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 K(d), D/L(dm7), I-A(k) and I-E(k) in the atopic dermatitis (AD) mouse model NC/Nga as “H-2(nc).” 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-2(nc) or H-2(b), respectively, in addition to the NC/Nga genetic background.