title: Low responsiveness of hepatitis B virus-transgenic mice in antibody response to T-cell-dependent antigen: defect in antigen-presenting activity of dendritic cells.
abstract: The experiments presented here were performed to evaluate immune responsiveness of hepatitis B virus (HBV)-transgenic mice (transgenic mice), as a model of HBV-carrier state to a T-cell-dependent antigen, keyhole limpet haemocyanin (KLH). The transgenic mice which were completely unresponsive to hepatitis B surface antigen (HBsAg), responded poorly to KLH. The levels of anti-KLH antibodies (Ab) produced in vivo were significantly lower in transgenic mice compared with the normal control mice at respective immunizing doses of KLH. In addition, a little or no anti-KLH Ab production was detected in culture supernatants of KLH-primed transgenic mice spleen cells. KLH-primed T cells from normal and transgenic mice induced anti-KLH Ab production from transgenic B cells in the presence of antigen-presenting spleen adherent cells (SAC) from normal mice, but not those from transgenic mice. Depletion of dendritic cells from normal mice-derived SAC completely abrogated the anti-KLH Ab response in transgenic spleen cell culture and their addition to the culture restored the response. Low efficiency of transgenic dendritic cells was demonstrated in sodium periodate (NaIO4)-induced non-specific and allogenic antigen-induced T-cell proliferation. Finally, cytofluorometric analyses showed a reduced Ia antigen expression on transgenic dendritic cells. These results indicate that low responsiveness of transgenic mice in specific-antibody response is not due to functional defects in T cells or B cells but rather to a defect of antigen-presenting activity of dendritic cells.
authors: Third Dept. of Internal Medicine, Ehime University School of Medicine, Japan.
authors: S M
authors: SM
authors: Akbar
authors: M
authors: M
authors: Onji
authors: K
authors: K
authors: Inaba
authors: K
authors: K
authors: Yamamura
authors: Y
authors: Y
authors: Ohta
mesh_terms: D000818:Animals; D000917:Antibody Formation; D000941:Antigens / Q000276:immunology*; D002353:Carrier State / Q000276:immunology*; D002478:Cells, Cultured; D003713:Dendritic Cells / Q000276:immunology*; D006433:Hemocyanins / Q000276:immunology*; D006509:Hepatitis B / Q000276:immunology*; D000949:Histocompatibility Antigens Class II / Q000032:analysis; D007959:Lymphocyte Culture Test, Mixed; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D013154:Spleen / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D000941:Antigens; D000949:Histocompatibility Antigens Class II; D006433:Hemocyanins; C032808:keyhole-limpet hemocyanin