Researchers at Seoul National University Hospital (SNUH) have discovered a method that allows hair loss patients to receive other people's healthy hair without taking an immunosuppressant, the hospital said Thursday.
|Professor Kwon Oh-sang|
Currently, hair loss patients undergo drug therapy in the initial stage. However, if the hair loss progressed to such an extent that it is difficult to treat with drugs, patients consider hair transplantation as an option.
In particular, hair transplantation is the only known treatment for permanent hair loss caused by anticancer drugs or severe androgenetic hair loss.
The current hair transplant is called autologous hair transplantation, which grafts a piece of the patient’s skin that contains healthy hair follicles and transplants it in the area where hair loss has occurred. However, this method only utilizes the patient’s remaining hair follicles and does not generate any new hair follicles.
To solve such problems, the team, led by Professor Kwon Oh-sang of the department of dermatology at the hospital, focused on dendritic cells involved in human immunity.
Dendritic cells recognize the abnormal cells such as tumors in the human body and then play a role in ordering immune T-cells to attack the tumors, while it also attacks transplanted organs after recognizing them as a foreign body or germ.
The researchers focused on the fact that the donor dendritic cells play an important role in acute immune rejection.
The team used ultraviolet B irradiation, which is widely used in dermatologic therapies, to remove all of the donor dendritic cells present in the donor hair follicles.
Afterward, the researchers performed an allogeneic hair graft on 24 humanized mice, which had the same level of the immune system as the human, through the hematopoietic stem cell transplantation.
As a result, the transplanted hair follicles produced new black hair, and the hair was found to survive longer than six months without an immune rejection response.
According to the team, hair follicles are independent organs present in the skin and have an “immune privilege” that is relatively free from immune rejection. As the brain and cornea also have this privilege, the team could reproduce the same state of hair follicles that existed in people’s bodies by removing the donor dendritic cells involved in direct antigen presentation.
"Through this research, we have obtained a new medical basis for hair transplantation without the use of immunosuppressant," Professor Kwon said. "Although it would be a challenge to apply it to clinical practice, the research is meaningful as it can utilize new implantable resources that were not possible before.”