5-AZACYTIDINE TREATMENT INDUCES AUTOIMMUNE VITILIGO IN PARENTAL CONTROL STRAINS OF THE SMYTH LINE CHICKEN MODEL FOR AUTOIMMUNE VITILIGO

The effect of 5-Azacytidine (5-AzaC) on melanization was examined in t wo sublines of the Smyth line (SL) chicken model for autoimmune vitili go, in two MHC-matched vitiligo-susceptible but normally pigmented con trols (BL), and in nonsusceptible controls (LBL). 5-AzaC was administe red ip every 3 days from day of hatch to 18 weeks at levels of 1 or 3 mg/kg body wt, Both treatments increased (P < 0.01) the incidence of a utoimmune vitiligo in BL controls. In contrast, treatment significantl y depressed (P < 0.01) the expected high incidence of vitiligo in one SL subline, but not in the other. There were no apparent pigmentation changes in 5-AzaG-treated LBL controls. 5-AzaC had dose-dependent depr essing effects (P < 0.01) on body and lymphoid organ weights. Histolog ical and mitogen assay data suggest negative effects on lymphocyte num ber and function. The data show that 5-AzaC can initiate autoimmune di sease in genetically susceptible but phenotypically normal individuals . (C) 1996 Academic Press, Inc.