Restricted feeding and human intestinal plasma cell development.

Small intestinal mucosa from 129 necropsies and 15 surgical specimens from infants aged from birth to 21 months was examined for the presence of cells containing IgA, IgM, and IgG using the PAP immunoperoxidase technique. Immunoglobulin containing cells were nearly always absent in infants under 1 week of age but occurred in the second week of life in infants who had had milk feeds. At this time, IgM containing cells were predominant, but IgA containing cells were more numerous by the sixth week. IgG containing cells were generally sparse. Parenterally fed infants who had received little or no intestinal milk showed significantly fewer immunoglobulin containing cells than those who had been fed normally, irrespective of gestation. Lack of stimulation by food and bacterial antigens may contribute to immunoglobulin containing cells failing to occur in these parenterally fed neonates.