RESUMEN
CIGB-230, a mixture of a DNA plasmid expressing hepatitis C virus (HCV) structural antigens and a HCV recombinant capsid protein, has demonstrated to elicit strong immune responses in animals. The present study evaluated the plasmid biodistribution after the administration of CIGB-230 in mice, as well as toxicity of this vaccine candidate in rats. In the biodistribution study, mice received single or repeated intramuscular injections of CIGB-230, 50 microg of plasmid DNA mixed with 5 microg of Co.120 protein. Plasmid presence was assessed in ovaries, kidney, liver, pancreas, mesenteric ganglion, blood, and muscle of the injection site by a qualitative polymerase chain reaction. The toxicology evaluation included treatment groups receiving doses 5, 15, or 50 times higher, according to the body weight, than the expected therapeutic clinical dose. During the first hour after repeated inoculation, a promiscuous distribution was observed. However, 3 months later, plasmid could not be detected in any tissue. There was an absence of detectable adverse effects on key toxicology parameters and no damage evidenced in inspected organs and tissues. These results indicate that CIGB-230 is nontoxic at local and systemic levels and no concerns about persistence are observed, which support clinical testing of this vaccine candidate against HCV.
Asunto(s)
Hepacivirus/inmunología , Hepatitis C/prevención & control , Vacunas de ADN/farmacocinética , Vacunas de ADN/toxicidad , Vacunas contra Hepatitis Viral/farmacocinética , Vacunas contra Hepatitis Viral/toxicidad , Animales , Femenino , Hepacivirus/genética , Antígenos de la Hepatitis/genética , Antígenos de la Hepatitis/inmunología , Hepatitis C/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratas , Ratas Sprague-Dawley , Distribución Tisular , Pruebas de Toxicidad , Proteínas del Núcleo Viral/genética , Proteínas del Núcleo Viral/inmunologíaRESUMEN
SUMMARY: Hepatitis C virus (HCV) is a worldwide health problem. No vaccine is available against this pathogen and therapeutic treatments currently in use are of limited efficacy. In the present study, the immunogenicity of the therapeutic vaccine candidate CIGB-230, based on the mixture of pIDKE2, a plasmid expressing HCV structural antigens, with a recombinant HCV core protein, Co.120, was evaluated. CIGB-230 was administered by intramuscular injection on weeks 0, 4, 8, 12, 16 and 20 to 15 HCV-chronically infected individuals, non-responders to previous treatment with interferon (IFN) plus ribavirin. Interestingly, following the final immunization, neutralizing antibody responses against heterologous viral pseudoparticles were modified in eight individuals, including six de novo responders. In addition, 73% of vaccinees exhibited specific T cell proliferative response and T cell IFN-gamma secretory response 24 weeks after primary immunization with CIGB-230. Furthermore, 33.3% of individuals developed de novo cellular immune response against HCV core and the number of patients (46.7% at the end of treatment) with cellular immune response against more than one HCV structural antigen increased during vaccination (P = 0.046). In addition, despite persistent detection of HCV RNA, more than 40% percent of vaccinated individuals improved or stabilized liver histology, particularly reducing fibrosis, which correlated with cellular immune response against more than one HCV antigen (P = 0.0053). In conclusion, CIGB-230 is a promising candidate for effective therapeutic interventions based on its ability for enhancing the immune response in HCV chronically infected individuals.
Asunto(s)
Hepacivirus/inmunología , Anticuerpos contra la Hepatitis C/sangre , Hepatitis C Crónica/inmunología , Linfocitos T/inmunología , Vacunas de ADN/inmunología , Vacunas contra Hepatitis Viral/inmunología , Adulto , Femenino , Hepacivirus/genética , Hepacivirus/aislamiento & purificación , Antígenos de la Hepatitis/genética , Antígenos de la Hepatitis/inmunología , Hepatitis C Crónica/prevención & control , Hepatitis C Crónica/virología , Humanos , Inmunización , Interferón gamma/biosíntesis , Activación de Linfocitos , Masculino , Persona de Mediana Edad , Pruebas de Neutralización , ARN Viral/sangre , Resultado del Tratamiento , Vacunas de ADN/administración & dosificación , Vacunas de ADN/uso terapéutico , Proteínas del Núcleo Viral/genética , Proteínas del Núcleo Viral/inmunología , Vacunas contra Hepatitis Viral/administración & dosificación , Vacunas contra Hepatitis Viral/uso terapéutico , Carga ViralRESUMEN
The hepatitis E virus (HEV) has a global distribution and is known to have caused large waterborne epidemics of icteric hepatitis. The transmission is primarily fecal-oral. Some reports have suggested parenteral transmission of HEV from its association to hepatitis B or hepatitis C infection, or due to the development of hepatitis E after blood transfusion. Though most of the developing countries in Asia and Africa have been shown to be endemic for HEV infection, studies in the Latin American countries have been limited to Mexico, Brazil and Venezuela. We have developed an enzyme immunoassay (EIA) for IgM and IgG antibodies to a recombinant protein containing antigenic epitopes of the ORF3 region of the HEV. This system, as well as a commercial kit that includes ORF2 and ORF3 antigenic epitopes, were used to study the prevalence of anti-HEV antibodies in a sample of Cuban blood donors, acute hepatitis cases and individuals subjected to plasmapheresis. The incidence of anti-HEV IgM was compared with other viral hepatitis markers. Our findings suggest that infections due to HEV are an important viral cause of sporadic hepatitis in Cuba, and that HEV is endemic to this region of the world.