IgA is the most abundant immunoglobulin in body fluids and the second most abundant immunoglobulin in plasma, found at a concentration of 0.4 to 2.2 mg/ml. It plays a very important role in the first specific defense against natural infection. Secretory IgA differs from serum IgA in that it contains two additional peptides: the secretory component and the J chain. Prepared from plasma shown to be non reactive for HbsAG, anti-HCV, anti-HBc, and negative for anti-HIV 1 & 2 by FDA approved tests. >95percent pure by SDS-PAGE.