New Year’s reads: having a blastema, gene therapy cost, pathogen lab escape data

Years ago I wrote about how I wished humans could form a blastema, which is a special area of regeneration near an injury that drives tissue replacement.

For example, when a lizard loses its tail to a pursuing bobcat, if it can regrow a new one that process will depend on a blastema. The same goes for salamanders with a lost leg or hand. Sadly, we humans can’t regrow a lost hand or even a finger. We only have one extra set of teeth, whereas some other animals like sharks make new teeth throughout life. 

It is thought that our limited regenerative capacity as a species may in part relate to the molecular and cellular safeguards we have in place to prevent cancer.

Let’s start with news on a new paper on blastema.

Blastema in jellyfish regeneration

Study identifies two stem cell types driving jellyfish tentacle growth, News Medical. Whenever I see stem cells and jellyfish mentioned together I think of the so-called immortal jellyfish.

While I doubt that any jellyfish are truly immortal, they are way better than humans at regeneration. (how could mortal humans know that something else is immortal for sure?)

As with other regenerative organisms, jellyfish form a blastema after injury. Not surprisingly, the blastema has stem cells driving regeneration. One of the interesting questions in this area of regenerative research is the extent to which existing stem cells are mobilized at the blastema versus dedifferentiation occurring there.  For example, in the latter scenario, existing differentiated cells may turn back into stem cells needed to regrow a tentacle.

Here’s the original research article in PLOS Biology: Distinct stem-like cell populations facilitate functional regeneration of the Cladonema medusa tentacle.

This kind of model organism research not only advances knowledge but also may have clinical impact for people. So, again, how do we make humans respond to injury with a functional blastema?

Other recommended reads

• What a new genetic therapy should teach us about biomedical ‘progress’, WaPo. This article rightly discusses the issue of cost and access to cutting-edge medical therapies like Casgevy for sickle cell. Both cell and gene therapies are expensive. For context, see our 2024 post on stem cell therapy cost more generally.
• N.I.H.’s New Leader Wants to Broaden Participation in Medical Research, NYT.  The new leader is Dr. Monica M. Bertagnolli.
• Laboratory-acquired infections and pathogen escapes worldwide between 2000 and 2021: a scoping review, The Lancet Microbe.