CTLA4 and autoimmune hemolytic anemia: Concerning cellular immunity, autoreactive clonal T- CD8+cells have been reported in about 50% of AIHA cases; moreover, polymorphism of the cytotoxic T-lymphocyte antigen-4 (CTLA-4) gene and of lymphotoxin-α (LT-α) may represent a risk factor for primary or secondary AIHA development (4).