The CD45RB-associated epitope defined by monoclonal antibody CZ-1 is an activation and memory marker for mouse CD4 T cells.
Monoclonal antibody CZ-1 defines a novel sialic acid-dependent CD45RB-associated epitope. The CZ-1 antigen is expressed on the subpopulation of CD4 T cells that proliferate in response to IL-2. Because IL-2 responsiveness often denotes T cell activation, we examined the expression of the CZ-1 antigen on CD4 T cells taken from mice at various times during an infection with lymphocytic choriomeningitis virus (LCMV). The blast-sized CD4 T cells at Day 6 postinfection were CZ-1+. Further cell surface phenotyping showed that those blast cells activated at Day 6 postinfection were CD45RBdimPgp-1brightMEL-14-. This contrasts with the CZ-1-CD45RBbrightPgp-1bright/dimMEL-14+ resting cell population prior to infection. To determine if memory CD4 T cells continued to express the CZ-1 epitope long after resolution of the LCMV infection, CD4+CZ-1+ and CD4+CZ-1- populations were purified by cell sorting and placed in an in vitro proliferation assay with LCMV-infected antigen-presenting cells. It was found that the CD4+CZ-1+ population contained virtually all of the virus-specific memory. The CZ-1 epitope is therefore both an activation and a memory marker for murine CD4 T cells.
Department of Pathology, University of Massachusetts Medical Center, Worcester 01655, USA.
S M
SM
Varga
R M
RM
Welsh
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D000939:Epitopes; D007156:Immunologic Memory; D017493:Leukocyte Common Antigens / Q000032:analysis* / Q000276:immunology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D051381:Rats
D000911:Antibodies, Monoclonal; D000939:Epitopes; D017493:Leukocyte Common Antigens