Epstein-Barr virus latent membrane protein (LMP1) is not sufficient to maintain proliferation of B cells but both it and activated CD40 can prolong their survival.
AUTOR(ES)
Zimber-Strobl, U
RESUMO
Epstein-Barr virus (EBV) infects human primary B lymphocytes and induces and maintains proliferation of these cells efficiently in vitro. Mutants of Epstein-Barr virus which express EBV nuclear antigen 2 (EBNA2) in a conditional fashion allow dissection of individual contributions of viral genes to B cell immortalization. EBNA2 is a transcriptional activator of cellular and viral genes, including the viral latent membrane protein 1 (LMP1), which is essential for B cell immortalization and has oncogenic effects in non-lymphoid cells. To analyze the role of this gene in B cell immortalization, LMP1 was constitutively expressed in B cells infected with EBV carrying a conditional EBNA2 allele. In the absence of functional EBNA2, LMP1 was incapable of sustaining B cell proliferation in two independent assays but induced a phenotype consistent with prolonged cell viability. Activation of CD40 displayed a comparable phenotype. These data indicate that both CD40 activation and LMP1 expression may use a common pathway for B cell activation. Proliferation of human B cells, however, requires one or more additional signals triggered by EBNA2.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=452532Documentos Relacionados
- Control of Epstein–Barr virus reactivation by activated CD40 and viral latent membrane protein 1
- Expression of B7 (CD80) and CD40 antigens and the CD40 ligand in Hodgkin's disease is independent of latent Epstein—Barr virus infection
- Nuclear Factor κB-Dependent Activation of the Antiapoptotic bfl-1 Gene by the Epstein-Barr Virus Latent Membrane Protein 1 and Activated CD40 Receptor
- Epstein-Barr virus latent membrane protein (LMP1) and nuclear proteins 2 and 3C are effectors of phenotypic changes in B lymphocytes: EBNA-2 and LMP1 cooperatively induce CD23.
- Comparative Analysis of Signal Transduction by CD40 and the Epstein-Barr Virus Oncoprotein LMP1 In Vivo