Rat Anti-Human IL-13 Antibody (S-4442)

Interleukin-13 (IL-13) is a pleiotropic cytokine primarily secreted by activated type 2 helper T cells (Th2), group 2 innate lymphoid cells (ILC2s), mast cells, and basophils, playing a central role in regulating inflammatory and immune responses, particularly those associated with allergic reactions and parasitic infections. Structurally homologous to IL-4, IL-13 exerts its biological effects by binding to a heterodimeric receptor complex composed of the IL-4Rα chain and the specific IL-13Rα1 chain, which subsequently activates the JAK-STAT signaling pathway, notably STAT6, to modulate gene expression in target cells such as epithelial cells, fibroblasts, and B cells. Its key physiological functions include inducing class switching to IgE in B cells, stimulating mucus hypersecretion and goblet cell metaplasia in airway epithelium, promoting alternative activation (M2 polarization) of macrophages, and driving tissue fibrosis by enhancing collagen production, making it a critical mediator in the pathogenesis of asthma, atopic dermatitis, and other fibrotic disorders, thereby establishing it as a major therapeutic target for biologics like dupilumab and tralokinumab that aim to block the IL-4/IL-13 signaling axis.