Differential sensitivity to interferon influences the replication and transcription of Urabe AM9 mumps virus variants in nerve cells.
Microbes Infect 2007;
9:864-72. [PMID:
17533145 DOI:
10.1016/j.micinf.2007.03.005]
[Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2006] [Revised: 02/23/2007] [Accepted: 03/08/2007] [Indexed: 10/23/2022]
Abstract
Urabe AM9 mumps virus vaccine causes post-vaccination meningitis. Two variants of Urabe AM9 virus differ in their replication efficiency in human nerve cells, HN-A(1081) variant being more neurotropic than HN-G(1081). The effect of interferon (IFN) on viral replication and transcription was analyzed. Priming of nerve cells with IFN reduced more significantly the replication of HN-G(1081) variant (from 10(2.5) to 10(1.3) TCID(50)) than that of HN-A(1081) (from 10(3.5) to 10(2.6) TCID(50)). IFN-priming also reduced the transcription of HN-G(1081) genes, but not of HN-A(1081). The effect of viral infection on the transcription of cellular IFN responsive genes was analyzed. HN-A(1081) virus reduced the transcription of STAT1, STAT2, p48 and MxA in both unprimed and IFN-primed cells; whereas HN-G(1081) virus just reduced MxA transcription. Since rubulavirus V protein inhibits IFN signaling, the V mRNA was cloned and sequenced, finding that HN-G(1081) but not HN-A(1081) presented three extra G in the P/V edition site, producing the insertion of Gly156 in the V protein. Our results suggest that the replication efficiency of Urabe AM9 mumps virus variants is influenced by their sensitivity to interferon and their capacity to reduce the antiviral response.
Collapse