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Elevated serum transaminase levels of dengue patients indicate the possible impact of dengue virus infection on liver function. To elucidate the action of dengue virus infection in liver cells, an in vitro cell line system was established that mimicked the liver status of diverse clinical patients. Briefly, four hepatoma cell lines (HA22T, Huh7, Hep3B, and PLC) and one nonmalignant hepatocyte cell line (Chang liver) were included, representing various levels of tumorigenicity and differentiation. Our data showed that in these five cell lines, dengue-2 virus attached to each cell type equally well; however, this virus had higher replication rates and levels of virion production in differentiated Huh7, PLC, Hep3B, and Chang liver cells. Likewise, a lower replication rate was observed in the de-differentiated HA22T cells. Differentiation-related factors seem to play an important role in dengue virus replication. Further study showed that sodium butyrate (NaB, a differentiation inducer) treatment enhanced dengue virus replication in HA22T cells. Moreover, we found that the severity of morphologic aberration and the increase in aspartate aminotransferase (AST) levels correlated with the virus replication rate in the four infected hepatoma cells. In conclusion, we showed that dengue virus can infect diverse liver cells with differing replication efficiency, which causes cytopathic effects (CPEs) of diverse severity. Among the CPEs, the increased AST levels correlated with the clinical results from 24 dengue fever patients, who showed increased AST levels at the onset of fever. In summary, we find that dengue-2 virus replicates actively and causes severe CPEs in differentiated hepatoma cells. Factors related to differentiation as well as tumorigenicity seem to play critical roles, though the mechanisms of action remain unclear.

Although approximately 3 % of the world's population is infected with Hepatitis C virus (HCV), there is no prophylactic vaccine available. This study reports the design, cloning and purification of a single polyprotein comprising the HCV core protein and non-structural proteins NS3, NS4a, NS4b, NS5a and NS5b. The immunogenicity of this polyprotein, which was formulated in alum, oil-in-water emulsion MF59 or poly(DL-lactide co-glycolide) in the presence or absence of CpG adjuvant, was then determined in a murine model for induction of B-and T-cell responses. The addition of adjuvants or a delivery system to the HCV polyprotein enhanced serum antibody and T-cell proliferative responses, as well as IFN-c responses, by CD4 + T cells. The antibody responses were mainly against the NS3 and NS5 components of the polyprotein and relatively poor responses were elicited against NS4 and the core components. IFN-c responses, however, were induced against all of the individual components of the polyprotein. These data suggest that the HCV polyprotein delivered with adjuvants induces broad B-and T-cell responses and could be a vaccine candidate against HCV. INTRODUCTIONHepatitis C virus (HCV) is the leading cause of parenterally transmitted non-A, non-B viral hepatitis (Armstrong et al., 2000; Choo et al., 1989). Approximately 3 % of the world's population are infected with HCV (Cohen, 1999) and about 30 000 newly acquired HCV infections occur in the USA annually, mostly as a result of intravenous drug abuse (Alter, 1993). Currently, there is no vaccine available to prevent HCV infection and the only available therapies, IFN-a and ribavirin, are effective in fewer than half of the patients treated (McHutchison et al., 1998;Poynard et al., 1998). Therefore, there is an urgent need for the development of an efficacious vaccine to prevent HCV infection.We previously developed an experimental vaccine comprising a recombinant gpE1 and gpE2 heterodimer that protects chimpanzees against experimental challenge with both homologous (Choo et al., 1994) and heterologous (Coates et al., 2004) genotype 1a strains, which predominate in the USA and also occur worldwide. Natural immunity to HCV infection has been linked with early and broad Th1-type cellular immune responses to non-structural proteins NS3, NS4 and NS5 and the nucleocapsid (C) protein (Diepolder et al., 1995; Ferrari et al., 1997;Gerlach et al., 1999;Tsai et al., 1997). More recent data have shown the importance of Th1-type CD4 + T-cell responses in protection in chimpanzees (Grakoui et al., 2003) and humans (Lechner et al., 2000).To enhance the immunogenicity of recombinant proteinbased vaccines, adjuvants are required. The most widely used adjuvants are insoluble aluminium salts, generically called alum. However, although alum adjuvants have been used for decades and are generally safe, they induce predominantly a Th2-type cytokine response (Lindblad, 2004;Raz & Spiegelberg, 1999;Valensi et al., 1994). Therefore, alternative adjuvants may be required for the successful dev...

BackgroundChildren with a Cleft Lip and/or Palate (CL/P) have been reported to have poorer oral health than those without the condition. The consequences for these children can be particularly problematic due to implications for future treatments. Tooth brushing is an important behaviour contributing to children’s oral health, but is under researched in the CL/P population. The aim of the study is to explore the experience of maintaining tooth brushing among children in the United Kingdom (UK) with a CL/P and their parents.MethodsSemi-structured interviews were carried out with twenty-two parents and sixteen children with a CL/P (5-11 years), recruited at a cleft centre in the UK. Thematic analysis was used for data analysis.ResultsThree key themes were drawn from the qualitative data: first, parents of children with a CL/P generally had strong motivation to look after their children’s teeth but children’s motivation was inconsistent. Second, parents were primary enablers of children’s tooth brushing behaviour, often employing approaches adapted to their child’s characteristics to encourage tooth brushing. Third, a range of obstacles were encountered by parents and children in maintaining regular tooth brushing behaviours. They reported obstacles such as issues related to CL/P, ‘forgetting’ and childhood illness.ConclusionsThe paper suggests that parents of children with a CL/P need support to enact their intention to maintain regular tooth brushing and prioritise tooth brushing within the context of demanding and dynamic family life.