Ameliorative effects of Toxocara canis recombinant C-type lectin on atopic dermatitis in a mouse model

Atopic dermatitis (AD) is a chronic inflammatory skin disease marked by severe itching and eczematous lesions, primarily driven by immune system dysregulation. Current treatments largely focus on symptom relief rather than addressing underlying immune dysfunction. The parasitic nematode Toxocara canis secretes excretory-secretory proteins, among which C-type lectin (CTL) has notable immunomodulatory properties that may offer a novel therapeutic approach for AD.

We sought to evaluate the therapeutic potential of T canis recombinant CTL (rCTL) in a BALB/c mouse model of AD.

Thirty-five mice were divided into 7 groups; all except from the normal control group were sensitized and challenged with 2,4-dinitrochlorobenzene to induce AD-like symptoms. Treatment groups received rCTL, topical or injected dexamethasone, or bacterial lysate. The prevention group was pretreated with rCTL (subcutaneously and intraperitoneally) before 2,4-dinitrochlorobenzene exposure. Dermatitis severity was assessed biweekly, and pruritus was quantified through blinded video analysis of scratching behavior. Serum IgE levels were measured via ELISA, and histopathologic analyses examined epidermal and dermal changes.

T canis rCTL significantly reduced dermatitis severity, pruritic behavior, and serum IgE compared with controls, including in dexamethasone-treated groups (P < .05). Histology revealed reduced epidermal thickening and decreased inflammatory cell infiltration in rCTL-treated mice, indicating effective suppression of allergic inflammation. The prevention achieved by rCTL was modest and not highly effective.

T canis rCTL shows promising immunomodulatory effects, improving both clinical and histopathologic features of AD in mice. These findings highlight rCTL's potential as a novel immunotherapeutic agent, warranting further mechanistic and long-term studies to confirm clinical applicability.