Time courses of B7 family molecules expressed on activated T-cells and their biological significance.
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.
Sun
Zhong-Wen
ZW
Jiangsu Key Laboratory of Clinical Immunology, Biotechnology Research Institute, Suzhou University, Suzhou 215007, PR China.
Qiu
Yu-Hua
YH
Shi
Yun-Jie
YJ
Tao
Ran
R
Chen
Jie
J
Ge
Yan
Y
Hu
Yu-min
YM
Ma
Hong-bing
HB
Shi
Qin
Q
Zhang
Xue-guang
XG
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*
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