[Rejection of non-immunogenic tumor cells transfected with costimulatory molecule B7 after treatment with IFN-gamma in vitro].
OBJECTIVE
To explore immuno-gene-therapy of non-immunogenic tumor.


METHODS
Non-immurogenic tumor cells B16 were transfected with B7-1 gene. The B7-1 gene transfected B16 cells (B7+ B16) were treated with recombinant murine interferon-gamma (rmIFN-gamma) in vitro, and then inoculated to C57BL/6 mice.


RESULTS
While B7+ B16 cells grew progressively in syngeneic mice, tumorigenicty was significantly reduced when B7+ B16 cells were treated with rmIFN-gamma before inoculation to mice. Flow cytometric analysis of the rmIFN-gamma treated B7+ B16 cells showed significant up-regulation of MHC class I expression.


CONCLUSIONS
For non-immunogenic tumor if the expressions of MHC class I molecules is low, providing co-stimulatory molecule B7 is not enough to reduce tumorigenicity. The B7-1 gene transfected B16 cells become non-tumorigenic or weakly tumorigenic when their MHC class I is up-regulated.
Cancer Institute(Hospital), Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing.
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Zheng
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Zhang
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Wang
D000818:Animals; D018122:B7-1 Antigen / Q000096:biosynthesis*; D015870:Gene Expression; D005805:Genes, MHC Class I; D007371:Interferon-gamma / Q000494:pharmacology*; D008546:Melanoma, Experimental / Q000235:genetics* / Q000276:immunology / Q000473:pathology; D051379:Mice; D008810:Mice, Inbred C57BL; D011994:Recombinant Proteins; D014162:Transfection; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000276:immunology
D018122:B7-1 Antigen; D011994:Recombinant Proteins; D007371:Interferon-gamma