[GM-CSF gene-modified dendritic cell vaccine enhances antitumor immunity in vitro].
OBJECTIVE
To investigate if granulocyte-macrophage colony stimulating factor (GM-CSF) gene-modified dendritic cells (DC) enhance antitumor immunity in vitro.


METHODS
Mice were injected with chemokine ligand 3 (CCL3) via the tail vein. Fresh B220(-)CD11c(+) cells were sorted from the peripheral blood mononuclear cells (PBMCs) and cultured into DCs by cytokines.DCs were transfected with AdGM-CSF gene at different ratios of multiplicity of infection (MOI) to determine the optimal gene transfection conditions, and the expression of GM-CSF was detected after transfection. The variation of GM-CSF gene-modifiedDCs were analyzed by morphological examination, phenotype analysis, and mixed lymphocyte reaction (MLR).DCs were loaded with gastric cancer antigen obtained by freezing and thawing method. The killing effect of DCs vaccine-stimulated T lymphocytes on gastric cancer cells was assessed by MTT assay. INF-gamma production was determined with the INF-gamma ELISA kit.


RESULTS
B220(-)CD11c(+) cells increased obviously after CCL3 injection. The ELISA results showed that after GM-CSF gene modification, DCs could produce high level of GM-CSF. When DCs were transfected with AdGM-CSF gene at MOI equal to 100, the GM-CSF level in culture supernatants reached saturation [(130.00 +/- 12.61) pg/ml]. After GM-CSF gene-modification, DCs tend to be more maturated as detected by morphological observation and phenotype analysis. At the same time, the capacity of activating the proliferation of allogeneic T lymphocytes was enhanced greatly. T lymphocytes stimulated by DCs transfected with GM-CSF gene showed a specific killing effect on gastric carcinoma cells and produced high level of INF-gamma [(1245.00 +/- 13.75) pg/ml].


CONCLUSIONS
After GM-CSF gene modification, DCs can produce high level of GM-CSF, which tend to be more maturated, and the capacity of activating the proliferation of allogeneic T lymphocytes is enhanced greatly. GM-CSF gene modified DCs can induce specific CTL to target tumor cells in vitro.
He
Song-Bing
SB
Department of General Surgery, the First Affiliated Hospital of Soochow University, Suzhou 215006, China. hesongbing2@yahoo.com.cn
Sun
Kang
K
Wang
Liang
L
Li
De-Chun
DC
Zhang
Yan-Yun
YY
D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D018122:B7-1 Antigen / Q000378:metabolism; D051940:B7-2 Antigen / Q000378:metabolism; D019013:CD40 Antigens / Q000378:metabolism; D019496:Cancer Vaccines / Q000276:immunology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D003602:Cytotoxicity, Immunologic; D003713:Dendritic Cells / Q000166:cytology / Q000276:immunology* / Q000378:metabolism; D005260:Female; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000235:genetics / Q000378:metabolism*; D000949:Histocompatibility Antigens Class II / Q000378:metabolism; D007371:Interferon-gamma / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D011994:Recombinant Proteins; D013274:Stomach Neoplasms / Q000276:immunology / Q000378:metabolism / Q000473:pathology*; D013602:T-Lymphocytes, Cytotoxic / Q000166:cytology / Q000276:immunology*; D014162:Transfection
D018122:B7-1 Antigen; D051940:B7-2 Antigen; D019013:CD40 Antigens; D019496:Cancer Vaccines; D000949:Histocompatibility Antigens Class II; D011994:Recombinant Proteins; D007371:Interferon-gamma; D016178:Granulocyte-Macrophage Colony-Stimulating Factor