Immunoelectron localization of HLA-DR, HLA-DP, and HLA-DQ antigens on the microvasculature in normal skin

Abstract

Background: Expression of HLA-DP and HLA-DQ antigens on the microvasculature in normal skin is uncertain. Objective and Methods: We investigated expression of HLA-DR, HLA-DP, and HLA-DQ antigens on the microvasculature in normal skin by light and electron microscopic immunohistochemistry. Results: HLA-DP and HLA-DQ antigens were expressed on the microvasculature, but the intensity of positiveness was variable. By immunoelectron microscopy, HLA-DR, HLA-DP, and HLA-DQ antigens were expressed on the endothelial cells of the microvasculature, but not on the pericytes and the smooth muscle cells. The luminal surface of endothelial cells had a stronger expression of these antigens than the abluminal surface. Conclusion: HLA-DR, HLA-DP, and HLA-DQ antigens are expressed on endothelial cells of the microvasculature in normal skin.