An in-house real-time polymerase chain reaction: standardisation and comparison with the Cobas Amplicor HBV monitor and Cobas AmpliPrep/Cobas TaqMan HBV tests for the quantification of hepatitis B virus DNA

This study aimed to standardise an in-house real-time polymerase chain reaction (rtPCR) to allow quantification of hepatitis B virus (HBV) DNA in serum or plasma samples, and to compare this method with two commercial assays, the Cobas Amplicor HBV monitor and the Cobas AmpliPrep/Cobas TaqMan HBV test. Samples from 397 patients from the state of São Paulo were analysed by all three methods. Fifty-two samples were from patients who were human immunodeficiency virus and hepatitis C virus positive, but HBV negative. Genotypes were characterised, and the viral load was measure in each sample. The in-house rtPCR showed an excellent success rate compared with commercial tests; inter-assay and intra-assay coefficients correlated with commercial tests (r = 0.96 and r = 0.913, p < 0.001) and the in-house test showed no genotype-dependent differences in detection and quantification rates. The in-house assay tested in this study could be used for screening and quantifying HBV DNA in order to monitor patients during therapy.

MANICURE/PEDICURE TECHNICIANS: BIOSECURITY KNOWLEDGE AND PRACTICES FOR VIRAL HEPATITIS

Objetivo: Investigar o conhecimento e as práticas de biossegurança para hepatites virais de manicures/pedicures. Métodos: Estudo descritivo, transversal, quantitativo, através de questionário, utilizando instrumento de coleta de dados autoaplicado elaborado pelos pesquisadores, contendo dados da população (sexo, idade, tempo de atuação profissional) e conhecimentos básicos sobre transmissão de hepatite e práticas de biossegurança e higiene. Resultados: Entrevistaram-se 96 manicures/pedicures que atuam no Noroeste do Paraná. A maioria das profissionais já ouviu falar da patologia, mas somente 41,7% (n=40) fizeram o exame para detecção do vírus da hepatite; 38,39% (n=77) relataram como via de transmissão o sangue e 31,8% (n=63), a relação sexual. A reutilização de materiais descartáveis foi relatada por 60,4% (n=58); 55,2% (n=53) realizam esterilização de materiais e 27,1% (n=26) não a realizam. Não ficou evidenciada associação significativa entre tempo de profissão e as variáveis utilizadas: ouviu sobre hepatite (p=0,77025), realização de exames (p=0,035476), reutilização de materiais descartáveis (p=0,42691), lavagem de mãos (p=0,32876), uso de luvas descartáveis (p=0,33752) e esterilização de materiais (p=0,84443). Conclusão: As manicures entrevistadas não conhecem as exigências da Vigilância Sanitária no que concerne à prevenção da transmissão de hepatites.

Original Research Article Humoral and cellular immune responses to modified hepatitis B plasmid DNA vaccine in mice

Purpose: To evaluate the immunogenicity and types of immune response of a quality-controlled modified recombinant hepatitis B surface antigen (HBsAg) plasmid encoding HBsAg in mice. Methods: The characterized plasmid DNA was used in the immunization of Balb/c mice. Three groups of mice were intramuscularly injected with three different concentrations (50, 25 and 10 μg/100 μL) of the modified plasmid. Humoral immune response was monitored by enzyme-linked immunosorbent assay (ELISA), while cellular immune response was investigated by analysis of spleen cytokine profile (TNFα, IFN γ and IL2) as well as CD69 expression level in CD4 and CD8 positive cells. Results: In general, the activated CD4 cells showing intracellular cytokines were higher than CD8 positive population of cells (p < 0.05). These findings indicate that the vaccine induced both a humoral and cellular immunity. Cytokine profile also showed high levels of TNFα, IFN γ and IL2 and CD69 expression in the group of animals immunized at a dose of 10 μg when compared to control group (p < 0.05). Conclusion: A 10 μg dose intramuscular injection of the modified DNA-based vaccine encoding HBsAg in mice induces both high humoral and cellular immune responses.