title: [A novel experimental approach to immunotherapy against malignant brain tumor with the mouse IFN-gamma gene transfer].
abstract: To investigate the effect of interferon-gamma (IFN-gamma) on the immunotherapy, we used the autocrinically stimulated system in which a mouse IFN-gamma cDNA was transferred by infection with a chimeric retrovirus containing the IFN-gamma gene. First, we established a tumor specific CTL clone (E-4) against 203-glioma cells (a 20-methylcholanthrene induced mouse ependymoblastoma line of C57BL/6 mouse origin), and then transferred murine IFN-gamma cDNA into E-4 by using retroviral vector (pSVX(Mu gamma delta A]. Out of five gene-transferred subclones, E gamma-4, E gamma-5, E gamma-6, E gamma-7 and E gamma-9, two subclones (E gamma-6 and E gamma-9) constitutively produced 8- to 10-fold amounts of IFN-gamma as compared with the parental E-4. Moreover, these two subclones exhibited two to three times higher killing activity against 203-glioma than the parental cells. The enhancement of the killing activities was abrogated by an adequate addition of anti-IFN-gamma antibody. No alteration was seen after the gene transfer in cell surface phenotypes, Thy-1+, Lyt-1-, Lyt-2+3+ and asialo-GM1-. Fluorescence-activated cell sorter (FACS) analysis showed that the surface expression of major histocompatibility complex (MHC) Class I antigen, H-2Kb, of parental E-4 was augmented remarkably, and it was not altered by the IFN-gamma gene transfer, but the Class II antigen, I-Ab, was slightly enhanced on the two IFN-gamma-producing sublines. Since it is considered that in the vicinity of the constitutively IFN-gamma-producing CTL cells, tumor cells are exposed to a high concentration of IFN-gamma and may be stimulated to induce or enhance the expression of surface antigens including MHC antigens as well as tumor associated antigens in relation to immune recognition. The 203-glioma cells pretreated with IFN-gamma were more efficiently killed by both the parental E-4 and the gene-transferred sublines. It was thus suggested that the specific tumor killing activity of the gene-transferred CTLs was augmented by the constitutive production of IFN-gamma derived from the exogenous gene. As the next step, a mouse IFN-gamma cDNA was transferred into a neuroblastoma line C1300 of A/JAx mouse origin. Two infected subclones C gamma 3 and C gamma 22, were obtained as a low and a high producers, respectively. Both IFN-gamma gene transferred cells remained unchanged as regards in vitro cell growth, morphological appearance and differentiation antigen expression such as neurofilaments after the IFN-gamma gene transfer. On the other hand, expression of MHC Class I antigens of both subcloned lines was extremely augmented at the surface expression level as well as at the transcription level, re
authors.forename: K
authors.initials: K
authors.lastname: Nishihara
mesh_terms: D000818:Animals; D001932:Brain Neoplasms / Q000235:genetics / Q000628:therapy*; D005069:Evaluation Studies as Topic; D015395:Histocompatibility Antigens Class I / Q000235:genetics; D007167:Immunotherapy / Q000379:methods*; D007371:Interferon-gamma / Q000235:genetics*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009447:Neuroblastoma / Q000235:genetics / Q000628:therapy; D014162:Transfection
chemical_list: D015395:Histocompatibility Antigens Class I; D007371:Interferon-gamma