The SLC4A1 antibody targets the SLC4A1 gene product, also known as anion exchanger 1 (AE1) or Band 3 protein, a critical transmembrane protein expressed in erythrocytes and renal tubular cells. AE1 plays a dual role: in red blood cells, it facilitates chloride-bicarbonate exchange to regulate CO₂ transport and acid-base homeostasis, while in the kidney, it mediates bicarbonate reabsorption in the distal nephron. SLC4A1 antibodies are primarily studied in the context of autoimmune hemolytic anemia (AIHA) and rare inherited disorders. In AIHA, autoantibodies against AE1 disrupt red cell membrane integrity, leading to premature destruction. These antibodies are often detected via the direct antiglobulin test (DAT) and are associated with both warm and cold antibody-mediated AIHA subtypes. Additionally, SLC4A1 mutations underlie hereditary spherocytosis (HS) and distal renal tubular acidosis (dRTA), where altered protein expression may trigger secondary autoimmune responses. Research also explores SLC4A1 antibodies in paroxysmal nocturnal hemoglobinuria (PNH) and transfusion-related complications. Their clinical utility extends to diagnosing erythrocyte membrane disorders and differentiating autoimmune from congenital hemolytic anemias. Understanding SLC4A1 antibody interactions aids in elucidating pathogenic mechanisms and guiding targeted therapies, such as immunosuppression or complement inhibition.