Immunohistochemical study of S-100 protein in the bovine lymph node and spleen.

Immunohistochemistry using anti-bovine S-100 protein serum was examined in the bovine lymph node and spleen. In the lymph node, immunoreactivity was found in endothelial cells of lymph vessels and in endothelial and reticular cells of the sinuses. In the spleen, immunoreactivity was observed in endothelial cells of the trabecular artery, central artery, penicillar artery, sheathed artery, terminal capillary, trabecular vein and lymph vessel. In addition, the follicular dendritic cells in germinal centers both of the lymph node and spleen were stained with S-100 protein. These findings suggest that S-100 protein of the vascular systems may be related to the flow of lymph and blood.