TSPAN32 (tetraspanin 32) is a membrane-localized protein primarily expressed in hematopoietic and immune cells, particularly natural killer cells and CD8+ T cells 1. As a member of the tetraspanin superfamily, TSPAN32 functions as a regulator of immune cell activation and metabolic adaptation 1. The protein is transcriptionally regulated by the TCF3/ID3 axis, with TCF3 serving as a direct transcriptional repressor of TSPAN32 2. TSPAN32 expression is downregulated during T cell and B cell activation, suggesting a role in maintaining lymphocyte homeostasis 1, 3, 4. In disease contexts, TSPAN32 is significantly reduced in multiple autoimmune and malignant conditions. In rheumatoid arthritis, reduced TSPAN32 levels in T cells correlate with inflammatory markers and disease activity, suggesting a protective immunoregulatory function 5. Similarly, TSPAN32 downregulation is observed in systemic lupus erythematosus plasmablasts, modulated by type I interferons 4. In hematologic malignancies, including Burkitt lymphoma and B-cell acute lymphoblastic leukemia, TSPAN32 suppression is associated with disease progression, and lower expression predicts poor overall survival 2, 6. These findings position TSPAN32 as a potential diagnostic and prognostic biomarker for autoimmune and hematopoietic malignancies, with therapeutic implications.