On the role of CD26 in CD4 memory T cells.
We studied an in vivo mouse model to evaluate the relationships between CD26--a glycoprotein with dipeptidyl peptidase IV (DPP-IV) activity implicated in the regulation of immune functions--and T cells expressing the effector/memory phenotype CD45RB. We report that CD26 does not define a differentiation stage of CD4 T cells because the density and frequency of CD26 on CD4 T cells from the spleen, inguinal and mesenteric lymph node was similar within the CD45RB+ (naïve) and CD45RB- (antigen primed) subsets. This observation was confirmed using CD4 T cells from a T-cell receptor transgenic (tg) model. CD4 tg T cells specific for ovalbumin (OVA) were adoptively transferred and challenged in vivo with antigen. CD26 expression was the same on naive and antigen-stimulated CD4 T cells. Depleting CD4 T cells with an anti-CD4 antibody preferentially depleted the CD45RB+ subset. In CD4 depleted animals CD26 expression was not altered on the CD45RB- subset but the density of CD26 was marginally increased on the remaining CD45RB+ CD4 T cells. The results suggest that, unlike the human, CD26 in the mouse was not directly linked with T cell activation.
Cordero
Oscar J
OJ
Department of Biochemistry and Molecular Biology, University of Santiago de Compostela, Santiago de Compostela, Spain. bnojcord@usc.es
Yang
Chun-Ping
CP
Bell
Eric B
EB
D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D002478:Cells, Cultured; D018819:Dipeptidyl Peptidase 4 / Q000502:physiology*; D007156:Immunologic Memory; D017493:Leukocyte Common Antigens / Q000502:physiology; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D016176:T-Lymphocyte Subsets / Q000201:enzymology / Q000276:immunology*
D017493:Leukocyte Common Antigens; D018819:Dipeptidyl Peptidase 4