I’m subscribed to some search feeds at Pubmed. Here’s what caught my eye this week in the Stem Cells feed:
There were 35 new articles this week, only two of which were open access.
Ledford H. Doubts raised over stem-cell marker. Nature. 2007 Oct 11;449(7163):647. PMID: 17968390 Related Articles
This is a review of a couple papers about Oct4, which I’m linking to instead of the primary articles because the Cell Stem Cell papers aren’t accessible to many whose libraries have foregone the tens of thousands of dollars charged by Cell Press for online access. In short, Oct4 has been found in peripheral blood mononuclear cells, which are terminally differentiated, so Oct4’s status as a stem cell marker may need to be revised. Conversely, Rudy Jaenisch’s lab at the Whitehead Institute hasn’t searched exhaustively for Oct4 in Adult Stem Cells and found nothing.
Karnoub AE, Dash AB, Vo AP, Sullivan A, Brooks MW, Bell GW, Richardson AL, Polyak K, Tubo R, Weinberg RA. Mesenchymal stem cells within tumour stroma promote breast cancer metastasis. Nature. 2007 Oct 4;449(7162):557-63.
PMID: 17914389 Related Articles
The paper about MSCs enhancing metastasis of breast cancer tumors that I wrote about two weeks ago has hit Pubmed.
Lange C, Cakiroglu F, Spiess AN, Cappallo-Obermann H, Dierlamm J, Zander AR. Accelerated and safe expansion of human mesenchymal stromal cells in animal serum-free medium for transplantation and regenerative medicine. J Cell Physiol. 2007 Oct;213(1):18-26. PMID: 17458897 Related Articles
This is a German group, and judging by the citation reports provided by Thompson, Germany is second to the US in adult stem cell research. They have developed a GMP-compatible serum-free culture system for culturing MSCs. They tested it the usual way, by doing surface marker profiling and in vitro differentiation, but since the correlation between those things and the theoretical “reparative capacity” of a stem cell isn’t well established, it’s really anyone’s guess whether the two methods really do produce a bioequivalent product. Also, since their culture system still includes 5% thrombocyte concentrate lysate, it’s just xenogenic pathogen free, not totally free of the risk of harboring transmissible pathogens, nor is it a chemically-defined medium, which would be the real breakthrough.
Claase MB, de Bruijn JD, Grijpma DW, Feijen J. Ectopic bone formation in cell-seeded poly(ethylene oxide)/poly(butylene terephthalate) copolymer scaffolds of varying porosity. J Mater Sci Mater Med. 2007 Jul;18(7):1299-307. Epub 2007 Feb 1. PMID: 17268874 Related Articles
If you’re looking for a good assay, it seems to me that ectopic bone formation, complete with bone marrow, would be a pretty good bioequivalence assay for a bone-marrow derived stem cell. I don’t know about you, but it seems to me that bone marrow derived cells reforming bone marrow is about as good as it gets. That someone who comes from Friedenstein‘s lab has published this assay in Methods tends to give a little weight to this, as well.
That’s all I found this week, but if I missed anything, let me know!