Endocytic stripping of ligands from migrant lymphocytes in high endothelial venules (HEV): implications for immunomodulation vs viral pathogenesis.

Abstract

“Grooming ” of membrane detritis from lymphocyte surfaces by mononuclear phagocytes during migration through lymphatic tissues was proposed as a cause of differences in the potency of comparable populations of lymphocytes to produce the normal lymphocyte transfer reaction (LTR) when equivalent numbers of T cells from blood, afferent lymph, and efferent lymph were injected SC1. Three- to five-fold greater LTR activity was found with efferent lymph cells compared to blood or afferent lymph cells. It is possible that these differences in reactivity were due to anti-idiotypic antibodies or other “blocking factors ” occupying lymphocyte receptors. Isotypic, allotypic and idiotypic immunoregulation occurs in mice, rats, rabbits, and man2•5. The present studies employ light and electron microscopy, cytochemistry and immunochemistry to analyze the endocytic potential of Lewis Rat HEV endothelium toward both particulates and toward autologous lymphocytes whose surfaces have been modified by liganding. Results indicate that HEV endothelial cells nonspecifically remove receptor-blocking proteins during blood to tissue transit.KeywordsAlcian BlueHigh Endothelial VenuleMigrate LymphocyteLymphocyte SurfaceThoracic Duct LymphThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.