RESUMEN
The recent data on the genetic variability of the hepatitis B virus and problems of serological ELISA-mediated detection of this virus are discussed.
Asunto(s)
Variación Genética , Virus de la Hepatitis B , Hepatitis B , Ensayo de Inmunoadsorción Enzimática/métodos , Hepatitis B/sangre , Hepatitis B/diagnóstico , Hepatitis B/genética , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/metabolismo , Humanos , Pruebas Serológicas/métodosRESUMEN
AIM: Study heterogeneity ofhepatitis B virus in adult patients with chronic hepatitis B and determination of diagnostic potential of modern test systems with the detection of HBsAg with amino acid substitutions in the main hydrophilic region (MHR). MATERIALS AND METHODS: In 27 hepatitis B virus samples isolated from patients with chronic hepatitis B virus infection living in Vladimir, nucleotide sequence ofgenome region corresponding to preS1/preS2/S genes was determined. RESULTS: In all of the 27 isolates genotype D virus presented by 3 subgenotypes D1, D2, D3 was detected in 18%, 26% and 56% respectively. Based on the distribution of nucleotide substitutions in the compared functional regions of hepatitis B virus (virus entry into the cell coding site (2875 - 2991 n.b.), pre-S2/S promoter region (2994 - 3171 n.b.), 5'-end pre-S2 and S-genes sequences (3172 - 154 n.b. and 155-455 n.b.), MHR (455 - 635 n.b.) and 3'-end S-gene sequence (636 - 835 n.b.), substitutions are mostly concentrated in the promoter region of the S2/S-genes (30.8%). HBsAg serotypes were determined in 24 of 27 cases by using the predicted amino acid sequence, and in 17 cases HBsAg belonged to ayw2 (71%) serotype and in 7 cases - to ayw3 serotype (29%). Amino acid substitutions G145A, M133I, S132T localized in the main hydrophilic region and P217L, S207N, V184A localized in the C-end of the protein C that are connected with diagnostic and vaccine escape were identified in 5 isolates. CONCLUSION: Diagnostic potential of test systems with the detection of HBsAg with known amino acid sequence of the MHR region were studied. Approximately equal potential of 6 test systems to detect HBsAg with amino acid substitutions G145A, M133I and S132T localized in the MHR region were shown.
Asunto(s)
ADN Viral/análisis , Antígenos de Superficie de la Hepatitis B/genética , Virus de la Hepatitis B/genética , Hepatitis B Crónica/diagnóstico , Inmunoensayo , Mutación , Precursores de Proteínas/genética , Adulto , Sustitución de Aminoácidos/inmunología , ADN Viral/biosíntesis , Femenino , Heterogeneidad Genética , Genotipo , Anticuerpos contra la Hepatitis B/análisis , Anticuerpos contra la Hepatitis B/inmunología , Antígenos de Superficie de la Hepatitis B/clasificación , Antígenos de Superficie de la Hepatitis B/inmunología , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/inmunología , Hepatitis B Crónica/inmunología , Humanos , Masculino , Persona de Mediana Edad , Sistemas de Lectura Abierta/inmunología , Regiones Promotoras Genéticas/inmunología , Precursores de Proteínas/clasificación , Precursores de Proteínas/inmunología , Estructura Terciaria de Proteína , Federación de Rusia , Sensibilidad y EspecificidadRESUMEN
AIM: Studies of hepatitis C virus (HCV) genotype and subtype structure in patients with chronic hepatitis C in 3 regions of the Central federal district of Russia. MATERIALS AND METHODS: Hepatitis C virus genotype and subtype structure was determined in patients with chronic HCV infection in Moscow (1993 - 1995 and 2005), Moscow region (2008) and Vladimir region (1993 -1995, 2005-2007). HCV genotype was determined by using A. Widell et al. (1994) technique, PCR (AmpliSens diagnostic kits), Genotype C test system. RESULTS: In all studied regions and during all the time periods the first position in rating belonged to HCV 1b subtype. In 1993 - 1995 and 2005 - 2007 period changes in HCV genotype and subtype structure were registered that consisted of relative weight of 1b subtype decrease and 3a subtype increase. Subtype 1b in females with chronic hepatitis C was registered more often than in males. In Vladimir region 3a subtype in males was detected more often than in females. In males older than 30 years the first rating position belongs to 1b subtype and in males younger than 30 years--subtype 3a. In females older than 30 years in Moscow region and Vladimir region, as well as in females younger than 30 years in Vladimir region subtype 1b was detected more often, while in Moscow region HCV subtypes 1b and 3a were detected with the same rate of 47.6%. CONCLUSION: Currently there is an urgent need to include mandatory monitoring of hepatitis C virus genetic variants into the system of hepatitis C epidemiologic control in Russia. This approach will allow for a significant increase in quality of hepatitis C serological diagnostics, and can be used in the prognosis of evolution of the epidemic process of this disease.
Asunto(s)
Hepacivirus/clasificación , Hepacivirus/genética , Hepatitis C Crónica/epidemiología , Hepatitis C Crónica/virología , Factores de Edad , Femenino , Genotipo , Hepacivirus/aislamiento & purificación , Humanos , Masculino , Datos de Secuencia Molecular , Moscú/epidemiología , ARN Viral/análisis , ARN Viral/genética , Federación de Rusia/epidemiologíaRESUMEN
The diagnostic capacities of 4 commercial test systems were comparatively estimated for the detection of HBsAg, by applying a panel of samples with the established amino acid sequence of the "a" determinant of HBsAg. The Roche Elecsys HBsAg test system demonstrated the highest sensitivity - the maximum HBsAg concentrations were found in 19 of 31 cases. Escape mutations in the major hydrophilic region (MHR) of HBsAG (P120S, M133T) were responsible for differences in the sensitivity of 4 test systems by 10- to 40-fold. There were also samples that showed differences in the diagnostic capacities of the test systems to detect HBsAg, but without amino acid replacements in the area of the "a" determinant, which seems to be associated with amino acid replacements in other regions of HBsAg.
Asunto(s)
Antígenos de Superficie de la Hepatitis B/aislamiento & purificación , Virus de la Hepatitis B/aislamiento & purificación , Hepatitis B Crónica/diagnóstico , Juego de Reactivos para Diagnóstico , Sustitución de Aminoácidos/genética , Sustitución de Aminoácidos/inmunología , Genes Virales/genética , Antígenos de Superficie de la Hepatitis B/genética , Antígenos de Superficie de la Hepatitis B/inmunología , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/inmunología , Humanos , Mutación , Sensibilidad y EspecificidadRESUMEN
The OOO "Research-and-Production Association "Diagnostic Systems" has developed a "DC-EIA-HIV-AT/AG-SPECTRUM" screening enzyme immunoassay system designed to detect separately antibodies to certain HIV-1 and HIV-2 proteins, as well as antigen p24. The determination of antibodies of all classes and the marker of early-stage infection antigen p24 with a high (5 pg/ml) sensitivity substantially reduces the number of void results obtained in the use of immunoblots. The developed "DC-EIA-HIV-AT/AG-SPECTRUM" plate system is an effective tool to support positive screening results and may be used at the final stage of laboratory diagnosis of HIV infection.