title: Tumor immunotherapy by converting tumor cells to MHC class II-positive, Ii protein-negative phenotype.
abstract: A potent antitumor CD4(+) T-helper cell immune response is created by inducing tumor cells in vivo to a MHC class II(+)/Ii(- )phenotype. MHC class II and Ii molecules were induced in tumor cells in situ following tumor injection of a plasmid containing the gene for the MHC class II transactivator (CIITA). Ii protein was suppressed by the antisense effect of an Ii-reverse gene construct (Ii-RGC) in the same or another co-injected plasmid. The MHC class II(+)/Ii(- )phenotype of the tumor cells was confirmed by FACS analysis of cells transfected in vitro and by immunostaining of tumor nodules transfected by injections in vivo. Subcutaneous Renca tumors in BALB/c mice were treated by intratumoral injection with CIITA and Ii-RGC, in combination with a subtherapeutic dose of IL-2, to up-regulate the activation of T cells. Significant tumor shrinkage and decrease in rates of progression of established Renca tumors were seen in the groups injected with Ii-RGC, compared with groups in which only IL-2 plus empty plasmid controls were injected. Our method provides an effective immunotherapy warranting further development for human cancers.
authors.affiliation: Antigen Express, 100 Barber Avenue, Worcester, MA 01606, USA.
authors.forename: Xueqing
authors.initials: X
authors.lastname: Lu
authors.forename: Nikoletta L
authors.initials: NL
authors.lastname: Kallinteris
authors.forename: Jizhi
authors.initials: J
authors.lastname: Li
authors.forename: Shuzhen
authors.initials: S
authors.lastname: Wu
authors.forename: Yu
authors.initials: Y
authors.lastname: Li
authors.forename: Zhong
authors.initials: Z
authors.lastname: Jiang
authors.forename: Gilda G
authors.initials: GG
authors.lastname: Hillman
authors.forename: Joseph V
authors.initials: JV
authors.lastname: Gulfo
authors.forename: Robert E
authors.initials: RE
authors.lastname: Humphreys
authors.forename: Minzhen
authors.initials: M
authors.lastname: Xu
mesh_terms: D000818:Animals; D000951:Antigens, Neoplasm / Q000235:genetics; D002292:Carcinoma, Renal Cell / Q000235:genetics / Q000276:immunology / Q000473:pathology; D016373:DNA, Antisense / Q000008:administration & dosage*; D005802:Genes, MHC Class II; D015316:Genetic Therapy; D005822:Genetic Vectors / Q000008:administration & dosage; D000949:Histocompatibility Antigens Class II / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D016130:Immunophenotyping; D007167:Immunotherapy; D007279:Injections, Subcutaneous; D007376:Interleukin-2 / Q000494:pharmacology; D007680:Kidney Neoplasms / Q000235:genetics / Q000276:immunology / Q000473:pathology; D051379:Mice; D008807:Mice, Inbred BALB C; D009374:Neoplasms, Experimental / Q000276:immunology / Q000473:pathology / Q000628:therapy*; D009687:Nuclear Proteins; D010957:Plasmids; D013601:T-Lymphocytes / Q000276:immunology / Q000378:metabolism; D015534:Trans-Activators / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D014161:Transduction, Genetic / Q000379:methods; D014162:Transfection; D014407:Tumor Cells, Cultured
chemical_list: D000951:Antigens, Neoplasm; D016373:DNA, Antisense; D000949:Histocompatibility Antigens Class II; D007376:Interleukin-2; C083728:MHC class II transactivator protein; D009687:Nuclear Proteins; D015534:Trans-Activators