Secretory immunoglobulin A (SIgA) is a type of antibody that is produced in mucosal areas of the body, such as the intestines, respiratory tract, and genitourinary tract. It plays a crucial role in protecting these mucosal surfaces from infections by binding to pathogens and preventing them from attaching to the mucosal cells. SIgA is also involved in neutralizing toxins and allergens, and promoting the elimination of pathogens through mechanisms such as agglutination and immune exclusion.
