Dr. Claire Higgins and her colleague Dr. Colin Jahoda have published an overview of hair cloning and the challenges scientists face in attempting to develop hair regeneration therapies for androgenetic alopecia or common balding. The article, published in Hair Transplant Forum International, points to two central problems in developing a hair loss therapy. The first is the difficulty in getting dermal papilla cells in humans to self-aggregate and form hair follicles and the second is the inability, thus far, of scientists to generate normal hairs and follicles.
Higgins and Jahoda describe how it has been known for decades, through the work of Lille and Wang and others, that rat dermal papillae self-organize into new hair-producing follicles when they are injected or grafted into the skin. Human dermal papilla cells, on the other hand, have never exhibited what they call the “aggregation phenomena,” and instead they disperse in the skin in what appears to be a wound healing mechanism. In fact, human papillae, when grown in a laboratory culture, can act as “mesenchymal stem cells” and differentiate into a variety of cell types.
While multiple efforts to induce dermal papillae to form new hair follicles have failed, the research that Higgins and Jahoda have published on hair follicle neogenesis has resulted in a new technique to do just that. The success of the 3-D culturing of dermal papillae to induce hair follicle neogenesis was a breakthrough in that the scientists have found a way to improve the intercellular communication that is essential to inducing follicle growth.
Having made significant progress in improving this vital communication link between dermal papillae cells, scientists still have to contend with a series of obstacles that stand in the way of a hair cloning therapy for human hair loss. One such problem is the quality of hairs that they have been able to grow using the hair follicle neogenesis technique. The hairs they have successfully produced have been small and have grown in non-uniform direction. Another unanswered issue is how long the hair follicles will grow and whether or not they exhibit the cyclical hair follicle growth patterns of a typical human hair follicle. The ability to reproduce significant quantities of normal hair will continue to be the central focus of research going forward.