Antibodies in Milk Directed Against Specific Enteropathogens

Abstract

Many organisms have been identified as causing diarrhea in infants and children (1). Diarrhea is prevalent when personal hygiene and sanitation are deficient. In addition diarrhea occurs more frequently in infants who are formula fed compared to those who are bottle fed (2–4). Human milk provides a large number of nonspecific and specific Table 1. Enteropathogens against which antibodies have been reported in human colostrum and milk. protective factors that are present in varying concentrations throughout all stages of lactation (5,6). Total secretory IgA immunoglobulin and specific IgA antibodies to many enteropathogens have been recognized in human milk (table 1) (7,8). Secretory IgA is not absorbed in significant quantity from the human intestine and therefore presumably acts at the mucosal surface of the intestine (8). Secretory IgA is more resistant to acid degradation and to the proteolytic activity of gut enzymes than is serum IgA, and can be found intact in significant quantities in feces (9). It is known that immunoglobulin concentrations and antibody titers are high in colostrum and decrease significantly in mature milk. Little is known about the relation between the presence and concentration of these antibodies and the occurrence of diarrhea due to various enteropathogens.