Adoptive T-cell therapies in neuroinfectious and neuroinflammatory diseases

Immune dysfunction, spanning pathogenic autoimmunity and impaired host defense, represents a convergent mechanism across neurological autoimmune and inflammatory diseases and opportunistic infections. Despite advances in immunomodulatory and anti-infective therapies, many patients remain treatment-refractory, reflecting limitations of conventional agents. Adoptive T-cell therapies introduce dynamic "living drugs" capable of in vivo expansion, adaptation, and persistence. These promising characteristics have led to a rapid proliferation of preliminary reports and clinical trials in inflammatory and infectious diseases of the nervous system, placing neurologists at the forefront of this evolving therapeutic landscape. In this Update, we advance a disease-centred conceptual framework designed to reposition T-cell-based therapies within neurological practice. Rather than adopting a technology-driven perspective, we organize disorders according to major patterns of immune dysfunction. Immune deficiency predisposing to opportunistic infection and immune dysregulation driving autoimmunity constitute the principal axes of neurological immune pathology. Within the autoimmune spectrum, distinct immunopathological archetypes (autoantibody-mediated, mixed B- and T-cell-driven, and disorders at the interface of inflammation and neurodegeneration) provide a pragmatic structure for therapeutic reasoning. Building on this classification, we delineate how adoptive T-cells (chimeric antigen receptor T-cells, virus-specific T-cells, and regulatory T-cells) may be differentially aligned with underlying disease biology, linking mechanistic insight to clinical strategy.