Comparative demonstration of IgE (immunoglobulin E) in the gastric mucosa using monoclonal and polyclonal antibodies

It was the aim of this study to examine by using biopsy material the suitability of polyclonal and monoclonal antibodies against human IgE to support the clinical diagnosis of gastrointestinal allergy by means of morphological methods. A total of 190 gastric biopsies were collected from 56 ambulant patients; 95 specimens were shock-frozen in liquid nitrogen and treated with monoclonal antibodies (D epsilon 1, D epsilon 2); 95 biopsies were fixed in Bouin's solution, embedded in paraffin and treated with a polyclonal antibody. The slide preparations were examined semiquantitatively. The monoclonal (D epsilon 2) and the polyclonal antibody yielded different staining patterns. The polyclonal antibody mainly stained plasmocytes as constituent parts of the inflammatory infiltrate, which was regarded as a secondary phenomenon following the disruption of the mucus barrier. The monoclonal antibody mainly labeled mast cells within the glandular body of the antral and corpus-type mucosa; this finding we regarded as the most important one in the context of allergic reactions. The employment of the two different methods yielded a complete distribution of IgE-containing cells in the gastric mucosa. The immunohistochemical demonstration of IgE is therefore a useful method to support the clinical diagnosis of allergic processes in the gastrointestinal mucosa.