Ring-like distribution of IgG-containing cells around the lymph follicle in the human intestine.

Immunoglobulin (Ig)-containing cells were studied in the lamina propria of the normal human large bowel and around the lymph follicle, including Peyer's patches, in the normal intestine. Ig-containing cells were identified by the indirect immunoperoxidase staining method, using mouse anti-human Ig monoclonal antibodies. In the lamina propria in the large bowel, the mean percentage of IgA+ (IgA1+ cells and IgA2+ cells), IgM+, IgD+, IgG+ and IgE+ cells was 75.9, 8.5, 7.3, 5.8, 2.5, respectively (total 100), namely there was a marked preponderance of IgA+ cells in comparison to IgG+ cells. However, IgG+ cells were observed not only on the epithelial but also in the serosal side of lymph follicles, showing a ring-like pattern. Ig+ cells of the other four classes did not show such a pattern. The ring-like distribution of IgG+ cells around lymph follicles was observed in both the large and small intestine including Peyer's patches. This tendency was observed in 9 out of 14 follicles (64.3 per cent). A large number of IgG+ cells were observed outside lymph follicles, while a small number of IgG+ cells were observed at the most outer rim of lymph follicles which suggested a local maturation of IgG+ cells. The significance and the role of the newly recognized IgG+ cells in the vicinity of lymph follicles remain to be resolved.