Lamina propria macrophages of intestine of the guinea pig. Possible role in phagocytosis of migrating cells.
The macrophages of lamina propria were commonly found both in the small and the large intestine of guinea pigs, mice, rats, and in human duodenum. The frequency of macrophage occurrence was highest in the lamina propria of villous apices of the small intestine and beneath the lining epithelium of the large intestine. In the cytoplasm of lamina propria macrophages localized in those regions, Feulgen-positive (DNA-containing) granules could be observed particularly in the guinea pig intestine. Autoradiography of the latter, 3 to 5 days after [3H]thymidine injection, showed the coincidence of occurrence of labeled Feulgen-positive granules in the macrophage cytoplasm with the appearance of labeled epithelial cells and sheath-fibroblasts in the region of lamina propria containing the highest accumulation of macrophages, i.e., at the apices of villi of the small intestine and beneath the lining epithelium of the large intestine. Labeled nuclei of macrophages were observed scarcely and much less frequently than were labeled cytoplasmic granules. No labeled Feulgen-positive granules could be seen in macrophages 1/2 hr, 1, 2, and 7 days after [3H]thymidine injection. It is suggested that the lamina propria macrophages may play a role in the phagocytosis of some migrating cells of the intestinal mucosa, most probably of the sheath-fibroblasts and/or intraepithelial lymphocytes.
D000818:Animals; D001345:Autoradiography; D002465:Cell Movement; D006168:Guinea Pigs; D006801:Humans; D007082:Ileum / Q000166:cytology / Q000201:enzymology; D007413:Intestinal Mucosa / Q000166:cytology* / Q000201:enzymology; D007420:Intestine, Large / Q000166:cytology* / Q000201:enzymology; D007421:Intestine, Small / Q000166:cytology* / Q000201:enzymology; D051379:Mice; D010587:Phagocytosis; D051381:Rats; D013045:Species Specificity