What do we know about the long-term outlook for TRC hairs?

I’m generally curious about what we’re getting. Do we know of any probable drawbacks to this in the long-term sense? I’m thinking of the (lifetime) performance of the new/revived follicles.

I know that a lot of cloned living things of various types (both individual body parts and entire living organisms) seem to be prone to a common issue: The “new” stuff can sometimes show signs of a diminished lifespan that roughly corresponds to how “old” the donor tissue originally was at the time it was cloned.

Or if not full-blown early cellular death, then just premature aging. Parts of the cloned item’s lifetime behavior start fouling up early along the same lines. (Dolly the sheep’s early arthritis, etc.)

So, Is there any amount of this issue that may play into the results of the current HM efforts? If so then I doubt there has even been enough time for the researchers to see it coming. Anybody know or suspect anything?

Human hair cells put in immuno-deficient mice have grown and cycled at least once. Mice dont live very long though, so several cycles hasn’t been seen.

However, nobody has any reason to think that they wont. Its not an issue that anyone seems concerned about.

Cal, the first thing everyone should know is that the term “hair cloning” is actually a misnomer. This has been pointed out numerous times, by numerous experts, and also many times here on HairSite and other sites. Companies like Intercytex don’t even use the term “hair cloning” to describe their cell-based hair regeneration procedures, because it is scientifically inaccurate.

Nonetheless, the term “hair cloning” has been used extensively in the popular media for a number of years, to refer to what we, on HairSite, call “hair multiplication”, and which companies like ICX are now calling “follicular neogenesis” or “follicular cell regeneration”.

In fact, “hair cloning” has little in common with cloning of, say, an animal or lower organism, like bacteria.

The TRC procedure is a form of cell therapy in which cells are harvested from an organ (your donor hair follicles), dissociated, cultured in vitro (in a “petri dish” or the equivalent), and then injected or re-implanted into the scalp.

By contrast, the technical, textbook definition of cloning refers to the replication of DNA, or a cell nucleus (which contains DNA), into one or more copies. The copies are then coaxed into growing into an entire new organism. For instance, a mammal can be cloned by removing a nucleus, containing all its chromosomes (that is, one of each chromosome), from a “somatic” (or body) cell, and implanting the nucleus into a “germ” (or reproductive) cell, like an egg cell. This produces a situation similar to a fertilized egg, and if the egg divides mitotically, it can potentially grow into a new organism – a genetically identical copy of the original mammal, or whatever.

Note that TRC and other HM procedures are not creating a new organism, but just manufacturing new organs from somatic cells. The germ cells, or reproductive cells, don’t even come into play.

So, technically, TRC (and all HM) is not cloning. Since there is no removal of a nucleus and no creation of a genetic copy of an entire organism, the same concerns about the fidelity of the “genetic copy” don’t really come into play.

Yes, you are still making a copy, but not of an entire organism. You are making copies of somatic cells (the donor cells). But the human body makes copies of its own cells anyway, all the time. All kinds of cells all over the body normally undergo cell division to create more cells of the same kind. So, really, TRC and all forms of HM are nothing unusual. They are nothing fundamentally different from what the body does itself anyway. HM just changes the way and the place that this is done. Instead of those donor follicles dividing and creating new cells which remain inside the donor follicles, cells are being extracted, physically removed from the donor follicles, and caused to multiply into copies in a laboratory.

I appreciate the quick & thorough responses.

Yeah, I shouldn’t have talked about “cloning” so much. I actually was aware of the difference already. But I wondered if the TRC method could concievably be prone to similar problems as a full-blown “wipe out the nucleus and then replace it” cloning job. The TRC method would still be artificially duplicating (or at least causing vastly increased replication of) a part of a human body. They’re also doing this replicating partway through the cells’ lifespans and then trying to make everything work for some entirely new growths (follicles).

I guess I still have some gut-level mistrust of how the ICX-TRC deal could be providing (half a lifetime?) of further hair growth with only what is projected to be a one-time infusion of transplanted/replicated cells. It just seems like we’re asking for some sort of built-in limit on the lifespan of the cells/tissue to rear its ugly head later on. That’s so often the case when messing with living things; whenever we try to expand the lifespan of something the “free lunches” often bring up another shoe that drops eventually.

Maybe I’m just being pessimistic, but I’m running out of reasons to think that this current ICX-TRC project won’t really work. Getting hopes up can be dangerous in the MPB world and I don’t wanna get disappointed.

» I guess I still have some gut-level mistrust of how the ICX-TRC deal could
» be providing (half a lifetime?) of further hair growth with only what is
» projected to be a one-time infusion of transplanted/replicated cells. It
» just seems like we’re asking for some sort of built-in limit on the
» lifespan of the cells/tissue to rear its ugly head later on. That’s so
» often the case when messing with living things; whenever we try to expand
» the lifespan of something the “free lunches” often bring up another shoe
» that drops eventually.

I think I’ve seen somewhere Intercytex stating that this won’t be a problem because the number of cell generations required in HM is relatively small.

Using my own calculations: With 10 generations you get a multiplication factor of about a 1000 (2^10 = 1024) and they’re taking cells from about 100 hairs. So that’s enough for 100,000 hairs?

» Maybe I’m just being pessimistic, but I’m running out of reasons to think
» that this current ICX-TRC project won’t really work. Getting hopes up can
» be dangerous in the MPB world and I don’t wanna get disappointed.

There are plenty of reasons to remain pessimistic. However, I don’t think the hairs thinning over time is any where near the top of the list of what people should worry about. If the hair cells lose viability, just go get some more injections. Each time will be cheaper and better as scientists continue to refine the technique over time. :slight_smile: