title: Time courses of B7 family molecules expressed on activated T-cells and their biological significance.
abstract: B7 family molecules are mainly expressed on the outer membrane of antigen-presenting cells. Here, our results demonstrate that CD80, CD86, and PD-L1 molecules are also expressed on T-cells that have been activated by simultaneous exposure to anti-CD3 and anti-CD28 mAbs, but PD-L2 and GL50 molecules were not detectable during the first six days of culture that follow such stimulation. We have analysed the time course of B7 family molecule expression on activated T-cells. CD28 and its ligands, CD80/CD86, have a high degree of co-localization and exhibit compartmental distribution on the membrane of activated T-cells, which is visualized by confocal microscopy. Interestingly, the co-localization of PD-1 and its ligand also exhibit similar phenomenon. Additionally, we provide evidence indicating that the CD80, CD86, and PD-L1 molecules are functional, since T-cells expressing B7 family molecules are able to stimulate the proliferation of highly purified allogeneic or autologous T-cells. Anti-CD80, anti-CD86, and soluble CD28-Ig protein could significantly attenuate the proliferation of T-cells, whereas anti-PD-L1 mAb may lead to the expansion of activated T-cells. We can conclude that activated T-cells expressing B7 family molecules could act as "APC" to trigger purified T-cells, and B7 family molecules play important roles during the activation of T-cells. These results indicate a need for further work, exploring the regulatory roles these molecules may play in immune responses.
authors.affiliation: Jiangsu Key Laboratory of Clinical Immunology, Biotechnology Research Institute, Suzhou University, Suzhou 215007, PR China.
authors.forename: Zhong-Wen
authors.initials: ZW
authors.lastname: Sun
authors.forename: Yu-Hua
authors.initials: YH
authors.lastname: Qiu
authors.forename: Yun-Jie
authors.initials: YJ
authors.lastname: Shi
authors.forename: Ran
authors.initials: R
authors.lastname: Tao
authors.forename: Jie
authors.initials: J
authors.lastname: Chen
authors.forename: Yan
authors.initials: Y
authors.lastname: Ge
authors.forename: Yu-min
authors.initials: YM
authors.lastname: Hu
authors.forename: Hong-bing
authors.initials: HB
authors.lastname: Ma
authors.forename: Qin
authors.initials: Q
authors.lastname: Shi
authors.forename: Xue-guang
authors.initials: XG
authors.lastname: Zhang
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D015703:Antigens, CD; D018122:B7-1 Antigen / Q000378:metabolism*; D051940:B7-2 Antigen / Q000378:metabolism*; D060890:B7-H1 Antigen; D018106:CD28 Antigens / Q000276:immunology; D017252:CD3 Complex / Q000276:immunology; D002478:Cells, Cultured; D006801:Humans; D047569:Laser Scanning Cytometry / Q000379:methods; D007963:Leukocytes, Mononuclear; D008213:Lymphocyte Activation / Q000276:immunology; D008562:Membrane Glycoproteins / Q000378:metabolism*; D051379:Mice; D010455:Peptides / Q000378:metabolism*; D013601:T-Lymphocytes / Q000378:metabolism*
chemical_list: D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D018122:B7-1 Antigen; D051940:B7-2 Antigen; D060890:B7-H1 Antigen; C423236:CD274 protein, human; D018106:CD28 Antigens; D017252:CD3 Complex; D008562:Membrane Glycoproteins; D010455:Peptides