3203 replies to this topic

[Moondark]

So..hydrogel can give us a free scar healing or not? Bout follicules i dont care, the importantis makenew skin normal...

[seabs135]

rimram, on 25 May 2012 - 04:18 AM, said:

Hey guys,

First of all, I really hate to be negative, since hope is such an important part in coping with scarring. That said, there's one thing that bothers me about the Gerecht et al hydrogel paper, and it would be interesting to hear what you guys think about it. Here's a quote:

Quote

Moreover, we observed a significant increase in the number of
hair follicles (Fig. 7A, iii). Indeed, when the treatment continued
for extended periods, we observed hair growth in the center of
hydrogel-treated wounds (Fig. 7B).

First, notice that they are only talking about an increase in the number of HFs. The fact is that hair follicles are already known to regenerate in mammals given that the wound is large enough. This was recently popularized in a study by Ito et al that is referenced in the Gerecht paper and that has also laid the foundations for a biotech start-up, Follica, that tries to take advantage of this fact to treat various forms of alopecias (hair loss from scarring included.)

However, as it seems, one of the big problems is that the "regenerative response," if you will, is only strong enough to induce new follicle formation in the center of the wound bed. Notice that the quote above explicitly mentions just the center of the hydrogel-treated wounds. This implies that the regenerated skin will be surrounded by a scarred margin if the procedure is carried out as a full thickness excision, as in the pic below (from Follica's most recent patent):



Nevertheless, there's a lot of positives coming from this hydrogel imo. For example, afaik, Follica has never been able to regenerate pigmented hair follicles, so this is clearly a testament to the merits of the hydrogel, whether it accomplishes this by increasing melanocyte SC motility or even by dedifferentiating the wound bed to such a degree that MCSCs are formed anew. It's also possible that the problem with the scarred margin can be solved by dermabrading the surrounding area of the excision so as to enlarge the regenerating zone to include the borders as well, or perhaps by limiting the use of the hydrogel to improving the healing in deeper types of dermabrasion for scars that don't go all the way through the skin.

Regarding the hair in the center. If you look at the paper they are highlighting the fact that when a scaffold finds it hard to be degraded/digested (like the control) then the neutrophils can’t digest well at the periphery of the scaffold (like the control) never mind the centre. And as such the centre of the wound is the place least likely to regenerate if the neutrophils cant break the periphery of the scaffold to enable fast reepithilization into the center. So when they are highlighting that hair grew in the middle of the hydrogel they are showing default logical proof that the 80:20 hydrogel was degraded fast to enable complete regeneration. As in the center, through the neutrophils degrading the 8020 hydrogel enabling fast reepithilization there was hair. This is different in the control scaffold were the neutrophils could not digest the periphery.

chuckstonchew, on 25 May 2012 - 12:03 PM, said:

^ In relation to the above post,
I saw this a while back as well and asked one of Gerecht's researchers about this statement when I contacted them. This was the convo:
......
ME: I was curious, does this mean that while the hydrogel initiated regeneration in the center of the wound of the full thickness excision, there was still a scarred area that encircled the newly regenerated skin?

REPLY: The burn size was 1.2cm in diameter, while we only cut off 0.8cm. So there was a rim left.

ME: Great. So all of the skin that was treated with hydrogel did regenerate then?

REPLY: At least we can say that the hydrogel promoted hair growth.
......

Kind of ambiguous reply there at the end, eh? Ugh. I don't know. It seems only time will tell...

It is not ambiguous. The treated center brought complete regeneration, hair and sweat glands do not grow in scar, and the untreated rim part behaved as an untreated part would.

Edited by seabs135, Today, 06:31 PM.

[alonso]

has anyone read this?
USE OF ERYTHROPOIETIN FOR SCAR-FREE HEALING OF WOUNDS OR TISSUE DEFECTS
http://patentscope.w...ueryString=a61k
is in another language

[Vladislav]

How would you like to have a face like this:





So that guy has one of the highest positions in the Ministry of Foreign Affairs in my country, he was born in 1973 and he is a univesity professor and a columnist in one newspaper and a president of one non-goverment organization, he is on the TV all the time as a political analyst, he has a wife and two children, here you can see his biography:
http://www.cnp.rs/en/pages/view/24