A New Method for Growing Hair

Hair loss can be a result of natural aging or can be due to a variety of pathological conditions. Male pattern hair loss, for example, is a generally progressive and permanent process.  On the other hand, hair loss caused by iron or thyroid hormone deficiency can be cured by the replenishment of iron and thyroid hormones, which may lead to normal hair growth again.

Popular methods to prevent the loss of hair include medication and hair transplants. While these options do slow down the hair loss process and stimulate the growth of existing hairs, they are not a permanent panacea or “cure” for baldness. Transplants may also be quite costly, ranging anywhere from $4,000 - $15,000. So is there any hope for the population that is fraught with insecurities from their lack of lush locks? Recent scientific discovery has proven that yes, there indeed may be a way to grow new hair, not simply redistribute it. 

Human vs. rodent papillae papillae

This relatively new finding is actually not based on a completely novel idea. Dermal papillae, cells that form the follicles necessary for hair growth, were known by researchers to contain regenerative properties for over 40 years. Harvested rodent papilla cells, when cultured in a lab then transplanted back onto rodent skin, successfully grew new hairs. However, human papilla cells experienced no such luck. Every time these cells were cultured in a lab, they seemed to lose their power to generate hair follicles. Instead, they “revert to basic skin cells”, as noted by Colin Jahoda, PhD, professor of stem cell sciences at Durham University, who is a co-study leader of this joint research effort alongside Angela Christiano, PhD, a Richard and Mildred Rhodebeck Professor of Dermatology and Professor of Genetics & Development at Columbia University Medical Center (CUMC).

Changing the Game

Though both rodent and human papilla cells were grown in culture, the starkly contrasting outcomes had left researchers stumped. That is, until they observed a key difference in how the two cells regenerate. Researchers noticed that rodent papilla spontaneously aggregated and formed clumps. This aggregation allowed papillae to interact and send signals that will “reprogram” the recipient skin to generate hair follicles. Human papilla on the other hand, failed to achieve this spontaneous aggregation in two-dimensional tissue culture, meaning no follicles can be formed. Therefore, researchers attempted a new technique of growing human papilla cells that will also result in aggregation of those cells. This new technique involved adding 3000 papilla cells onto the lid of a petri dish, and then flipping the lid over so the cells will be cultured in hanging drops.

Applying the technique

Researchers harvested dermal papillae from seven human donors and cloned them in tissue culture by applying the new technique. The cultured papillae were then transplanted onto human skin grafted onto mice. The skin used was not just any skin; it was the foreskin of circumcised infants, which is virtually hairless. Researchers supposed that if the newly cultured cells are able to grow hair on infant foreskin, than the cells will have a high possibility of growing hair on the scalp as well. The method was a success. Five out of the seven human papilla cells that were transplanted led to new hair growth that lasted around six weeks. DNA testing confirmed that the new hair follicles genetically matched those of the donors.

Conclusion

As of now, the method is still in its early stages. Researchers contend that more work needs to be done before it can be properly implemented on humans. For one thing, researchers are not sure what exactly induces the intrinsic properties of hair such as color, angle, positioning, and texture. Further, the way host epidermal cells interact with the implemented papilla cells to create new follicles is not clearly established. Despite all these trials, researchers are generally optimistic that this breakthrough finding holds great potential for the future. Dr. Christiano believes that this new method will be much more efficient in providing patients with new hair follicles, not simply redistribute hair from other parts of the scalp. Current cosmetic procedures and medication do not help much with severe hair loss caused by male pattern baldness. However, once further study is conducted and the new method can be safely applied to humans, researchers are confident that it will treat hair loss far more effectively than existing techniques.