I am attending the seminar and am trying in realtime to spit it back out to you…Ken Washenik is starting off with Cell therapy/cell multiplicaton.
Next will be holding solutions and other topics…
Dr. Washenik…
What is the regeneration properties of the hair follicle?
Plucked hairs regrow.
hair falls out… and it grows.
So the hair follicle is known to have regeneration properties.
Cells have to be trichogenic to be able to be specialized…
The dermal papilla has inductive properties to form new follicles.
Important cells within the follicle to create new follicles. Dermal cells and epidermal cell.
Disassociated follicular papilla and epidermal cells have been able to grow hair on mice.
One cell approach to cell multiplication.
Using dermal cell usage only. Dermal cells are inductive cells. They induce cell replication of the hair follicle.
One theory: Inject the dermal cells into the skin and a hair follicle grows right?
One experiment was to take several hairs, take the dermal papillas and create a hair from the dermal papillas.
This was in 1999. It worked in the mouse.
The two cell approach. Using dermal cells and epidermal cells.
Epidermal cells are hard to culture.
When you culture epidermal cells and dermal cells, mix them, plant them, they coalesce and form hairs.
When injected in the skin hair grows. But it grows erratically. hairs cells form by two weeks. actual follicles grow!
They begin to cycle… anagen/telogen occurs… At day 21 telogen occurs. Shedding cannot occur though… Because the follicles do not poke through the skin so an inflammatory reaction occurs. It then inhibits further growth.
Why does telogen occur so fast? Because the mice model is used. Mice hair cycles are extremely fast. And they all happen at the same time.
So they tried the experiment again with immunocompromised mice. To see if the inflammatory response.
going back to the first experiment first. If you poke a needle into the mass of hair, they can get through the kin and grow.
But the cycle is too fast.
So the problem is even though you can grow hair in culture and inject under skin, there are still issues with angles, control of growth, etc…
New research…
Wound formation in mice showed hair to form within the would during healing for some reason. That meant there is a different option to creat new hair outside of a culture.
So more research needs to go into this also.
So basically we have shown that we can grow hair in culture. We have good models in mice for several approaches. But we are still in the beginning stages of this fascinating research.
Questions??
No…
Next presentation.
Sarah Miller, Phd
Molecular controls of hair follicle development and hair growth.
What cells are important is hair?
Hair follicle development in mice:
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Most of the mouses skin is dedicated for hair development. Very highly densed packed.
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Surface dermal cells in the embryo of mice controls development of hair.
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The development of hair follicles are regulated then by intercellular signals. In other words, the dermis is talking to the epidermis during development, to create hair follicles.
technical difficulties at the moment…
What cells are important is hair?
Hair follicle development in mice:
-
Most of the mouses skin is dedicated for hair development. Very highly densed packed.
-
Surface dermal cells in the embryo of mice controls development of hair.
-
The development of hair follicles are regulated then by intercellular signals. In other words, the dermis is talking to the epidermis during development, to create hair follicles.
technical difficulties at the moment…
slides are out of order… waiting for continuation of speaker…
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WNT molecules are very important in hair follicle formation.
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WNT can cause hair follicle tumors. Hair follicle tumors are tumors of hair, and mostly hair particles… essentially a real tumor of no growth control.
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WNT inhibition can cause hair to stop growing.
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So WNT seems to to something in the future as a cell signal for follicles to grow or not grow.
Next topic…
Hair spacing… How does it occur on the molecular level.
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All has to do with cell signalling. She is speaking about the different cellular molecules that signal the uniform spacing of hair.
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Very complex. They are still learning what cell signal controls do what.
Hair spacing… How does it occur on the molecular level.
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All has to do with cell signalling. She is speaking about the different cellular molecules that signal the uniform spacing of hair.
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Very complex. They are still learning what cell signal controls do what.
She is now speaking about certain mutations in genes that stop hair growth or begin hair growth
Someone is asking a question…
Dr. Harris and me (me not pictured only my computer screen
She is really being technical… and now her computer crashed so I am waiting…
Now she is talking about the signals in the dermal Papilla that play important roles on hair development.
The speaker has finished. Basically she named all the molecules involved in the development of hair follicles. One of them WNT seems to be very important. Her talk has very technical but to break it down for everyone, she has found specific pathways in hair growth. Sort of like the krebs cycle if you will. This chemical turns this on… then this happens… and so on and so on. If you inhibit this chemical then this happens.
She is the leading researcher in the molecular biology of hair follicles at the university of Pennsylvania.
Next speaker Dr. Jerry Cooley in the importance of holding solutions in HT.
Graft storage solutions…
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There are no FDA approved solutions.
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The ideal holding solution?
A soluition that supports and protects grafts… Keep them from necrosing or inhibit apoptosis or programmed cell death?
Basic principles… good holding solution may have:
- Good Osmolarity around 310mOsmol/L in humans.
- Ph is very important. needs to be close to physiologic Ph… around 7.3-7.4
- Temperature. Cooling stops sodium and chloride pumps.
- Nutrients glucose, amino acids, vitamins,
- Antioxidants.
Types of Media Storage:
- Saline/plasmalyte A/etc…
- Culture Media
- Tissue holding solutions for organ transplants such as UW or hypothermasol.