Item Type: | Article |
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Title: | Expression of a hypoglycosylated form of CD86 (B7-2) on human T cells with altered binding properties to CD28 and CTLA-4 |
Creators Name: | Hoellsberg, P., Scholz, C., Anderson, D.E., Greenfield, E.A., Kuchroo, V.K., Freeman, G.J. and Hafler, D.A. |
Abstract: | CD80 (B7-1) and CD86 (B7-2) on APC provide a major costimulatory signal through interactions with CD28 on T cells. Absent from resting human T cells, CD86 is up-regulated early upon T cell activation, whereas CD80 expression appears later. Whereas T cell expression of CD80 has been implicated in costimulation, the functional significance of CD86 expression on T cells is unclear. We now demonstrate that CD86 expressed on human CD4+ T cell clones does not provide a costimulatory signal for other CD4+ T cell clones. Binding studies using CD28-Ig and CTLA-4-Ig fusion proteins demonstrate that CD86 expressed on T cells has significantly reduced binding affinity for CTLA-4 and no detectable binding to CD28. Biochemical analysis demonstrates that post-translational modifications of CD86 in human T cells are different from those of CD86-transfected Chinese hamster ovary cells or EBV-transformed B cells, in that T cells express a hypoglycosylated form of CD86 on the surface membrane. Thus, our results suggest that while CD86 is expressed on a number of different cell types, its costimulatory function and affinity for its ligands may be regulated by cell type-specific post-translational modifications. |
Keywords: | CD Antigens, CD4-Positive T-Lymphocytes, CHO Cells, Clone Cells, Differentiation Antigens, Glycosylation, Immunoconjugates, Lymphocyte Activation, Membrane Glycoproteins, Monoclonal Antibodies, Protein Binding, T-Lymphocyte Subsets, Transformed Cell Line, Animals, Cricetinae |
Source: | Journal of Immunology |
ISSN: | 0022-1767 |
Publisher: | American Association of Immunologists |
Volume: | 159 |
Number: | 10 |
Page Range: | 4799-4805 |
Date: | 15 November 1997 |
Official Publication: | http://www.jimmunol.org/cgi/content/abstract/159/10/4799 |
PubMed: | View item in PubMed |
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