The mechanisms that help with the repigmentaion of the skin for people with Vitiligo are not obvious to the lay person or perhaps some of the medical folks out there. The question has arisen countless times and recently I was chatting with a good friend, Ray Boissy. Ph.D. (Chairman of the NVFI, the National Vitiligo Foundation). It’s serendipitous that the NVFI is based here in Cincinnati where we happen to live. I asked Ray to let me know his thoughts and I was surprised that an answer was forthcoming that I actually understood, well understood as only lay-people can understand the words.
His reply follows:
Repigmentation of vitiligo lesions can occur with UVB treatment. The mechanism underlying this pigmentation response is two-fold.
- UVB Narrowband exposure is mildly immunosuppressive for the skin so that in vitiligo an autoimmune response that may be occurring against the pigment cell could be suppressed and destruction of the pigment cell could be halted or slowed down.
- UVB NB can promote pigment cell development and movement so that in the vitiligo lesion where there is no autoimmune response (either normally or after UVB suppression) stem cells for the pigment cells that reside in the hair follicle will be induced to develop and migrate out of the hair follicle and replace those that were lost in the lesion.
The news in (1) above was really a surprise as we’re often asked “Will UVB Narrowband stop the progress of my Vitiligo?” and now I can say “Perhaps it will!” This is really good news for the Vitiligo sufferer.
Practically speaking we tend to see great succcess with re-pigmentation of the skin in areas where we have hair or hair follicles. The last remaining pigment cells gather in the base of many hair follicles and when repigmentaion begins, perhaps in 40 to 60 treatments (on alternate days) one sees freckling start around a hair follicle and if there are sufficient numbers of hair follicles then as time goes by, the freckles grow and if all is well they merge and fill in an entire lesion. We do find that areas of the body where we have few or no hair follicles then repigmention is a challenge and for some impossible.