If you are sick of the general news lately, I recommend turning to the wonder of cool science like the thought-provoking data in the duo of new stem cell pubs discussed below.
A team led by Alfonso Martinez-Arias reports new findings in their Nature letter in the growing area of synthetic or artificial embryo-like structures. See my review of a paper on this kind of research from last year. Their new piece Beccari, et al., entitled, “Multi-axial self-organization properties of mouse embryonic stem cells into gastruloids” describes production of embryo-like structures called gastruloids.
These structures, “display the hallmarks of axial gene regulatory systems as exemplified by the implementation of collinear Hox transcriptional patterns along an extending antero-posterior axis.”
Who doesn’t like Hox genes?
Work in this broad area on human embryo-like structures is cool, but raises thorny ethical issues.
See part of Figure 1a from Beccari here, showing the “headless little bananas”, meaning the gastruloids. I think the most remarkable thing here is the self-organizing properties of mESCs.
Skeletal stem cells
When I first saw this other new paper “Identification of the Human Skeletal Stem Cell” in this case in Cell my initial reaction was along the lines of, “Wait, haven’t people already found skeletal stem cells before?”
The authors say the answer is “no.”
Cells broadly called MSCs can make bone cells, but this paper from a team led by Michael T. Longaker of Stanford, seems to report something more specific: defined skeletal stem cells that are unique.
From the abstract, we have the main points in a nutshell, “Here, we report the isolation of a self-renewing and multipotent human skeletal stem cell (hSSC) that generates progenitors of bone, cartilage, and stroma, but not fat.” It’s interesting that fat is kind of distinct here. Often times people say MSCs can make bone or cartilage and fat. They also found that the hSSC can support maintenance of hematopoietic stem cells. In addition the paper interestingly compares findings from mouse and human types of cells.