When immunology researchers talk about “T cell stem cells” (or stem T cells or T memory stem cells), are they talking more generally about hematopoietic stem cells? No, because those have much broader potential.
The most primitive stem cell for T cells can make all the various kinds of mature T cells. It seems like there are almost a dozen kinds of T cells recognized these days.
T cell stem cells and the thymus as a possible anti-aging organ
What the immunology field considers a stem cell for T cells appears to be what I would have in the past mostly thought of as the earliest T cell progenitor. Now I guess I’ve become more flexible in how I think about progenitor vs. stem cell.
A new Cell paper provides fresh insights into how to identify so-called T cell stem cells: LEF1 and niche factors determine T cell stemness across chronic diseases.
They identified LEF1 as a key T cell stemness factor. The paper also provides cool insights into how these LEF1+ cells may factor into human disease.
Do you think they are studying T cell “stem cells” or “progenitors”? Does it matter?
Toward the end they write (ASC are adult stem cells, emphasis mine):
“ASCs of various tissues (intestine, skin, muscle; Figure 7C) are required for tissue homeostasis, regeneration, and repair: adult stem cells are capable of self-renewal and differentiation into progenitor cells (transit amplifying cells), which then further undergo rapid differentiation into many differentiated progenies (SC→PRO→DIFF). Our study describes that similar modules exist for T cells in autoimmunity and chronic infection (TSC→TPRO→TDIFF; Figure 7C) to sustain antigen-specific immune responses through an epigenetically encoded core program of T cell stemness, with LEF1 as the key TF defining the TSC state across chronic diseases.”
Since these T cell “stem cells” can differentiate into multiple distinct T cell types, is that a form of multipotency? These cells reportedly have some other properties usually associated with stem cells like asymmetric division.
Speaking of T cells, there’s growing interest in targeting the thymus to fight aging. This organ normally shrinks as we age and it was assumed that was just how it was, but retained thymic function may be important for healthy aging. What if you could regenerate the thymus in aging adults to be larger and more functional? Or transplant “younger” thymic tissue back into such folks? Would it be helpful for healthy aging?
More from Nature: Could this mysterious disappearing organ hold the key to longevity?
More recommended reads
- Evolution of a core ribosomal innovation in octopus, bioRxiv. This is cool and may tie into the evolution of the amazing octopus brain. I met someone who has stopped eating octopus at restaurants because of how smart these creatures are. I don’t really eat octopus anyway, but it’s interesting that octopi are getting more respect for their intellects.
- Dr. Peter Marks On Why Gene Therapy May Need A New Regulatory Playbook, Cell & Gene. It’s getting less weird to see news on Marks now that he’s not leading CBER. Who is the acting leader of CBER now? Does anyone seem to care?
- Divergent cell-type specific hypoxia responses in human stem cell-derived and primary islets, Scientific Reports.
- Human embryonic stem cell-derived dopaminergic cells for Parkinson’s disease: a phase 1/2 open-label trial, Nat Med.
A thought on the uber-rich wasting billions at the expense of millions of people
A thought came to mind a few weeks back about ethics in the longevity world.
Imagine if the richest/most powerful few people like Bezos, Zuckerberg, Musk, etc. some day spend billions over time trying to extend their lives by maybe a year or two (even that is iffy I know) via “longevity” when the same money could’ve literally saved the lives of tens of millions of people around the world including a million or more children. Wouldn’t that be unethical?