Stem Cells

Induced neural stem cells (iNSCs) hold promise for therapeutic transplantation, but their potential in this capacity has been limited by failed efforts to maintain such cells in their multi-potent NSC state. Now, Whitehead Institute scientists have created iNSCs that remain in the multi-potent state—without ongoing expression of reprogramming factors. This allows the iNSCs to self-renew repeatedly to generate cells in quantities sufficient for therapy.

Scientists have long theorized that the way in which the roughly three meters of DNA in a human cell is packaged to fit within a nuclear space just six microns wide, affects gene expression. Now, Whitehead Institute researchers present the first evidence that DNA structure does indeed have such effects—in this case finding a link between chromosome structure and the expression and repression of key genes.

Induced pluripotent stem cells (iPSCs) may hold the potential to cure damaged nerves, regrow limbs and organs, and perfectly model a patient’s particular disease. Yet these cells can acquire serious genetic and epigenetic abnormalities that lower the cells’ quality and limit their therapeutic usefulness. Now Whitehead Institute researchers have identified a cocktail of reprogramming factors that produces very high quality iPSCs.

Embryonic stem cell (ESC) research has been hampered by the inability to transfer research and tools from mouse ESC studies to their human counterparts, in part because human ESCs are “primed” and slightly less plastic than the mouse cells. Now researchers in the lab of Whitehead Institute Founding Member Rudolf Jaenisch have discovered how to manipulate and maintain human ESCs into a “naïve” or base pluripotent state similar to that of mouse ESCs without the use of any reprogramming factors.

Metastatic cancer cells, which can migrate from primary tumors to seed new malignancies, have thus far been resistant to the current arsenal of anticancer drugs. Now, however, researchers at Whitehead Institute have identified a critical weakness that actually exploits one of these cells’ apparent strengths—their ability to move and invade tissues. Their research could inform novel approaches to screening tumors for personalized therapy or to drugs that specifically target these cells.

The lab of Whitehead Institute Member Peter Reddien is introducing the scientific community to the three-banded panther worm (Hofstenia miamia), a small organism with the ability to regenerate any missing body part. As a model, Hofstenia could help further our understanding of regeneration, how its mechanisms have evolved over millennia, and what limits regeneration in other animals, including humans. 

Whitehead Institute researchers have used the gene regulation system CRISPR/Cas (for “clustered regularly interspaced short palindromic repeat/CRISPR-associated) to engineer mouse genomes containing reporter and conditional alleles in one step. Animals containing such sophisticated engineered alleles can now be made in a matter of weeks rather than years and could be used to model diseases and study gene function.