Hanson L A, Brinton C, Carlsson B, Dahlgren U, Mellander L, Sutton A, Söderström T
Acta Paediatr Scand Suppl. 1982;296:53-5. doi: 10.1111/j.1651-2227.1982.tb09596.x.
Human infants are relatively deficient in the IgA system defending mucosal membranes, but are provided via the maternal milk with considerable amounts of SIgA directed against microbes and food antigens to which both mother and infant are exposed. It is possible that serum antibodies may support the mucosal defense as do the lactoferrin, lysozyme and other defense factors present in the milk.