Oral mucosal immune system (OALT)

The oral mucosal immune system is a specialized anatomical and functional division of the mucosa-associated lymphoid tissue (MALT) that serves as the primary immunological barrier for the oral cavity. It integrates physical barriers, such as the stratified squamous epithelium, with a complex network of innate and adaptive immune cells, including Langerhans cells, neutrophils, T-cells, and B-cells [1, 16, 19]. A hallmark feature is the production of secretory IgA (sIgA) by plasma cells in salivary glands and local lymphoid tissues, which neutralizes pathogens and maintains tolerance to commensal microbiota [3, 4, 7]. Dysregulation of this system is central to the pathogenesis of a broad range of conditions, from local inflammatory diseases like periodontitis and aphthous stomatitis to systemic autoimmune disorders such as Sjögren's syndrome and pemphigus vulgaris [5, 11, 19]. Therapeutic strategies typically focus on local or systemic immunomodulation using corticosteroids, calcineurin inhibitors, or biological agents to suppress aberrant immune responses and restore homeostasis [9, 10, 15]. Additionally, the oral mucosa is an active site for vaccine development, as it can leverage local lymphoid structures like the tonsils to elicit both mucosal and systemic immunity [4, 12, 14].

Other names

Oral-associated lymphoid tissueOALTOral immune systemOral mucosa-associated lymphoid tissueSalivary immune system

Drugs modulate the oral mucosal immune system by suppressing localized T-cell or B-cell mediated inflammatory responses, inhibiting pro-inflammatory cytokine signaling (e.g., TNF-alpha), or restoring the mucosal barrier and microbial balance through antimicrobial or immunosuppressive activity.