What does it mean?

[hairysituation]

I just checked out Histogen's website and I read this: "HSC's components have recently been shown to be critical for new hair follicle formation"

Is my English really bad or is this some negative news?

[gmonasco]

In this sense, "critical" means "necessary," so it's supposed to be a positive statement. As in, "We've discovered stuff that has to be present for new hair follicles to form."

[2020]

^ NEW hair follicles?
That is not how Histogen works. They won't be able to create BRAND NEW FOLLICLES, only to revive EXISTING ones with some kind of growth factors. Am I wrong?

[gmonasco]

Dr. Craig Ziering serves as the lead investigator of clinic trials for HSC. Not only has he found no adverse effects from the product’s clinical trials, but he has also noted that trials of the products have produced more hair with thicker hair shafts as well as completely new hair follicles in the areas treated with HSC.

http://www.zieringmedical.com/about-...bout-histogen/

[2020]

http://www.zieringmedical.com/about-...bout-histogen/

how could they grow COMPLETELY new follicles without existing stem cells in place?
Anyways, if that was true then this is bad news as you'll have thousands of new follicles in random patterns producing unevenly thin hair....

[gmonasco]

It's hard to tell whether they're using "new hair follicles" synonymously with "new hairs" or not. If HSC were prompting existing, non-producing follicles to start regrowing hair, those would be "new hairs," but they wouldn't technically be "new hair follicles."

[Pate]

how could they grow COMPLETELY new follicles without existing stem cells in place?
Anyways, if that was true then this is bad news as you'll have thousands of new follicles in random patterns producing unevenly thin hair....

But the stem cells are in place, as we know from Cotsarelis's work. What's missing is the chemical signals to get them to differentiate into the hair-producing cells. It could be that these growth factors are a necessary part of the chain, but that doesn't mean they are capable of inducing follicular neogenesis by themselves.

Also, the Ziering quote may not necessarily indicate the creation of brand-new follicles, it may just mean that hair follicles that were completely dormant and not producing any hair were reactivated. So it would appear that there was a new follicle there. The problem is that unlike Replicel, Histogen aren't actually injecting cells that they can track down later. They are just injecting growth factors so it'll be a lot more difficult to tell whether a hair that suddenly sprouts comes from a brand-new follicle or just one that was dormant.

Replicel on the other hand can tell whether it's a new follicle or a rejuvenated one, because the cells they inject into mice glow green.