title: Intramuscular co-injection of naked DNA encoding HBV core antigen and Flt3 ligand suppresses anti-HBc antibody response.
abstract: Flt3 ligand, a recently described growth factor affecting early hematopoietic progenitor cells, can also support the expansion of dendritic cells secreting IL-12. Its potential use in a clinical setting has been suggested. Here, we studied the effect of in situ delivery of Flt3 ligand plasmid (FL) on the antibody response induced by DNA vaccine encoding wild-type hepatitis B virus core antigen (HBc/w). Intramuscular injection of FL increased the expression of DEC205 and the size of splenocytes, and immunization with HBc/w or HBc/w-transfected EL-4 cells induced strong anti-HBc antibody responses in mice. However, intramuscular injection of FL with HBc/w significantly suppressed HBc/w-induced antibody response in a dose-dependent manner. Suppression of immune response by FL injection was the most prominent when FL and HBc/w were co-injected at the same time and the same site. These results suggest that FL may inhibit humoral response induced by DNA-type vaccination, and DC locally expanded by FL may not have proper functions for induction of humoral response.
authors.affiliation: Department of Immunology, School of Medicine, Keimyung University, 194 Dong-San Dong, Jung-Gu, Taegu 700-712, Republic of Korea.
authors.forename: Taeg Kyu
authors.initials: TK
authors.lastname: Kwon
authors.forename: Jong Wook
authors.initials: JW
authors.lastname: Park
mesh_terms: D000818:Animals; D002460:Cell Line; D006510:Hepatitis B Antibodies / Q000096:biosynthesis*; D006512:Hepatitis B Core Antigens / Q000032:analysis / Q000235:genetics* / Q000276:immunology*; D017325:Hepatitis B Vaccines / Q000008:administration & dosage / Q000276:immunology*; D007273:Injections, Intramuscular; D007700:Kinetics; D008565:Membrane Proteins / Q000032:analysis / Q000235:genetics*; D051379:Mice; D019444:Vaccines, DNA / Q000008:administration & dosage / Q000276:immunology
chemical_list: D006510:Hepatitis B Antibodies; D006512:Hepatitis B Core Antigens; D017325:Hepatitis B Vaccines; D008565:Membrane Proteins; D019444:Vaccines, DNA; C084881:flt3 ligand protein