Mucosal Microhernias in the Nonhuman Primate Colon: Their Role in the Pathogenesis of Colonic Disease

Microhernias of colonic mucosal glands through the muscularis mucosae are common in human and nonhuman primate colons, and are related to submucosal lymphoid nodules. In nonhuman primates they have been shown to play an important role in the spread of inflammatory diseases from the lamina propria to the submucosa by allowing the infective agents to pass through the muscularis mucosae. The lymphoid tissue of the alimentary tract is composed predominantly of B lymphocytes and produces humoral antibodies. This property of the lymphoid component of these microhernias may thus play a significant role in determining which infective colonic diseases penetrate into the submucosa and which remain largely confined to the lamina propria.