A paralysed man can stand on his own after receiving an injection of neural stem cells to treat his spinal cord injury. The Japanese man was one of four individuals in a first-of-its-kind trial that used reprogrammed stem cells to treat people who are fully paralysed.

Yet more “miracle stem cell cure reverses paralysis” hype…

Have heard this many times over the years, it won’t materialse for decades at best but hype articles will continue to be written about it

“Reprogrammed or induced pluripotent stem (iPS) cells are created by reverting adult cells to an embryonic-like state, from which they can be coaxed to develop into other cell types.

In this trial, iPS cells derived from a donor were used to create neural precursor cells. Two million of these were injected into each patient’s injury site, in the hope that they would eventually develop into neurons and glial cells.”

“Recipients were given immune-suppressing drugs to prevent their bodies from attacking the cells for six months after the surgery.”

Cells from a donor are called allogeneic and cells from your own body are called autologous so these were allogeneic which is why they were prescribed immune suppressing drugs for six months. The donor cells eventually get swept away by the body’s immune system which is why they only had to take the immune suppressing drugs for 6 months. That or they die, they certainly don’t permanently engraft or else they’d have to take the immune drugs permanently.

I bet these donor cells are mainly working via the paracrine function, the donor cells are secreting exosomes and it’s the exosomes that are stimulating repair. They’re secreting exosomes and growth factors for a few months or maybe even just a few weeks, and then they either die off or get swept away by the immune system. But it’s the goodies that they secrete which are stimulating the body to repair itself.

If you’re curious do some research into exosomes. Exosomes are f*cking revolutionary!!!

I asked Grok what the paracrine function is:

The paracrine function is the process by which cells secrete signaling molecules (exosomes, exosomes are also called extracellular vesicles, they’re about the size of a virus. Cells talk to each other by secreting exosomes. This is my human edit) that act on nearby target cells, influencing their function or behavior. In biological systems, this form of cell-to-cell communication is local, meaning the signaling molecules diffuse through the extracellular fluid to affect cells in the immediate vicinity rather than traveling through the bloodstream like hormones in endocrine signaling. Examples of paracrine signaling include immune cells releasing cytokines to attract other immune cells during inflammation, or neurons releasing neurotransmitters to stimulate adjacent neurons in synaptic transmission. The signaling molecules involved can vary widely, including growth factors, cytokines, or even gases like nitric oxide, which, for instance, induces vasodilation in nearby blood vessels. This local action distinguishes paracrine function from other signaling mechanisms, such as autocrine signaling (where cells affect themselves) or endocrine signaling (which acts over long distances). Thus, the paracrine function plays a critical role in processes like development, immune responses, and tissue repair by enabling precise, localized communication between cells.