STUDIES ON TRANSLOCATION OF IMMUNOGLOBULINS ACROSS INTESTINAL EPITHELIUM

We adapted the peroxidase-labeled antibody method to localization of immunoglobulins and the secretory component (SC) in human intestinal mucosa at the light and electron microscopic levels. Modifications of the method included (1) the use of digitonin in the first wash step of tissues fixed in periodate-lysine-paraformaldehyde; (2) double coating of glass slides with gelatin and egg albumin before application of cyostat sections, and (3) inactivation of endogenous peroxidase by periodic acid treatment of cyostat sections. With these improvements, tissue morphology was well preserved; antigenicity of immunoglobulins and SC was retained; penetration of labeled antibodies into cellular compartments was complete; and confusion at the light microscopic level between peroxidase-containing cells and cells stained with peroxidase-labeled antibodies was avoided.