An anti-cell adhesion molecule 1 antibody improves mite antigen-induced atopic dermatitis-like lesions and pruritus in NC/Nga mice

OBJECTIVE: In atopic dermatitis, skin scratching leads to worsening of the dermatitis. Cell adhesion molecule 1 (CADM1), an immunoglobulin superfamily member, is highly expressed in peripheral nerve fibers, and the anti-CADM1 antibody 3E1 preferentially localizes to dermal nerve fibers upon subcutaneous injection and exerts analgesic effects. Whether 3E1 improves atopic dermatitis-like lesions and pruritus was examined in NC/Nga mice. SUBJECTS AND METHODS: The systemic distribution of 3E1 after intravenous injection was examined using indocyanine green imaging, immunostaining, and Western blotting techniques. Atopic dermatitis-like lesions were created by repeated application of the mite antigen Biostir. 3E1 was then administered subcutaneously at the lesion sites (30 μg/day; 3 consecutive days) or intravenously via the tail vein (5 mg/kg; 3 times every other day), and macroscopic inflammatory signs of the skin, such as erythema and crust formation, were recorded. Mice were videotaped, and the duration of skin scratching behavior was measured. RESULTS: Intravenously injected 3E1 accumulated in dermal nerve fibers and dorsal root ganglia. By both routes of administration, the 3E1-treated group showed a shorter duration of scratching behavior in the first week and a faster improvement in dermatitis in the second week after the initial injection than the control group. CONCLUSION: 3E1 has potential as a therapeutic agent for atopic dermatitis owing to its antipruritic effect.