[Inhibitory effect of bispecific antibody targeting IL-12 p40 and TNF-α simultaneously on psoriasis in mice].

Objective To construct bispecific antibodies, which can block interleukin 12 (IL-12)/IL-23 p40 subunit and tumor necrosis factor α (TNF-α) simultaneously, and identify their biological function and inhibitory effect on psoriasis formation in mice. Methods Based on the sequences of adalimumab and ustekinumab, three kinds of bispecific antibodies were designed, named BiAU003, BiAU022 and BiAU023. The specificity and binding capacity of bispecific antibodies were determined by ELISA. After co-treated with bispecific antibodies and TNF-α, the level of endothelial leukocyte adhesion molecule-1 (ELMA-1) labeled with fluorescein isothiocyanate (FITC) in human umbilical vein endothelial cells (HUVECs) were examined by flow cytometry. Human peripheral blood mononuclear cells (PBMCs) were purified and cultured in the medium containing IL-2 and IL-12 in the absence or presence of bispecific antibodies. Commercial ELISA kit was used to detect interferon γ (IFN-γ) concentration in the supernatant. BALB/c mice were used for psoriasis model construction through injection of IL-12 and TNF-α subcutaneously. Then they were treated with the bispecific antibodies. Psoriasic skin was measured in thickness and scale under microscopy after H&E staining. Results The three kinds of bispecific antibodies could specifically recognize IL-12/23 p40 and TNF-α protein, and inhibit IFN-γ secretion and the expression of ELAM-1 protein. Data also indicated that bispecific antibodies inhibited the formation of psoriasic skin, and showed an equal or superior effect to control antibody drug. Conclusion The novel bispecific antibodies, BiAU003, BiAU022 and BiAU023, can serve as an antagonist of TNF-α and IL-12/23 p40, and have a blocking effect on mouse psoriasis formation.