What to read when there are almost an endless number of stem cell and regenerative medicine pubs? Here are some suggestions including what I would say is a very unusual Nature paper on making egg cells from stem cells. If this could be done safely with human cells all the way to functional eggs, would you consider stem cell-related fertility treatments to be “Regenerative Medicine”?
structure at day 14 of culture are shown. A similar result was observed in all 26
follicles tested. Scale bar, 20 μm.” Hamazaki et al Nature Fig 2b screenshot. Induction of oocyte-like structures from ES cells by reprogramming.
Regenerative medicine and stem cell pubs
- Reconstitution of the oocyte transcriptional network with transcription factors, Nature. I’d call this one, which is Hamazaki, et al, the pub of the week at least, maybe of the last few months. The money quote from the paper, “we identified eight transcription factors, each of which was essential for the transition from primordial to primary follicle. Notably, enforced expression of these transcription factors swiftly converted pluripotent stem cells into oocyte-like cells that were competent for fertilization and subsequent cleavage.” So this is reprogramming toward an egg. What are the 8 transcription factors? The cocktail, which they call PPT8, includes these genes: NOBOX, FIGLA, TBPL2, SOHLH1, STAT3, DYNLL1, SUB1, AND LHX8. It’s not surprising there’s little overlap with pluripotency factors given that these are oocyte-inducing genes. See Fig. 2g above. Can this mouse study be repeated using human cells? I’ve just started reading the article so I’m also wondering if this reprogramming to an egg-like state can be done only with pluripotent cells as starting material or not. On a skim I don’t see that this article tries somatic cells alone. We’ll see. I’ve covered the more general area of trying to make gametes from stem cells for many years including work via IPS cells and differentiation into primordial germ cells. For example, this article: Are babies from same-sex couples possible?
- Embryonic Stem-Cell-Derived Extracellular Vesicles Maintain ESC Stemness by Activating FAK, Developmental Cell. Are extracellular vesicles the same as exosomes? Does the nomenclature matter?
- Retraction of Cancer-Related Mutations Identified in Primed Human Pluripotent Stem Cells, Cell Stem Cell, leads to a new letter from the authors. Here’s the retraction notice. The authors note that a large amount of MEF/feeders material seems to have confounded their initial results. I’m still mulling over whether this makes me less concerned about the possibility of mutations cropping up during reprogramming or not.
- Competition between PRC2.1 and 2.2 subcomplexes regulates PRC2 chromatin occupancy in human stem cells, Molecular Cell.
- Effects of Cryopreservation on Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes for Assessing Drug Safety Response Profiles, Stem Cell Reports. Freezing cells, whether stem cells or others, can substantially change their properties, but we can’t just continually grow them too long or they acquire mutations. Solutions?
Stem cell media
- Eight Genes Convert Mouse Stem Cells to Egg-Like Cells, GEN. See original Nature article in the above section.
- Hadassah Medical Center and Neurogenesis Announce Groundbreaking Results from a Phase 2 Study in Progressive Multiple Sclerosis treated with NG-01 Autologous Cells Therapy
Supplements take hits
- New from NIH Director Francis Collins’ blog: Study Finds No Benefit for Dietary Supplements.
- I recently went through the supposed brain supplement Prevagen and found reasons to be concerned about their advertising claims and also about potential risks. There are also many so-called “stem cell supplements” on the market that also seem unlikely to offer any benefit and could also pose risks.