Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019163 (hepatitis B)
 38,309 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An enzyme-linked immunosorbent assay (ELISA) for anti-pre-S2 antibodies was developed by the use of both recombinant yeast-derived S and M (pre-S2 + S) protein particles as antigens. By this ELISA was determined the amount of both human and chimpanzee anti-pre-S2 antibodies produced by a new type of yeast-derived hepatitis B (HB) vaccine (TGP-943, subtype adr), which consists of modified M protein particles. In seven randomly selected human individuals who were vaccinated intramuscularly with 10 micrograms (as a protein) TGP-943 three times (0, 4th and 24th week), a detectable level of anti-pre-S2 antibodies was found to be rapidly elicited at 4th or 8th week after the first vaccination. The protective level of anti-pre-S2 antibodies in humans was tentatively assessed by comparing the anti-pre-S2 antibody titres in the vaccinated human individuals with that in chimpanzees which produced only anti-pre-S2 antibodies to tolerate well against the challenge by 1000 chimpanzee infectious units of HBV (subtype ayw). From this assessment, it was speculated that all human individuals tested had already acquired the protective level of anti-pre-S2 antibodies at 4th or 8th week after the first vaccination with TGP-943.
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PMID:Induction of protection level of anti-pre-S2 antibodies in humans immunized with a novel hepatitis B vaccine consisting of M (pre-S2 + S) protein particles (a third generation vaccine). 182 18

The protective efficacy of a new type of yeast-derived hepatitis B (HB) vaccine (TGP-943, subtype adr), which was formulated from modified M (pre-S2 + S; P31) protein (M-P31c) particles, was investigated in chimpanzees. Animals were injected intramuscularly three times at 4-week intervals with doses of 10 or 40 micrograms (as a protein) of TGP-943. There were no significant differences in the immunogenicity of 10 micrograms compared to that of 40 micrograms of TGP-943 in terms of anti-S antibody response, while the induction and persistence of anti-pre-S2 antibodies seemed dose-related. Chimpanzees, vaccinated with 40 micrograms of TGP-943, produced anti-pre-S2 antibodies 2 weeks after the first injection, which appeared earlier than anti-HBs (S) antibodies. A maximum level of the anti-pre-S2 antibodies was reached 2 weeks after the second injection. Apart from immunization with TGP-943, chimpanzees injected with denatured TGP-943, consisting of 10 micrograms (as a protein) of non-particulate M-P31c antigen, produced anti-pre-S2 antibodies with a non-protecting level of anti-S antibodies (less than 10 mIU ml-1). Five weeks after the third injection, all animals were challenged intravenously with 1000 chimpanzee infectious units of HBV subtype (ayw) and were protected as confirmed by normal serological markers, no signs of infection in the sera and liver biopsies, and no detection of HBV-DNA by PCR method. No side effects from inoculation with TGP-943 or denatured TGP-943 were also encountered in any animals.
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PMID:Protective efficacy of a novel hepatitis B vaccine consisting of M (pre-S2 + S) protein particles (a third generation vaccine). 236 98

Genetically modified M (pre-S2+S; P31) protein (M-P31c) particles were formulated into a vaccine (TGP-943) through adsorption on to an alum adjuvant. The immunogenicity of this vaccine was investigated using guinea-pigs and various kinds of mice. In terms of anti-HBs(S) response, TGP-943 was found to be as immunogenic as the control plasma-derived vaccine (PDV) and yeast-derived S vaccine (YDSV) in Balb/c mice. TGP-943 induced anti-S antibodies even in S low-responder mice. In addition to the anti-S antibodies, TGP-943 was shown to elicit anti-pre-S2 antibodies dose-dependently, and the anti-pre-S2 antibodies were maintained at a high level after immunization with a high dose of TGP-943. The antibody response to pre-S2 had a tendency to appear earlier than that to S. M-P31c particles induced in vitro proliferation of TGP-943-primed lymph node cells, indicating that TGP-943 is more immunogenic than conventional vaccines in terms of T-cell levels. These results suggest that TGP-943 would be a promising candidate for a third generation hepatitis B vaccine.
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PMID:Immunogenicity of a new type of yeast-derived hepatitis B vaccine consisting of M (pre-S2 + S) protein particles. 253 13

A recombinant yeast-derived pre-S2 + S-containing hepatitis B vaccine (TGP-943) was clinically evaluated through three phases of testing in a total of 2137 volunteers. We observed the immunogenic purity of TGP-943 (phase 1), the inter-lot reproducibility of both safety and immunogenicity (phase 2), no significant side-effects, a high capability of inducing both anti-HBs and anti-pre-S2 antibodies (phases 1, 2 and 3), and an ability to induce seroconversion in the majority of vaccines who had been non-responsive to conventional hepatitis B vaccines (phases 2 and 3). In conclusion, TGP-943 is a safe and tolerable vaccine, with special merits: the ability to induce an early anti-pre-S2 response that circumvents the problem of delayed appearance of anti-HBs, and efficacy in non-responders to previous vaccination.
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PMID:Safety and efficacy of a recombinant yeast-derived pre-S2 + S-containing hepatitis B vaccine (TGP-943): phase 1, 2 and 3 clinical testing. 799 18

A Western blot assay was standardized to evaluate the antigenic reactivity of hepatitis B virus (HBV) strains circulating in Brazilian population with antibodies raised against recombinant hepatitis B (HB) vaccines. In this assay, HBV envelope proteins from infected human blood were detected by antibodies from rabbits immunized with either of two recombinant vaccines. These were Engerix B (Smith Kline Beecham, Belgium) containing exclusively S protein particles and TGP-943 (Takeda Chemical Industries, Japan) containing M protein particles. Forty-seven serum samples, presenting HB surface antigen. (HBsAg) reverse passive haemagglutination assay (RPHA) titers ranging from 1:32 to > or =1:4096 after HBV particles concentration, were tested. Twenty-seven samples were from acute hepatitis cases and 20 were from chronic cases (11 from cirrhotic patients and 9 from asymptomatic carriers). Four HBV serotypes, adw2, adw4, ayw2 and ayw3, were identified in these samples. Infectivity of these sera was evaluated by HBV DNA detection by polymerase chain reaction (PCR). HBV DNA was present in 62% of samples from acute cases and in all samples from chronic cases. Despite the differences between serotypes, genotypes, forms of infection, and infectivity of the samples, antibodies against both vaccines reacted with HBV envelope proteins from all but one sample. In one sample from cirrhotic patient, only a small protein of unexpected size reacted with TGP-943 antibodies.
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PMID:Western blot analysis of the reactivity between envelope proteins of hepatitis B viruses from Brazilian carriers and antibodies raised against recombinant hepatitis B vaccines. 917 52