GROWTH-FACTOR MESSENGER-RNA LEVELS IN ALOPECIA-AREATA BEFORE AND AFTER TREATMENT WITH THE CONTACT ALLERGEN DIPHENYLCYCLOPROPENONE

The early immune response in alopecia areata is characterized by a Th1 T helper cell cytokine pattern and an aberrant expression of ICAM-1 a nd HLA-DR molecules on lesional hair bulbs. A counteracting cytokine p attern induced by a therapeutic contact dermatitis is supposed to medi ate the hair regrowth. In addition to cytokines, growth factors have b een shown to influence immune responses, and we therefore investigated the expression levels for a panel of growth factors in untreated vers us alopecia areata after treatment with the contact sensitizer dipheny lcyclopropenone. Using semiquantitative reverse-transcriptase polymera se chain reaction we detected a striking overexpression of transformin g growth factor beta 1 mRNA in successfully treated patients. This cyt okine has been shown to be a potent immune response modifier, which ca n suppress Th1 immune responses. The way in which topical immunotherap y induces hair regrowth in alopecia areata is unknown, but a lesional increased expression of transforming growth factor beta 1 may be a pos sible mechanism.