IgA is one of the most abundant antibody isotypes produced in the body. It is mainly secreted by plasma cells located in the lamina propria. There are two subtypes of IgA, IgA1 and IgA2 present primarily in the airways and colon, respectively.

IgA from human serum has been used in enzyme-linked immunosorbent assay (ELISA) for anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-spike-receptor binding domain (RBD) antibody detection in blood samples.

Purified human IgA may be used to study its physiological and biological effects on processes such as inflammation, pathogen elimination, regulation of antibody-dependent-cell-mediated cytotoxicity (ADCC), modulation of phagocytosis, degranulation of eosinophils and basophils and modulation of respiratory burst activity.

IgA aids in inducing a defense mechanism against various viral pathogens such as rotavirus, poliovirus, influenza virus, and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It regulates excessive immune responses in inflammatory diseases. IgA also has the potential to trigger neutrophil recruitment for cell killing.

Solution in 0.01 M Phosphate Buffer saline, pH 7.4, containing 15 mM sodium azide as a preservative.