Mechanistic studies indicate that APS, via activation of the TLR4 signaling pathway, induces the secretion of Th1-polarizing cytokines (e.g., IL-12) alongside Th2-type cytokines (e.g., IL-4), facilitating a balanced Th1/Th2 hybrid immune response (172). The gene discussed is TLR4; the disease is autoimmune polyendocrinopathy.