Intramuscular co-injection of naked DNA encoding HBV core antigen and Flt3 ligand suppresses anti-HBc antibody response.
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.
Kwon
Taeg Kyu
TK
Department of Immunology, School of Medicine, Keimyung University, 194 Dong-San Dong, Jung-Gu, Taegu 700-712, Republic of Korea.
Park
Jong Wook
JW
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
D006510:Hepatitis B Antibodies; D006512:Hepatitis B Core Antigens; D017325:Hepatitis B Vaccines; D008565:Membrane Proteins; D019444:Vaccines, DNA; C084881:flt3 ligand protein