Plenary Speaker Abstracts

Autoimmune diseases (ADs) are characterized by aberrant immune responses against self-antigens, driven by autoreactive T lymphocytes and autoantibodies. Elucidating the complex interplay among these immunological components offers critical insights into the development of innovative therapeutic strategies. Among the diverse spectrum of ADs, rheumatoid arthritis (RA) and multiple sclerosis (MS) are prototypical disorders in which inflammation plays a central role, albeit in distinct anatomical locations. These conditions share common clinical features, including chronicity and a relapsing-remitting disease course that necessitates long-term management. Cytokines such as IL-6, TNF-α, and IL-17 are key mediators of pathogenic inflammation, promoting immune cell activation and tissue damage. In parallel, angiogenic factors—including vascular endothelial growth factor (VEGF) and angiopoietins—contribute to the inflammatory milieu by facilitating neovascularization and leukocyte recruitment. More recently, placental growth factor (PlGF) has emerged as a critical mediator with dual roles in angiogenesis and T cell differentiation, prompting us to designate it as an “angio-lymphokine.” Notably, PlGF directly enhances the survival of synovial fibroblasts and skews T cell differentiation toward a pro-inflammatory Th17 phenotype. While angiogenesis amplifies inflammation by facilitating immune cell infiltration into target tissues, cytokines secreted by effector cells drive the core pathophysiologic mechanisms of ADs. Therapeutic agents targeting these soluble mediators have demonstrated clinical benefit; however, the intricate crosstalk between cytokines, angiogenic factors, and PlGF warrants further investigation, particularly in the context of their synergistic roles in disease pathogenesis. In this regard, we have recently developed novel PlGF inhibitors designed to concurrently suppress angiogenesis and Th17 cell differentiation with minimal adverse effects. These agents hold significant promise as dual-function therapeutics for the treatment of autoimmune and inflammatory disorders, including RA and MS.