Varga S M, Welsh R M
Department of Pathology, University of Massachusetts Medical Center, Worcester 01655, USA.
Cell Immunol. 1996 Jan 10;167(1):56-62. doi: 10.1006/cimm.1996.0007.
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.
单克隆抗体CZ-1定义了一种新的唾液酸依赖性CD45RB相关表位。CZ-1抗原在对白细胞介素-2（IL-2）作出反应而增殖的CD4 T细胞亚群上表达。由于IL-2反应性通常表示T细胞活化，我们检测了在淋巴细胞性脉络丛脑膜炎病毒（LCMV）感染期间不同时间从小鼠获取的CD4 T细胞上CZ-1抗原的表达。感染后第6天的母细胞大小的CD4 T细胞为CZ-1阳性。进一步的细胞表面表型分析表明，那些在感染后第6天被激活的母细胞为CD45RB低表达Pgp-1高表达MEL-14阴性。这与感染前的CZ-1阴性CD45RB高表达Pgp-1高表达/低表达MEL-14阳性静息细胞群体形成对比。为了确定记忆性CD4 T细胞在LCMV感染消退后是否长时间持续表达CZ-1表位，通过细胞分选纯化CD4⁺CZ-1⁺和CD4⁺CZ-1⁻群体，并将其与感染LCMV的抗原呈递细胞进行体外增殖试验。发现CD4⁺CZ-1⁺群体几乎包含了所有病毒特异性记忆细胞。因此，CZ-1表位既是小鼠CD4 T细胞的活化标志物，也是记忆标志物。
