Signs of atopic dermatitis and contact dermatitis affected by distinct H2-haplotype in the NC/Nga genetic background.

We recently advocated in favour of naming a novel H2-haplotype consisting of Kd, D/Ldm7, I-Ak and I-Ek in the atopic dermatitis (AD) mouse model NC/Nga as "H-2nc." The role of the H2-haplotype in AD development was investigated in H2 b -congenic NC/Nga mice (NC.h2 b/b and NC.h2 b/nc ) established by backcrossing. A severe 2,4-dinitrofluorobenzene (DNFB)-induced dermatitis in NC/Nga was alleviated partially in NC.h2 b/nc and significantly in NC.h2 b/b . The AD phenotype was correlated with thymic stromal lymphopoietin (TSLP)-epidermal expression levels and serum levels of total IgE and IL-18/IL-33. Histologically, allergic contact dermatitis (ACD) was accompanied by lymphocytes and plasma cells-infiltrating perivasculitis in NC.h2 b/nc and NC.h2 b/b and clearly differed from AD accompanied by neutrophils, eosinophils and macrophages-infiltrating diffuse suppurative dermatitis in NC/Nga. Interestingly, IFN-γ/IL-17 production from autoreactive CD4+ T-cells remarkably increased in DNFB-sensitised NC.h2 b/b but not in NC/Nga. Our findings suggest that AD or ACD may depend on haplotype H-2nc or H-2b, respectively, in addition to the NC/Nga genetic background.