title: Abrogation of CCL21 chemokine function by transgenic over-expression impairs T cell immunity to local infections.
abstract: The CC chemokine receptor 7 (CCR7) and its two ligands, CCL21 and CCL19, play an important role in migration of immune cells to lymphoid tissue. To analyze the function of CCR7 in T cell immunity to infectious agents in vivo, transgenic (tg) mice expressing CCL21 in an ubiquitous fashion were generated. These mice contained high amounts of CCL21 in the serum ( approximately 0.3 microg/ml that resulted in CCR7 down-regulation and in a strongly impaired migration of T cells toward CCL21 in vitro. Lymph nodes in CCL21-tg mice were reduced in size but with intact microanatomy and normal distribution of T and B cells. CCL21-tg mice showed a significantly decreased CD8 T cell response to lymphocytic choriomeningitis virus after footpad infection, whereas the response after systemic infection was not altered. Likewise, the CD4 T cell response to footpad infection with Leishmania major was considerably lowered and CCL21-tg mice failed to clear parasites from infected skin. Taken together, these data demonstrate the importance of CCR7 in mediating T cell immunity to viral and parasitic pathogens after local infection.
authors.affiliation: Department of Immunology, Institute of Medical Microbiology and Hygiene, University of Freiburg, Freiburg, Germany.
authors.forename: Heike
authors.initials: H
authors.lastname: Unsoeld
authors.forename: Katja
authors.initials: K
authors.lastname: Mueller
authors.forename: Ulrike
authors.initials: U
authors.lastname: Schleicher
authors.forename: Christian
authors.initials: C
authors.lastname: Bogdan
authors.forename: Jörg
authors.initials: J
authors.lastname: Zwirner
authors.forename: David
authors.initials: D
authors.lastname: Voehringer
authors.forename: Hanspeter
authors.initials: H
authors.lastname: Pircher
mesh_terms: D000818:Animals; D001117:Arenaviridae Infections / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism; D054421:Chemokine CCL21 / Q000097:blood / Q000235:genetics / Q000276:immunology*; D018320:Leishmania major / Q000276:immunology; D016773:Leishmaniasis, Cutaneous / Q000276:immunology*; D008198:Lymph Nodes / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D008217:Lymphocytic choriomeningitis virus / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D054400:Receptors, CCR7 / Q000276:immunology* / Q000378:metabolism; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D054421:Chemokine CCL21; D054400:Receptors, CCR7