of life ahead of him.

Some years ago the novelist Warren Ellis postulated a subculture called grinders in one of his works - people who hack their biology in the same way that one might hack on computers or software. This can involve everything from building and installing DIY implants to using quantified self techniques to optimize one's performance (arguably - I'd call it "soft grinding" because it's usually noninvasive, but opinions probably differ). Last week a group of grinders called Science for the Masses published a paper describing the results of a unique experment - they induced acute night vision in a baseline human through chemical means. SftM dripped a solution of an organic photosensitizing compound called Chlorin E6, saline, and the organic solvent DMSO into the eyes of test subjects under controlled conditions. The hypothesis they were testing was that the Chlorin E6 would permeate the subject's retinas (potentiated by the DMSO, which accelerates uptake of chemical compounds into the human body) and cause the photosensitive pigments therein to be more responsive to light. The Science for the Masses team observed that positive effects began within one hour of administration, necessitating that the test subjects wear both black scleral lenses and sunglasses to protect their eyes from overexposure to light. This was, after all, an experiment... adjusting to the retinal alterations took about two hours, after which their visual acuity was tested after dark somewhere in a grove of trees. Recognition of symbols at distances of 10 meters was consistently better than that of four unaugmented test subjects. In other trials, test subjects were consistently able to recognize other people who moved at whim through the same grove of trees after dark at distances of between 25 and 50 meters. Statistically speaking, the control subjects had a 33% success rate, while test subjects augmented with Ce6 had a 100% success rate. 20 days after the tests, no ill effects were reported.

Early last year I wrote a brief post about CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) technology, which exploits a curious property of DNA that makes it easy to precisely target individual genes in the genomes of living things. Just a year later CRISPR technology is being tested in the field of oncology for treating certain forms of lymphoma. At the Walter and Eliza Hall Institute of Medical Research in Melbourne, Australia a research team published a paper in Cell Reports in which they had successfully destroyed cultures of Burkett lymphoma cells in vitro using the CRISPR/Cas9 technique. Medical science has isolated a gene called MCL-1 which is essential for the metabolism of cancerous cells in humans; the CRISPR/Cas9 technique was used to delete that gene in the cells, thus killing them and causing the cultures to collapse. Hypothetically speaking (and I'm not an oncologist so it would be irresponsible of me to not caveat this), noncancerous cells should not have the MCL-1 gene so it might be possible to unleash a treatment systemically but only the intended cancerous cells would be destroyed (if anyone knows for sure, please leave a comment!). The research team itself called this a proof-of-concept test so in honesty it can't be called a treatment yet, only steps toward a possible one in the future. Still, it seems like a solid step forward that might have implications in other fields of medicine.