RESUMEN
Current data on molecular biology and immunology of the proteins of hepatitis B viral capsid encoded by the preS-region of HBV genome are reviewed. Main attention is paid to study of the immune properties of the capsid proteins, to search of immune dominant epitopes encoded in preS-sequences. The medical and biological significance of the research is shown as exemplified by search of preS-antigens and anti-preS-antibodies in serum from patients suffering hepatitis B. The use of preS-sequences as components of vaccine preparations is discussed.
Asunto(s)
Virus de la Hepatitis B/genética , Proteínas del Envoltorio Viral/genética , Anticuerpos Antivirales , Genoma Viral , Humanos , Epítopos Inmunodominantes , Proteínas del Envoltorio Viral/inmunologíaRESUMEN
Insertion of 48 amino acid long sequence of envelope protein gp51 of bovine leukemia virus (BLV), located from position 56 till 103 of mature protein, into Pro144 position of hepatitis B core antigen (HBcAg) leads to the formation of chimeric capsids. These capsids preserve morphology of intact HBcAg but expose on their outer surface BLV epitopes which are localised in the inserted gp51 fragment and responsible for the recognition of chimeras by monoclonal anti-gp51 antibodies MAK14. The anti-genicity of gp51 epitopes within chimeric capsids is not disturbed after shortening of C terminal part of inserted gp51 fragment by deletion of amino acids 73-103. The resulting chimeras show the same capsid-forming ability as well as HBcAg and gp51 antigenic properties.
Asunto(s)
Cápside/inmunología , Epítopos/inmunología , Antígenos del Núcleo de la Hepatitis B/inmunología , Virus de la Leucemia Bovina/inmunología , Proteínas del Envoltorio Viral/inmunología , Secuencia de Aminoácidos , Anticuerpos Monoclonales/inmunología , Western Blotting , Cápside/ultraestructura , Quimera , Epítopos/genética , Inmunodifusión , Microscopía Electrónica , Linfocitos T/inmunología , Proteínas del Envoltorio Viral/genéticaAsunto(s)
Cápside/genética , Genes Virales , Antígenos del Núcleo de la Hepatitis B/genética , Péptidos/genética , Anticuerpos Monoclonales , Cápside/inmunología , Clonación Molecular , Ensayo de Inmunoadsorción Enzimática , Escherichia coli/genética , Expresión Génica , Antígenos del Núcleo de la Hepatitis B/química , Espectroscopía de Resonancia Magnética , Péptidos/química , Péptidos/inmunología , Recombinación GenéticaRESUMEN
A set of recombinant plasmids with a gene encoding surface antigen of hepatitis B virus (HBsAg) is constructed. The plasmids were transfected by DEAE-dextran method into different lines of cultured cells and transient expression of the HBsAg gene was studied. The results indicate that: transcriptional enhancer of hepatitis B virus situated downstream from HBsAg gene is active in green monkey kidney cells (CVI), promoter of 5 LTR of bovine leukemia virus is trans-activated in the goat or calf cells infected with BLV. The results are discussed in the light of hypothesis on the role of transcriptional enhancers in determination of tissue-specificity of hepatitis B virus.