Immunoglobulin A (IgA)

Immunoglobulins are proteins produced by plasma cells, a type of white blood cells and are an important part of your defense system. There are 5 types of immunoglobulins namely IgG, IgM, IgA, IgE & IgD. Immunoglobulin IgA is mainly present in the mucosal lining of stomach, intestines & lungs and protects from invasion by germs. It is of 2 types namely IgA1 & IgA2 of which IgA1 is predominant. IgA2 is found in milk secretions. High levels of IgA are seen in chronic infections, liver disease, allergy, Lupus, Sarcoidosis & IgA gammopathy. Low levels of IgA are usually due to congenital deficiency.