[Experimental studies on the characteristics of suicide gene system HSV-tk/GCV and its effect on dendritic cells].
OBJECTIVE
To study the characteristics of suicide gene system of the herpes simplex virus thymidine kinase (HSV-tk) gene in tumor cells and explore the apoptosis phenomena in this system and its effect on dendritic cells (DC).


METHODS
HSV-tk was transduced into the breast cancer cell line MCF-7 cells with a retrovirus vector. Apoptosis was examined by electro-microscopy and FACS. DCs were induced from cord blood CD(34)(+) cells with a combination of cytokines (GM-CSF, TNF-alpha, SCF and FL) and (3)H-TdR was adopted to determine the proliferation of T cells.


RESULTS
In vitro experiment showed a dose-dependent cell killing of the HSV-tk gene transducted cells on ganciclovir (GCV) treatment. The apoptosis rate increased to 31.3% from the control group of 19.3%. Apoptosis is the important mechanism in bystander effect of HSV-tk/GCV system. The CD(1a)(+) and HLA-DR(+) cells in the induced DC were of (27.18 +/-1.56)% and (93.7 +/- 1.0)%, respectively. Co-incubation of DC with apoptotic cells further stimulated the proliferation of T cells.


CONCLUSIONS
It suggested that HSV-tk/GCV system, alone or combined with radiotherapy, be a promising suicide gene therapy for cancer patient and an approach to enhancing DC function.
Wang
X
X
Beijing Institute of Transfusion Medicine, Beijing 100850, China.
Li
L
L
Feng
K
K
Bai
L
L
Pei
X
X
D016475:3T3 Cells; D000818:Animals; D018952:Antigens, CD34 / Q000032:analysis; D000998:Antiviral Agents / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects / Q000235:genetics; D024201:Bystander Effect; D002455:Cell Division / Q000276:immunology; D002460:Cell Line; D018920:Coculture Techniques; D003713:Dendritic Cells / Q000166:cytology / Q000276:immunology*; D005312:Fetal Blood / Q000166:cytology / Q000187:drug effects / Q000276:immunology; D015774:Ganciclovir / Q000494:pharmacology*; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology; D006801:Humans; D051379:Mice; D018139:Simplexvirus / Q000201:enzymology*; D019089:Stem Cell Factor / Q000494:pharmacology; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology; D013937:Thymidine Kinase / Q000235:genetics*; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D018952:Antigens, CD34; D000998:Antiviral Agents; D019089:Stem Cell Factor; D014409:Tumor Necrosis Factor-alpha; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D013937:Thymidine Kinase; D015774:Ganciclovir