NF-kappaB only partially mediates Epstein-Barr virus latent membrane protein 1 activation of B cells.
1998 (English)In: Journal of General Virology, ISSN 0022-1317, E-ISSN 1465-2099, Vol. 79 ( Pt 9), 2117-25 p.Article in journal (Refereed) Published
The latent membrane protein 1 (LMP1) of Epstein-Barr virus (EBV) is required for EBV-induced immortalization of human B cells and causes tumorigenic transformation of cell lines. LMP1 expression induces phenotypic changes resembling B cell activation, such as cell size increase and up-regulation of cell surface activation markers. LMP1 contains two domains that activate the transcription factor NF-kappaB, one through interactions with TRAF proteins and the other with the TRADD protein. The purpose of the present study was to investigate the importance of NF-kappaB induction in the up-regulation of the B cell activation markers ICAM-1 and CD71 by LMP1. This study shows that expression of LMP1 activates transcription from p50/p65- and c-Rel-responsive promoters, and that this activity can be completely inhibited by expression of a dominant inhibitory IkappaB mutant. ICAM-1 and CD71 are nevertheless up-regulated by LMP1 in primary B cells and cell lines expressing the dominant IkappaB. Furthermore, LMP1-induced cell size increase of primary B cells was unaffected by IkappaB expression. It was concluded that even when LMP1 is unable to activate NF-kappaB, it is still capable of inducing certain characteristics of activated B cells, strongly suggesting that LMP1 can also activate cells independently of NF-kappaB.
Place, publisher, year, edition, pages
1998. Vol. 79 ( Pt 9), 2117-25 p.
IdentifiersURN: urn:nbn:se:umu:diva-33076PubMedID: 9747720OAI: oai:DiVA.org:umu-33076DiVA: diva2:309933