Antibody Production to Milk Proteins in the Jejunal Mucosa of Children with Cow's Milk Protein Intolerance

Abstract

Summary: A direct immunofluorescent technique with fluorescein-labeled antigens was used to examine the jejunal mucosa for specific antibody production in 23 children aged 2–25 months referred for diagnostic biopsy. Plasma cells containing antibodies to β-lactoglobulin (βLG) or bovine serum albumin (BSA) were present in 11 of 16 biopsies from patients with cow's milk protein intolerance (CMPI) but only one of eight controls, all on a diet containing cow's milk. Antibody-containing cells (ACC) constituted approximately 0.5–5% of the total (IgA + IgM) plasma cell population. Their presence did not correlate with either histologic abnormality or IgA plasma cell count. Double immunofluorescence with rhodamine-labeled antigens and fluorescein-labeled class-specific anti-human immunoglobulin sera showed the ACC to be approximately 70% IgA cells and 30% IgE cells.