RESUMO
Expression vectors that are based on live human rhinoviruses (HRVs) are attractive, yet often overlooked in vaccine development due to their limited capacity for foreign gene inserts and poor genetic stability. This chapter describes a novel methodology to engineer a replication-competent genetically stable recombinant HRV (rHRV) without affecting viral replication capability. We have previously used these methods to generate live, genetically stable recombinant HRVs encoding HIV Gag and Tat proteins (rHRV-Gag-Tat), a potential mucosally targeted HIV vaccine.
Assuntos
Enterovirus/fisiologia , Produtos do Gene gag do Vírus da Imunodeficiência Humana/genética , Produtos do Gene tat do Vírus da Imunodeficiência Humana/genética , Enterovirus/genética , Vetores Genéticos , Células HeLa , Humanos , Replicação Viral , Produtos do Gene gag do Vírus da Imunodeficiência Humana/imunologia , Produtos do Gene tat do Vírus da Imunodeficiência Humana/imunologiaRESUMO
Chronic hepatitis C virus (HCV) infection represents a major health threat to global population. In India, approximately 15-20% of cases of chronic liver diseases are caused by HCV infection. Although, new drug treatments hold great promise for HCV eradication in infected individuals, the treatments are highly expensive. A vaccine for preventing or treating HCV infection would be of great value, particularly in developing countries. Several preclinical trials of virus-like particle (VLP) based vaccine strategies are in progress throughout the world. Previously, using baculovirus based system, we have reported the production of hepatitis C virus-like particles (HCV-LPs) encoding structural proteins for genotype 3a, which is prevalent in India. In the present study, we have generated HCV-LPs using adenovirus based system and tried different immunization strategies by using combinations of both kinds of HCV-LPs with other genotype 3a-based immunogens. HCV-LPs and peptides based ELISAs were used to evaluate antibody responses generated by these combinations. Cell-mediated immune responses were measured by using T-cell proliferation assay and intracellular cytokine staining. We observed that administration of recombinant adenoviruses expressing HCV structural proteins as final booster enhances both antibody as well as T-cell responses. Additionally, reduction of binding of VLP and JFH1 virus to human hepatocellular carcinoma cells demonstrated the presence of neutralizing antibodies in immunized sera. Taken together, our results suggest that the combined regimen of VLP followed by recombinant adenovirus could more effectively inhibit HCV infection, endorsing the novel vaccine strategy.
