What is it going to take to clone hair, and how will such a technology help you?
Cloning is the latest craze in the world of science and biotechnology these days, and if you’ve been following the news at all, you’ll know that many major decisions are being made by those in power as to what limits are going to be set on this technology in the coming years. Scientists from countries outside the United States are vowing to begin work cloning humans within the year, and everything from specific organs to complete organisms are on the agenda.
What good is that going to do your balding head, you may ask? Needless to say, this is an exciting time, and the concept of cloning a hair follicle is the focus of many researchers as well. The general concept behind follicle cloning has its roots in traditional hair transplantation procedures.
Many of you are working hard with the proven treatments to maintain and regrow a little bit of hair. We all pretty much know that transplants are a last resort due to their high cost and sometimes high risk and safety issues. In addition to these concerns however are the issue of donor area availability.
Currently, transplant physicians take a section of hair from the back of the head (containing follicles which do not succumb to the onslaught of DHT) and cut a strip of skin off the person’s head.
That hair-covered strip of skin is then used as the donor area, and the follicles found on it are transplanted from the strip to the front of the person’s scalp, where they are missing hair.
Needless to say scalping is not the most enjoyable experience, and the amount of hair is extremely limited which is probably why many hair transplants cannot provide the hair density most would desire.
Enter, hair cloning. The idea with hair cloning is quite simple: An unlimited amount of donor hair. The ramifications of this are huge. First, there will not need to be any major surgery involving the removal of scalp from the person’s head. Second, the density issue will only be limited by the technology used to implant the follicles into the front of the scalp.
Currently, there are limitations on the amount of “trauma” the scalp can endure when new follicles are placed into it, and it is no small task dealing with post-transplant ingrown hairs, infections, and other skin related problems. Either way, the amount of available hair will no longer be limited, and the density issue may become a thing of the past.
In the light of the rapidly developing hair stem cell research going on in the medical community today, making use of these same cells for producing new tissue or even whole organs is proving to be very challenging. Cloning of a hair follicle, an elegant miniature organ, is the ultimate task for many scientists and doctors world wide.
The Hair follicle is a result of a long evolution process that is recapitulated every time during skin development in mammals, including human beings.
Skin is composed of 2 principal components: The Epithelial [epidermis] and the Mesenchimal [dermis]. The hair follicle is the final result of a complex interaction between these 2 tissues.
One can not begin to comprehend the complexity of molecular signaling between the cells which interact to form a hair. In fact, scientists are still far from disclosing all the mechanisms governing hair follicle development and the subsequent cyclical life cycle of a hair. Yet, tremendous progress has been made in recent years and our understanding of hair biology has greatly improved. This makes the alluring dream of hair cloning more of a reality.
Ultimately, cloning of hair follicles will most likely have to create follicles which can at least closely emulate the developmental events of a normal follicle which take place during embryo genesis. Therefore, the appropriate cells have to be utilized for this process. No doubt, the principle cell types involved will be:
Stem cells of epidermal origin. Stem cells, by definition, have unlimited capacity to divide and can produce offspring that can differentiate into several cell types.
Dermal cells, of hair follicle origin (dermal papilla or/and dermal sheath), that can issue hair specific signals, to instruct stem cell development.
Within the family of stem cells, there are the following types:
Our understanding of hair stem cell biology greatly improved recently. Several molecular markers of these cells are already known, which enables scientists to identify these cells by using specific tools [antibodies against these markers, for example]. After being “highlighted” in this way, the “pure population” of bulge stem cells can be isolated from the rest of skin cell types. This can now also be done with the Dermal Papilla and Dermal Sheath of the follicle using the same methods. Having these 2 principal cell types isolated in this fashion, scientists can begin attempting to clone hair. One of the great advantages of this “pure cell culture” is that they can be appropriately genetically modified. Specific genes can be introduced into these cells, so that they can correct several pathological conditions on a molecular level. One of them is AGA (also known as Male Pattern Baldness).
Before one can successfully clone hair follicles, one has to understand all the complexities of the follicle, and that the final product of its activity, hair fiber, has many characteristics in and of itself. Therefore, just cloning the follicle isn’t the whole equation. It’s only the beginning. An additional complication involved is the need for the cloned follicle to also have the ability to PRODUCE new hair fibers which have similar characteristics to the original hair follicles. This can be even more difficult task than cloning a hair follicle per se. Eventually, experimentally new hair induction was shown in mid-70 and numerous, more recent experiments confirmed this finding. To successfully clone a hair follicle, several questions must first be answered. Some of them are:
How will we program the stem cells with the appropriate positional information so that cloned hair follicles will have the proper location in skin, symmetry, growth direction, and angle?
How will we program in the exact same pigmentation, so that the cloned hair will be identical in color and will not stand out if placed next to uncloned hair, when viewed from a distance?
Pigmentation of hair is dependent upon the activity and location of the melanocytes, which is another cell type. Do we have to add these cells to the “hair cloning kit”?
Will sebaceous glands also be produced as a result of hair cloning? Sebaceous gland cells also originate from bulge stem cells, but it is not clear at this time which of these mesenchime cells control this process. They are not the same as dermal papillae cells. Obviously, they are cells of the upper part of the dermal sheath. Should these cells also be included into “hair cloning kit”?
If cloned, will there be new follicles cycling in normal fashion? It is believed that it is most likely the Derma Papilla which plays the main role in hair cycling, but in fact, it is not currently known which specific molecules are in control of this process.