CALCITONIN EXPRESSION OF HIGH ENDOTHELIAL VENULES DURING LYMPHOCYTE MIGRATION IN HUMAN PHARYNGEAL TONSIL

Abstract

The migration routes of lymphocytes through high endothelial venules (HEVs) of controland hypertrophic pharyngeal tonsil (HPT) tissue sections were investigated byimmunohistochemistry using the expression of a hormone [calcitonin (CT)] and two calciumdependent endothelial adhesion molecules (E-selectin and P-selectin), as well as electronmicroscopy. A marked increase in CT-specific staining was observed in the endothelial cells ofHEV in the HPT group compared to the control group. Expressions of E-selectin and P-selectinon HEVs of control group were faint, when compared to the strong expression of these selectinson HEVs of HPT. Electron microscopically, we demonstrated that lymphocytes transmigratedthrough HEV and observed the close membranous contact between endothelial cells andlymphocytes during this process. We speculate that increasing CT during inflammation may beimportant for lymphocyte migration through the HEVs via controlling the expression ofE–selectin and P-selectin.