Cytolytic CD4+-T-Cell Clones Reactive to EBNA1 Inhibit Epstein-Barr Virus-Induced B-Cell Proliferation†
AUTOR(ES)
Nikiforow, Sarah
FONTE
American Society for Microbiology
RESUMO
In the absence of immune surveillance, Epstein-Barr virus (EBV)-infected B cells generate neoplasms in vivo and transformed cell lines in vitro. In an in vitro system which modeled the first steps of in vivo immune control over posttransplant lymphoproliferative disease and lymphomas, our investigators previously demonstrated that memory CD4+ T cells reactive to EBV were necessary and sufficient to prevent proliferation of B cells newly infected by EBV (S. Nikiforow et al., J. Virol. 75:3740-3752, 2001). Here, we show that three CD4+-T-cell clones reactive to the latent EBV antigen EBNA1 also prevent the proliferation of newly infected B cells from major histocompatibility complex (MHC) class II-matched donors, a crucial first step in the transformation process. EBNA1-reactive T-cell clones recognized B cells as early as 4 days after EBV infection through an HLA-DR-restricted interaction. They secreted Th1-type and Th2-type cytokines and lysed EBV-transformed established lymphoblastoid cell lines via a Fas/Fas ligand-dependent mechanism. Once specifically activated, they also caused bystander regression and bystander killing of non-MHC-matched EBV-infected B cells. Since EBNA1 is recognized by CD4+ T cells from nearly all EBV-seropositive individuals and evades detection by CD8+ T cells, EBNA1-reactive CD4+ T cells may control de novo expansion of B cells following EBV infection in vivo. Thus, EBNA1-reactive CD4+-T-cell clones may find use as adoptive immunotherapy against EBV-related lymphoproliferative disease and many other EBV-associated tumors.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=254269Documentos Relacionados
- CD4+ T-Cell Effectors Inhibit Epstein-Barr Virus-Induced B-Cell Proliferation
- Prevention of Epstein-Barr virus-induced B-cell outgrowth by interferon alpha.
- Suppressor T cell clones from patients with acute Epstein-Barr virus-induced infectious mononucleosis.
- Dual EBNA1 promoter usage by Epstein-Barr virus in human B-cell lines expressing unique intermediate cellular phenotypes.
- Inhibition of Epstein-Barr virus-induced growth proliferation by a nuclear antigen EBNA2-TAT peptide