Microanatomy of lymphocyte-endothelial interactions at the high endothelial venules of lymph nodes.
Lymphocyte trafficking into lymph nodes and Peyer's patches is mediated primarily by specifically differentiated venules, called high endothelial venules (HEVs), located in the tissue parenchyma. HEVs have a unique morphology and phenotype, which enables them to interact with circulating lymphocytes efficiently. That is, the HEV endothelial cells have a tall and plump appearance, and constitutively express multiple adhesion molecules and chemokines on their surface. These molecules can interact with cognate receptors on circulating lymphocytes, thereby mediating the stepwise and sequential lymphocyte adhesion and transendothelial migration (TEM) at the HEV endothelial luminal surface. This review summarizes the fine morphological aspects of the unique HEV endothelial cells, with special reference to the spatial distribution of the adhesion molecules and chemokines that regulate lymphocyte migration.
Tohya
Kazuo
K
Department of Anatomy, Kansai University of Health Sciences, Osaka, Japan. ktohya@kansai.ac.jp
Umemoto
Eiji
E
Miyasaka
Masayuki
M
D000818:Animals; D015815:Cell Adhesion Molecules / Q000378:metabolism; D002450:Cell Communication; D002465:Cell Movement / Q000502:physiology; D018925:Chemokines / Q000378:metabolism; D042783:Endothelial Cells / Q000166:cytology* / Q000378:metabolism; D006801:Humans; D008198:Lymph Nodes / Q000166:cytology* / Q000378:metabolism; D008214:Lymphocytes / Q000166:cytology* / Q000378:metabolism; D010581:Peyer's Patches / Q000166:cytology* / Q000378:metabolism; D015398:Signal Transduction
D015815:Cell Adhesion Molecules; D018925:Chemokines