Publications by authors named "R Tafi"

Interleukin-11 (IL-11), a member of the IL-6 cytokine family, has potential pro-inflammatory and pro-fibrotic roles in pulmonary, hepatic, cardiovascular, renal and intestinal disease pathogenesis, including oncogenesis. The potential for therapeutic intervention in these disease spaces has therefore made the IL-11 signaling axis an attractive target in drug discovery, and antibody inhibitors of IL-11 signaling are currently under evaluation in Phase I/II clinical trials. While lower molecular weight small molecule and peptide inhibitors may offer the potential for improved tissue penetration, developability and manufacturing cost compared with a protein therapeutic, reports of such chemical matter in the literature are limited.

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Induction of multispecific, functional CD4+ and CD8+ T cells is the immunological hallmark of acute self-limiting hepatitis C virus (HCV) infection in humans. In the present study, we showed that gene electrotransfer (GET) of a novel candidate DNA vaccine encoding an optimized version of the nonstructural region of HCV (from NS3 to NS5B) induced substantially more potent, broad, and long-lasting CD4+ and CD8+ cellular immunity than naked DNA injection in mice and in rhesus macaques as measured by a combination of assays, including IFN-gamma ELISPOT, intracellular cytokine staining, and cytotoxic T cell assays. A protocol based on three injections of DNA with GET induced a substantially higher CD4+ T cell response than an adenovirus 6-based viral vector encoding the same Ag.

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Three percent of the world's population is chronically infected with the hepatitis C virus (HCV) and at risk of developing liver cancer. Effective cellular immune responses are deemed essential for spontaneous resolution of acute hepatitis C and long-term protection. Here we describe a new T-cell HCV genetic vaccine capable of protecting chimpanzees from acute hepatitis induced by challenge with heterologous virus.

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Success in resolving hepatitis C virus (HCV) infection has been correlated to vigorous, multispecific, and sustained CD8(+) T-cell response in humans and chimpanzees. The efficacy of inducing T-cell-mediated immunity by recombinant serotype 5 adenovirus vector has been proven in many animal models of infectious diseases, but its immunogenicity can be negatively influenced by preexisting immunity against the vector itself. To evaluate the less prevalent adenovirus serotype 6 (Ad6) as an alternative vector for and HCV vaccine development, we have generated serotype 5 and 6 adenoviral vectors directing expression of the nonstructural region of HCV (MRKAd5-NSmut and MRKAd6-NSmut).

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Hepatitis C Virus (HCV) is a major cause of chronic hepatitis, liver cirrhosis and hepatocellular carcinoma, worldwide, and the development of an effective vaccine represents a high priority goal. The Hyper Variable Region 1 (HVR1) of the second Envelope protein (E2) of HCV contains a principal neutralizing determinant, but it is highly variable among different isolates and it is involved in the escape from host immune response. Thus, to be effective, a vaccine should elicit a cross-reacting humoral response against the majority of viral variants.

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