Razi-Wolf Z, Freeman G J, Galvin F, Benacerraf B, Nadler L, Reiser H
Department of Pathology, Harvard Medical School, Boston, MA 02115.
Proc Natl Acad Sci U S A. 1992 May 1;89(9):4210-4. doi: 10.1073/pnas.89.9.4210.
The murine B7 (mB7) protein is a potent costimulatory molecule for the T-cell receptor (TCR)-mediated activation of murine CD4+ T cells. We have previously shown that stable mB7-transfected Chinese hamster ovary (CHO) cells but not vector-transfected controls synergize with either anti-CD3 monoclonal antibody-induced or concanavalin A-induced T-cell activation, resulting ultimately in lymphokine production and proliferation. We now have generated a hamster anti-mB7 monoclonal antibody. This reagent recognizes a protein with an apparent molecular mass of 50-60 kDa. The mB7 antigen is expressed on activated B cells and on peritoneal exudate cells (PECs). Antibody blocking experiments demonstrate that mB7 is the major costimulatory molecule expressed by PECs for the activation of murine CD4+ T cells. This suggests an important role for mB7 during immune-cell interactions. We have also surveyed a panel of murine cell lines capable of providing costimulatory activity. Our results indicate that mB7 is the major costimulatory molecule on some but not all cell lines and that there may be additional molecules besides mB7 that can costimulate the activation of murine CD4+ T cells.
鼠B7（mB7）蛋白是一种强大的共刺激分子，可促进T细胞受体（TCR）介导的鼠CD4 + T细胞活化。我们之前已经表明，稳定转染mB7的中国仓鼠卵巢（CHO）细胞，而非载体转染的对照细胞，可与抗CD3单克隆抗体诱导的或伴刀豆球蛋白A诱导的T细胞活化协同作用，最终导致淋巴因子产生和细胞增殖。我们现在制备了一种仓鼠抗mB7单克隆抗体。该试剂识别一种表观分子量为50 - 60 kDa的蛋白质。mB7抗原在活化的B细胞和腹腔渗出细胞（PEC）上表达。抗体阻断实验表明，mB7是PEC表达的用于活化鼠CD4 + T细胞的主要共刺激分子。这表明mB7在免疫细胞相互作用中起重要作用。我们还检测了一组能够提供共刺激活性的鼠细胞系。我们的结果表明，mB7是某些但并非所有细胞系上的主要共刺激分子，并且除mB7之外可能还有其他分子能够共刺激鼠CD4 + T细胞的活化。
