Immunoglobulin A (IgA) is a class of antibody crucial for immune function, predominantly found in mucous secretions like saliva, tears, and gastrointestinal fluids. It acts as a primary defense against pathogens entering the body through these surfaces. There are two main subclasses: IgA1 and IgA2, each contributing to localized immunity. A total IgA test measures the overall concentration of this antibody in the blood, providing insight into the body's general mucosal immune status and its ability to defend against common infections.
Total IgA
Mucosal immunity.