Naive, effector, and memory T lymphocytes efficiently scan dendritic cells in vivo: contact frequency in T cell zones of secondary lymphoid organs does not depend on LFA-1 expression and facilitates survival of effector T cells.
Contact between T cells and dendritic cells (DCs) is required for their subsequent interaction leading to the induction of adaptive immune responses. Quantitative data regarding the contact frequencies of T cell subsets in different lymphoid organs and species are lacking. Therefore, naive, effector, and memory CD4 T cells were injected into rats in absence of the cognate Ag, and 0.5-96 h later, spleen, lymph nodes, and Peyer's patches were removed. Cryosections were analyzed for contact between donor T cells and endogenous DCs in the T cell zone, and donor cell proliferation. More than 60% of injected naive CD4 T cells were in contact with endogenous DCs at all time points and in all organs analyzed. Surprisingly, we were unable to detect any differences between naive, effector, and memory CD4 T cells despite different expression levels of surface molecules. In addition, contact frequency was similar for T cells in lymphoid organs of rats, mice, and humans; it was unaffected by the absence of LFA-1 (CD11a/CD18), and sustained effector T cells in an activated state. Thus, the architecture of the T cell zone rather than expression patterns of surface molecules determines the contact efficiency between T cells and DCs in vivo.
Westermann
Jürgen
J
Institute of Anatomy, University of Lübeck, Lübeck, Germany. westermann@anat.uni-luebeck.de
Bode
Ulrike
U
Sahle
Andrea
A
Speck
Uwe
U
Karin
Nathan
N
Bell
Eric B
EB
Kalies
Kathrin
K
Gebert
Andreas
A
D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology* / Q000637:transplantation; D015815:Cell Adhesion Molecules / Q000502:physiology; D002450:Cell Communication / Q000276:immunology*; D049109:Cell Proliferation; D002470:Cell Survival / Q000276:immunology; D018925:Chemokines / Q000502:physiology; D003713:Dendritic Cells / Q000166:cytology / Q000276:immunology*; D007156:Immunologic Memory; D007275:Injections, Intravenous; D016169:Lymphocyte Function-Associated Antigen-1 / Q000096:biosynthesis* / Q000502:physiology; D008221:Lymphoid Tissue / Q000166:cytology / Q000276:immunology*; D051379:Mice; D018345:Mice, Knockout; D051381:Rats; D011917:Rats, Inbred Lew; D016192:Resting Phase, Cell Cycle / Q000276:immunology*; D013045:Species Specificity; D016176:T-Lymphocyte Subsets / Q000166:cytology / Q000276:immunology* / Q000637:transplantation
D015815:Cell Adhesion Molecules; D018925:Chemokines; D016169:Lymphocyte Function-Associated Antigen-1