title: Humoral immune response in mice against a circulating antigen induced by adenoviral transfer is strictly dependent on expression in antigen-presenting cells.
abstract: Adenoviral transfer of human apo A-I in Balb/c mice induces a strong humoral immune response against the transgene product when expression is driven from the ubiquitously active CMV promoter but induces no immune response when driven by the hepatocyte-specific 256-base pair apo A-I promoter. Here the hypothesis was tested, which is that the humoral immune response against the circulating transgene product correlates with its expression in antigen-presenting cells. No humoral immune response was observed after adenoviral transfer of vectors with human apo A-I expression driven by the hepatocyte-specific apo C-II or 1.5-kilobase (kb) human alpha(1)-antitrypsin promoter, but antibodies were induced after transfer with vectors driven by the ubiquitously active U1b promoter and the murine MHCII E beta promoter. A strict correlation was observed between antigen expression in the spleen and the occurrence of an immune response. Coinjection of the 1.5-kb human alpha(1)-antitrypsin and the murine MHCII E beta promoter-driven vectors resulted in a very short-lived humoral immune response against human apo A-I, suggesting that the time course of human apo A-I expression is a critical determinant of the development of tolerance for human apo A-I. High titers of antibodies against human apo A-I after subcutaneous gene transfer with the MHCII E beta promoter-driven vector underscore the potential of this promoter for vaccination purposes. In conclusion, humoral immune response in mice against a circulating antigen induced by adenoviral transfer is strictly dependent on expression in antigen-presenting cells.
authors.affiliation: Center for Molecular and Vascular Biology, Department for Molecular and Cardiovascular Research, Leuven, Belgium. bart.degeest@med.kuleuven.ac.be
authors.forename: Bart R
authors.initials: BR
authors.lastname: De Geest
authors.forename: Sophie A
authors.initials: SA
authors.lastname: Van Linthout
authors.forename: Désiré
authors.initials: D
authors.lastname: Collen
mesh_terms: D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D000910:Antibodies, Heterophile / Q000097:blood; D000917:Antibody Formation; D000938:Antigen-Presenting Cells / Q000276:immunology / Q000378:metabolism*; D015478:Antigens, Heterophile / Q000097:blood / Q000235:genetics / Q000276:immunology*; D016632:Apolipoprotein A-I / Q000097:blood / Q000235:genetics / Q000276:immunology*; D018014:Gene Transfer Techniques / Q000592:standards*; D005822:Genetic Vectors; D006801:Humans; D007108:Immune Tolerance; D051379:Mice; D008807:Mice, Inbred BALB C; D008822:Mice, Transgenic; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000032:analysis; D013154:Spleen / Q000166:cytology / Q000276:immunology / Q000378:metabolism
chemical_list: D000910:Antibodies, Heterophile; D015478:Antigens, Heterophile; D016632:Apolipoprotein A-I; D012333:RNA, Messenger