title: Intradermal delivery of IL-12 naked DNA induces systemic NK cell activation and Th1 response in vivo that is independent of endogenous IL-12 production.
abstract: In this study four murine IL-12 naked DNA expression plasmids (pIL-12), containing both the p35 and p40 subunits, were shown to induce systemic biological effects in vivo after intradermal injection. Three of the four IL-12 expression vectors augmented NK activity and induced expression of the IFN-gamma and IFN-gamma-inducible Mig genes. Both IL-12 p70 heterodimer and IFN-gamma proteins were documented in the serum within 24 h after intradermal injection of the pIL-12o- plasmid, which also induced the highest level of NK activity in the spleen and liver among the IL-12 constructs. Interestingly, both p40 mRNA expression at the injection site and serum protein levels followed a biphasic pattern of expression, with peaks on days 1 and 5. Subsequent studies revealed that the ability of intradermally injected pIL-12o- to augment NK lytic activity was prevented by administration of a neutralizing anti-IL-12 mAb. Finally, injection of the pIL-12o- into BALB/c IL-12 p40-/- mice also resulted in a biphasic pattern of IL-12 p70 appearance in the serum, and induced IFN-gamma protein and activated NK lytic activity in liver and spleen. These results demonstrate that injection of delivered naked DNA encoding the IL-12 gene mediates the biphasic systemic production of IL-12-inducible genes and augments the cytotoxic function of NK cells in lymphoid and parenchymal organs as a direct result of transgene expression. The results also suggest that these naked DNA plasmids may be useful adjuvants for vaccines against infectious and neoplastic diseases.
authors.affiliation: Laboratory of Experimental Immunology, Division of Basic Sciences, National Cancer Institute-Frederick Cancer Research and Development Center, MD 21702-1201, USA.
authors.forename: M
authors.initials: M
authors.lastname: Watanabe
authors.forename: R G
authors.initials: RG
authors.lastname: Fenton
authors.forename: J M
authors.initials: JM
authors.lastname: Wigginton
authors.forename: K L
authors.initials: KL
authors.lastname: McCormick
authors.forename: K M
authors.initials: KM
authors.lastname: Volker
authors.forename: W E
authors.initials: WE
authors.lastname: Fogler
authors.forename: P G
authors.initials: PG
authors.lastname: Roessler
authors.forename: R H
authors.initials: RH
authors.lastname: Wiltrout
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage; D000818:Animals; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D054370:Chemokine CXCL9; D019743:Chemokines, CXC / Q000096:biosynthesis / Q000235:genetics; D003587:Cytomegalovirus / Q000235:genetics; D003602:Cytotoxicity, Immunologic / Q000235:genetics / Q000276:immunology; D004279:DNA, Viral / Q000008:administration & dosage*; D005260:Female; D015967:Gene Expression Regulation, Viral / Q000276:immunology; D007166:Immunosuppressive Agents / Q000494:pharmacology; D007271:Injections, Intradermal; D036341:Intercellular Signaling Peptides and Proteins; D007371:Interferon-gamma / Q000096:biosynthesis / Q000097:blood / Q000235:genetics; D018664:Interleukin-12 / Q000008:administration & dosage / Q000096:biosynthesis* / Q000235:genetics* / Q000276:immunology; D007694:Killer Cells, Natural / Q000276:immunology*; D007700:Kinetics; D008213:Lymphocyte Activation / Q000235:genetics*; D051379:Mice; D008807:Mice, Inbred BALB C; D018345:Mice, Knockout; D010957:Plasmids / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology; D013154:Spleen / Q000276:immunology / Q000378:metabolism; D018417:Th1 Cells / Q000378:metabolism*; D001616:beta-Galactosidase / Q000008:administration & dosage / Q000096:biosynthesis / Q000235:genetics
chemical_list: D000276:Adjuvants, Immunologic; D000911:Antibodies, Monoclonal; C080810:CXCL9 protein, human; D054370:Chemokine CXCL9; D019743:Chemokines, CXC; D004279:DNA, Viral; D007166:Immunosuppressive Agents; D036341:Intercellular Signaling Peptides and Proteins; D018664:Interleukin-12; D007371:Interferon-gamma; D001616:beta-Galactosidase