title: CCR7 ligands stimulate the intranodal motility of T lymphocytes in vivo.
abstract: In contrast to lymphocyte homing, little is known about molecular cues controlling the motility of lymphocytes within lymphoid organs. Applying intravital two-photon microscopy, we demonstrate that chemokine receptor CCR7 signaling enhances the intranodal motility of CD4(+) T cells. Compared to wild-type (WT) cells, the average velocity and mean motility coefficient of adoptively transferred CCR7-deficient CD4(+) T lymphocytes in T cell areas of WT recipients were reduced by 33 and 55%, respectively. Both parameters were comparably reduced for WT T lymphocytes migrating in T cell areas of plt/plt mice lacking CCR7 ligands. Importantly, systemic application of the CCR7 ligand CCL21 was sufficient to rescue the motility of WT T lymphocytes inside T cell areas of plt/plt recipients. Comparing the movement behavior of T cells in subcapsular areas that are devoid of detectable amounts of CCR7 ligands even in WT mice, we failed to reveal any differences between WT and plt/plt recipients. Furthermore, in both WT and plt/plt recipients, highly motile T cells rapidly accumulated in the subcapsular region after subcutaneous injection of the CCR7 ligand CCL19. Collectively, these data identify CCR7 and its ligands as important chemokinetic factors stimulating the basal motility of CD4(+) T cells inside lymph nodes in vivo.
authors.affiliation: Institute of Immunology, Hannover Medical School, 30625 Hannover, Germany.
authors.forename: Tim
authors.initials: T
authors.lastname: Worbs
authors.forename: Thorsten R
authors.initials: TR
authors.lastname: Mempel
authors.forename: Jasmin
authors.initials: J
authors.lastname: Bölter
authors.forename: Ulrich H
authors.initials: UH
authors.lastname: von Andrian
authors.forename: Reinhold
authors.initials: R
authors.lastname: Förster
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000378:metabolism*; D054415:Chemokine CCL19; D019742:Chemokines, CC / Q000378:metabolism / Q000502:physiology; D002634:Chemotaxis, Leukocyte / Q000235:genetics / Q000276:immunology*; D008024:Ligands; D008198:Lymph Nodes / Q000166:cytology / Q000276:immunology* / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D054400:Receptors, CCR7; D019707:Receptors, Chemokine / Q000172:deficiency / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D015398:Signal Transduction / Q000235:genetics / Q000276:immunology
chemical_list: C515461:Ccl19 protein, mouse; C515371:Ccr7 protein, mouse; D054415:Chemokine CCL19; D019742:Chemokines, CC; D008024:Ligands; D054400:Receptors, CCR7; D019707:Receptors, Chemokine