Cells Weekly is a digest of the most interesting news and events in stem cell research, cell therapy and regenerative medicine. Cells Weekly is posted every Sunday night!
1. First live birth using mitochondrial replacement technique
International team of researchers reported this week first live birth of a boy, using mitochondrial replacement technique – spindle nuclear transfer (SNT). His mother is a carrier of mutated mitochondrial DNA, known as Leigh syndrome. SNT procedure took place in Mexican clinic, child was born in New York to a couple from Jordan.
New Scientist broke the news, causing an explosion in mass media:
Zhang has been working on a way to avoid mitochondrial disease using a so-called “three-parent” technique. In theory, there are a few ways of doing this. The method approved in the UK is called pronuclear transfer and involves fertilising both the mother’s egg and a donor egg with the father’s sperm. Before the fertilised eggs start dividing into early-stage embryos, each nucleus is removed. The nucleus from the donor’s fertilised egg is discarded and replaced by that from the mother’s fertilised egg.
But this technique wasn’t appropriate for the couple – as Muslims, they were opposed to the destruction of two embryos. So Zhang took a different approach, called spindle nuclear transfer. He removed the nucleus from one of the mother’s eggs and inserted it into a donor egg that had had its own nucleus removed. The resulting egg – with nuclear DNA from the mother and mitochondrial DNA from a donor – was then fertilised with the father’s sperm.
Many researchers think that the case could change attitude toward mithochondrial replacement therapy and impact regulations. On the other hand, this “first case” caused some criticism for taking advantage of weak regulatory system (or its absence) and for ethical issues.
2. Engineering T cellbots
Wendell Lim’s lab from USCF continue to explore the ways to control CAR T-cells precisely, using “magic of synthetic biology”. Previously, his group described synthetic Notch receptor on CAR T-cells. In the new Cell paper, they made polyfunctional synNotch T-cells, responsive to environment.
We show that synNotch receptors can be used to sculpt custom response programs in primary T cells: they can drive a la carte cytokine secretion profiles, biased T cell differentiation, and local delivery of non-native therapeutic payloads, such as antibodies, in response to antigen. SynNotch T cells can thus be used as a general platform to recognize and remodel local microenvironments associated with diverse diseases.
Importantly, new type of synNotch T-cell can make drugs, such as check point inhibitors. Lim started to use new term “cellbots” in the media.
Read more from NIHilist’s Immunology blog.
3. Results of Phase 2 CAR-T cell trial in lymphoma
US-based company Kite Pharma announced preliminary results of their Phase 2 clinical trial, assessing efficacy of CD19 CAR-T cells in patients with lymphomas. Results of this trial is a big deal, because it is a pivotal trial, data from which will be used for BLA submission to FDA and market approval. The results are positive, but many people expected better outcomes. Combined data from different types of lymphoma demonstrated 44% of overall survival and 39% of complete remission. The caveat is – at 3 months readout. There is some skepticism in the field about durability of responses. Field is suffering right not from relapse rates. It is also unclear whether FDA will be OK about 3-month data or will ask to wait until 6-month readout.
Read nice summary on EP Vantage.
4. Bioprinted hyperelastic material for bone healing
Researchers from Northwestern University created new synthetic biomaterial with osteoregenerative properties. Importantly, the material could be printed rapidly on demand:
We evaluated HB in vivo in a mouse subcutaneous implant model for material biocompatibility (7 and 35 days), in a rat posterolateral spinal fusion model for new bone formation (8 weeks), and in a large, non-human primate calvarial defect case study (4 weeks). HB did not elicit a negative immune response, became vascularized, quickly integrated with surrounding tissues, and rapidly ossified and supported new bone growth without the need for added biological factors.
Read more from Science News.
5. Ups and downs of NgAgo genome editing
Kate Qin Zhao wrote on a Medium great essay about new genome editing technique, called NgAgo. What I like especially about this piece is an emphasis on role of social media in reproducibility efforts:
Through this global replication effort of NgAgo, we can see more clearly that, the way we share information on scientific research has forever changed in the age of social media.
Social media has become a great vehicle to quickly promote a scientific discovery/invention. But, it also could be a double-edged sword. Once the message is out, if there is a problem, hiding it from the public will no longer be easy.
6. Ogawa-Yamanaka Stem Cell Prize 2016
Gladstone Institutes held this week annual ceremony for Ogawa-Yamanaka Stem Cell Prize award. This year awardee was stem cell researcher from Harvard University Douglas Melton.
Here is Melton’s talk: