Expression and co-stimulatory function of B7-2 on murine CD4+ T cells.
Co-stimulatory signals mediated by the interaction of B7-1/B7-2 with CD28 are important for the activation of CD4+ T cells stimulated with antigen on antigen-presenting cells. There are controversies about the expression and function of B7-1/B7-2 on CD4+ T cells. The aim of this study was to analyze the expression of B7-1/B7-2 on naive and memory CD4+ T cells and the co-stimulatory function in the activation of naive CD4+ T cells stimulated by TCR ligation. Present results indicate that memory CD4+ T cells express B7-2 molecules on their surface, whereas naive CD4+ T cells do not. Neither memory nor naive CD4+ T cells expressed B7-1 molecule on their surface, although B7-1 mRNA was faintly expressed in memory T cells. B7-2 molecules expressed on memory T cells co-stimulated CD4+ naive T cells stimulated with plate-coated anti-CD3 to produce IL-2. Naive CD4+ T cells were shown to express B7-2 after co-stimulation with B7-2 and TCR ligation, because the naive T cells stimulated with anti-CD3 and B7-2CHO expressed B7-2 on their surface, although it remained to be studied whether the co-stimulation with B7-2 directly induced B7-2 expression on naive T cells. Our present results indicate that memory CD4+ T cells play some role in the activation of naive CD4+ T cells through the co-stimulation with B7-2 molecules.
Hakamada-Taguchi
R
R
Department of Allergology, University of Tokyo, Japan.
Kato
T
T
Ushijima
H
H
Murakami
M
M
Uede
T
T
Nariuchi
H
H
D000818:Animals; D015703:Antigens, CD / Q000378:metabolism*; D018122:B7-1 Antigen / Q000378:metabolism; D051940:B7-2 Antigen; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D004306:Dose-Response Relationship, Immunologic; D005260:Female; D015870:Gene Expression; D007156:Immunologic Memory; D007376:Interleukin-2 / Q000096:biosynthesis; D008562:Membrane Glycoproteins / Q000378:metabolism*; D051379:Mice; D008809:Mice, Inbred C3H; D012333:RNA, Messenger / Q000235:genetics; D011948:Receptors, Antigen, T-Cell / Q000502:physiology*; D015398:Signal Transduction; D013154:Spleen / Q000166:cytology; D016176:T-Lymphocyte Subsets / Q000276:immunology
D015703:Antigens, CD; D018122:B7-1 Antigen; D051940:B7-2 Antigen; C497965:Cd86 protein, mouse; D007376:Interleukin-2; D008562:Membrane Glycoproteins; D012333:RNA, Messenger; D011948:Receptors, Antigen, T-Cell