title: Efficient lymphocyte migration across high endothelial venules of mouse Peyer's patches requires overlapping expression of L-selectin and beta7 integrin.
abstract: Lymphocyte migration into lymphoid organs is regulated by adhesion molecules including L-selectin and the beta7 integrins. L-selectin and alpha4beta7 are predominantly hypothesized to direct the selective migration of lymphocytes to peripheral lymph nodes and the gut-associated lymphoid tissues, respectively. To further characterize interactions between L-selectin and beta7 integrins during lymphocyte recirculation, mice deficient in both receptors (L-selectin/beta7 integrin-/-) were generated. The simultaneous loss of L-selectin and beta7 integrin expression prevented the majority of lymphocytes (>95% inhibition) from attaching to high endothelial venules (HEV) of Peyer's patches and other lymphoid tissues during in vitro binding assays. Moreover, the inability to bind HEV eliminated the vast majority of L-selectin/beta7 integrin-/- lymphocyte migration into Peyer's patches during short-term and long-term in vivo migration assays (>99% inhibition,p < 0.01). The lack of lymphocyte migration into Peyer's patches correlated directly with the dramatically reduced size and cellularity (99% reduced) of this tissue in L-selectin/beta7 integrin-/- mice. High numbers of injected L-selectin/beta7 integrin-/- lymphocytes remaining in the blood of wild-type mice correlated with markedly increased numbers of circulating lymphocytes in L-selectin/beta7 integrin-/- mice. Loss of either L-selectin or the beta7 integrins alone resulted in significant but incomplete inhibition of Peyer's patch migration. Collectively, the phenotype of L-selectin/beta7 integrin-/- mice demonstrates that these two receptors primarily interact along the same adhesion pathway that is required for the vast majority of lymphocyte migration into Peyer's patches.
authors.affiliation: Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA. steeb001@mc.duke.edu
authors.forename: D A
authors.initials: DA
authors.lastname: Steeber
authors.forename: M L
authors.initials: ML
authors.lastname: Tang
authors.forename: X Q
authors.initials: XQ
authors.lastname: Zhang
authors.forename: W
authors.initials: W
authors.lastname: Müller
authors.forename: N
authors.initials: N
authors.lastname: Wagner
authors.forename: T F
authors.initials: TF
authors.lastname: Tedder
mesh_terms: D000818:Animals; D002448:Cell Adhesion; D002465:Cell Movement; D004730:Endothelium, Vascular; D018928:Immunity, Mucosal; D039641:Integrin beta Chains; D016023:Integrins / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D019041:L-Selectin / Q000235:genetics / Q000502:physiology*; D008214:Lymphocytes / Q000166:cytology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D010581:Peyer's Patches / Q000166:cytology* / Q000276:immunology; D014699:Venules
chemical_list: D039641:Integrin beta Chains; D016023:Integrins; C091368:integrin beta7; D019041:L-Selectin