Survival of Oral Human Immune Serum Globulin in the Gastrointestinal Tract of Low Birth Weight Infants

Abstract
Summary: Six immature infants were given oral feedings of 10% preservative-free human immune serum globulin ranging from 1 to 8 ml/kg/day. A seventh infant served as a control. Undigested and partially digested IgG was detected in the stools in significant quantities in all but the control infant. This coproantibody retained significant opsonic activity for type III group B streptococci as determined by a chemiluminescence assay, but lost most of its tetanus antibody activity. The newborn infants' enzymatic immaturity or rapid transit time permits the passage of intact IgG or partially digested IgG to pass throughout the gastrointestinal tract. Speculation: The survival of intact IgG immunoglobulin in the stool of newborns after its oral administration may indicate that specific IgG antibody can serve as a colostral IgA substitute. Oral immunoglobulin may be of value in the prevention or treatment of enteric infections (e.g., Escherichia coli, V. cholera, S. typhosa, rotavirus) or intoxications (e.g., infantile botulism).