Specific vaccine therapy in chronic hepatitis B: induction of T cell proliferative responses specific for envelope antigens.
In a pilot study, it was established that specific therapy by standard anti-hepatitis B virus (HBV) vaccination may be effective in reducing HBV replication and canceling the immune tolerance to hepatitis B surface antigen (HBsAg) particles in about 50% of persons with chronic active HBV replication. In the present study, the vaccine-induced immune responses were analyzed during an ongoing controlled multicenter vaccine trial. Vaccination elicited peripheral blood mononuclear cell proliferative responses specific for envelope antigen in 7 of 27 subjects given HBsAg. The responses induced by the vaccines were mediated by CD4+ T lymphocytes, and at least three different epitopes were recognized. HBV-specific CD4+ T lymphocytes produced high levels of interferon-gamma [corrected] and belonged to a T helper 1 subset. Reduction of serum HBV DNA in some of these persons suggests that induction of CD4+ T cell responses could be important in controlling viremia during vaccine therapy of chronic HBV carriers.
Couillin
I
I
Unité de Recombinaison et Expression Génétique, INSERM U163, Institut Pasteur, 75724 Paris Cédex 15, France.
Pol
S
S
Mancini
M
M
Driss
F
F
Bréchot
C
C
Tiollais
P
P
Michel
M L
ML
D000939:Epitopes; D006514:Hepatitis B Surface Antigens / Q000276:immunology*; D017325:Hepatitis B Vaccines / Q000276:immunology / Q000627:therapeutic use*; D006513:Hepatitis B e Antigens / Q000276:immunology; D019694:Hepatitis B, Chronic / Q000276:immunology / Q000628:therapy*; D006801:Humans; D016898:Interferon-alpha / Q000096:biosynthesis; D007371:Interferon-gamma / Q000096:biosynthesis; D008213:Lymphocyte Activation; D010865:Pilot Projects; D013601:T-Lymphocytes / Q000276:immunology*; D018417:Th1 Cells / Q000276:immunology; D014611:Vaccination; D014614:Vaccines, Synthetic / Q000276:immunology / Q000627:therapeutic use; D014779:Virus Replication / Q000187:drug effects
D000939:Epitopes; C075656:GenHevac B Pasteur; D006514:Hepatitis B Surface Antigens; D017325:Hepatitis B Vaccines; D006513:Hepatitis B e Antigens; D016898:Interferon-alpha; C075655:Recombivax HB; D014614:Vaccines, Synthetic; D007371:Interferon-gamma