Mechanisms of Interleukin-10-Mediated Immunosuppression in Viral Infections

Interleukin-10 (IL-10), a potent anti-inflammatory cytokine, plays a vital role in regulating immune responses across various infectious and inflammatory conditions. While IL-10 is essential for preventing excessive tissue damage and maintaining immune homeostasis (e.g., respiratory syncytial virus), its elevated levels could result in immunosuppression during viral infections, enabling viruses to evade host defenses (e.g., foot-and-mouth disease virus). This review aims to elucidate the mechanisms through which IL-10 mediates immunosuppression in viral infections and to explore the implications of these mechanisms for therapeutic intervention. The key scientific concepts outlined in this review include the mechanisms of IL-10 production and its varied impacts on the immune response during viral infections. Specifically, we discuss the multifaceted inhibitory effects of IL-10 on innate and adaptive immunity, including its implications for antigen presentation, T cells activation, pro-inflammatory cytokine production, immune cell differentiation, trafficking, apoptosis, and co-inhibitory expression related to T cells exhaustion. Finally, we discuss the therapeutic potential of targeting IL-10, such as monoclonal antibodies and small molecule inhibitors, and their potential to restore effective immune responses. By summarizing current knowledge on IL-10's role in viral infections, this review offers a thorough insight into its immunosuppressive mechanisms and their therapeutic potential, paving the way for innovative treatment strategies in viral diseases.