Lymphopoiesis of the Oral Mucosa

Abstract

Comparison of the cytology of normal lymph nodes and lymphoid tissue in human oral mucosa shows similar basic structure. Germinal centers contain reticulum cells and immature lymphocytes showing mitotic activity and RNA synthesis. The mature lymphocytes are found in the periphery of the germinal center. The germinal center cells are PAS positive showing the presence of neutral mucopolysaccharides. They are negative for acid mucopolysaccharides. Silver impregnation shows sparse argyophilic fibers in the germinal center and periphery. The ground substance of the lymphoid tissue does not stain positively, either for neutral or acid mucopolysaccharides. Capillaries are found in the germinal center. The nuclear volume of mature lymphocytes varies widely and is not useful criteria. The lymphoid tissue arises in the oral mucosa in cases of irritation from oral prosthesis. The perivascular undifferentiated mesenchymal cells proliferate and differentiate into reticulum cells and lymphocytes, which organize into lymphoid tissue architecture.