Mutants defective in herpes simplex virus type 2 ICP4: isolation and preliminary characterization.

Our results, combined with observations from other studies and approaches, support current models for HSV-1 DNA packaging including putative assignment of roles for several of the HSV-1 proteins involved in the packaging process. Goat anti-mouse Alexa Fluor 488-IgG, 4′,6′-diamidino-2-phenylindole (DAPI), and FluoZin-3 AM were from Life Technologies (Carlsbad, CA). 1). Small arrowheads indicate plaque ulceration with hemorrhage and thrombus formation. W. Vero cells were plated in 35-mm plastic dishes which contained a gridded, glass insert, enabling the localization and recovery of individual cells. Plaque assay and cell viability.For growth inhibition assays, Vero, HFT, and HFF cells were infected with wild-type (KOS) or mutant (dlsactk) virus at a multiplicity of infection (MOI) of 10.

Cells were then overlaid with medium containing 1.2% methyl cellulose and various concentrations of ODNs and incubated at 37°C for 2 days. sinense, on HSV-1 α, β, and γ gene expression and DNA replication in Vero cells was evaluated. The latter recombinant virus expresses green fluorescent protein (GFP) under the control of a cytomegalovirus promoter; the construct was inserted in an intergenic region between UL3 and UL4 (gift from P. In both humans and mice, stimuli known to impair CD8+ T-cell function (stress, immunosuppressive drugs, and exposure to UV irradiation) lead to HSV-1 reactivation from latency (5, 14, 25, 26, 28). In the absence of US3 kinase activity, the UL31 and UL34 proteins colocalize in punctate extensions of the nuclear membrane (31). Plasmids and viruses.HSV strain F (wild type) was acquired through the American Type Culture Collection (Manassas, Va.). Clinical isolates MMA and WTWIA (gifts from P.

B78-H1 mouse melanoma cells expressing gD receptor HVEM (A10) or nectin-1 (C10) (45) were grown in DMEM supplemented with 5% FCS and 500 μg of G418 per ml. These cell lines as well as A549 cells were maintained in Dulbecco’s modified Eagle medium (DMEM) supplemented with 10% fetal bovine calf serum, 100 U of penicillin/ml, 1% streptomycin, and 1% l-glutamine (all from Gibco). Their observations led those authors to propose that low pH is an important factor in the activation of gB for fusion with endosomal membranes during virus entry (17). These endosomal vesicles gradually accumulate internal vesicles. This may not be the complete list of references from this article. The effects may be long lasting due to the high affinity and stability of the sulfated compound-virus complex, as evidenced by surface plasmon resonance studies. Together, these results suggest that soluble gB binds specifically to the surface of different cell types independently of HSPG and CSPG and that by doing so, the protein inhibits entry.

In current models, gC and/or gB binds cell surface heparan sulfate proteoglycans, bringing the viral envelope and plasma membrane close enough for fusion to occur (69). Get a printable copy (PDF file) of the complete article (1.9M), or click on a page image below to browse page by page. Sign up to view the full version. Get a printable copy (PDF file) of the complete article (1.5M), or click on a page image below to browse page by page. Received 10 November 2003. Mutant forms of gB and gK apparently disregulate the fusion process, whereas wild-type forms of gB and gK can act to suppress membrane fusion induced by their mutant counterparts. Thus, low pH causes local conformational changes in gB that are very different from the large-scale fusogenic conformational changes in other viral fusion proteins.

The modification was mediated by the viral protein kinase U(S)3 and occurred between 3 and 6 h after infection with wild-type virus but was delayed in rabbit skin cells infected with HSV-1(vCPc0) mutant, concordant with a delay in the expression of viral genes. We identify here the viral glycoprotein B (gB) as the predominant CD1d-interacting protein. We investigated the impact of HSV-1 infection on the MHCII processing pathway, which is critical to generate CD4(+) T cell help. In contrast, the levels of viral replication of an ICP22-null mutant virus were similar in both p53−/− and p53+/+ cells. An effective vaccine is not yet available. A class of compensatory mutants characterized by a deletion which results in the juxtaposition of the alpha47 promoter next to US11, a gamma2 (late) gene in wild-type virus-infected cells, has been described. Marker rescue and sequencing experiments showed that resistance was due to at least one of three mutations in the UL27 gene which result in amino acid changes in glycoprotein B (gB).

The chimeric constructs were then inserted into the HSV-1 genome and specifically into the thymidine kinase gene by homologous recombination through flanking sequences. Infectious herpes simplex virus (HSV) particles consist of three complex components: a DNA-containing nucleocapsid, an amorphous tegument layer composed of viral proteins, and a lipid bilayer envelope containing specific viral proteins. The true incidence of herpetic infections of the larynx is unknown. Herpes simplex viruses (HSVs) are prevalent human pathogens that establish latency in human neuronal cells and efficiently evade the immune system.