Abstract:
:Organ graft rejection is a T-cell-dependent process. The activation of alloreactive T cells requires stimulation of the T-cell receptor/CD3 complex by foreign major histocompatibility complex (MHC)-encoded gene products. However, accumulating evidence suggests that, in addition to T-cell receptor occupancy, other costimulatory signals are required to induce T-cell activation. Previously, the CD28 receptor expressed on T cells has been shown to serve as a surface component of a signal transduction pathway that can provide costimulation. In vitro, interaction of CD28 with its natural ligand B7 expressed on the surface of activated B cells or macrophages can act as a costimulus to induce proliferation and lymphokine production in antigen receptor-activated T cells. We now report evidence that stimulation of T cells by the CD28 ligand B7 is a required costimulatory event for the rejection of a MHC-incompatible cardiac allograft in vivo. These results demonstrate that the B7/CD28 activation pathway plays an important role in regulating in vivo T-cell responses.
journal_name
Proc Natl Acad Sci U S Aauthors
Turka LA,Linsley PS,Lin H,Brady W,Leiden JM,Wei RQ,Gibson ML,Zheng XG,Myrdal S,Gordon Ddoi
10.1073/pnas.89.22.11102keywords:
subject
Has Abstract,Author List Incompletepub_date
1992-11-15 00:00:00pages
11102-5issue
22eissn
0027-8424issn
1091-6490journal_volume
89pub_type
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