IgG subclass-containing cells around the lymph follicle in the human intestine.

The authors previously reported the ring-like distribution of IgG-containing cells around the lymph follicle in both the small and large intestine. In the present study, the distribution of IgG subclass-containing cells around the lymph follicle was examined in both the small and large intestine, including Peyer's patches, by the indirect immunoperoxidase staining method. A ring-like distribution of IgG subclass-containing cells was observed in 14 out of 21 lymph follicles including 4 Peyer's patches (66.7%) in the terminal ileum, and 4 out of 7 (57.1%) in the large intestine. The percentages of IgG1-, IgG2-, IgG3-, and IgG4- containing cells around the lymph follicle in the terminal ileum were 27.6 +/- 11.6%, 51.9 +/- 15.4%, 16.5 +/- 10.2%, and 4.0 +/- 3.1%, respectively, and those in the large intestine were 22.9 +/- 15.4%, 47.4 +/- 14.9%, 11.2 +/- 4.1%, and 18.5 +/- 7.7%, respectively. Thus, among the IgG subclasses, IgG2-containing cells showed the most frequent ring-like distribution around the lymph follicle. The IgG2 predominance around the lymph follicle in the intestine was markedly different from reported IgG1 predominance in the lamina propria in the large intestine. This difference in IgG subclass distribution may suggest different origins of the IgG subclass-containing cells in the lamina propria and in areas around the lymph follicle.