[Cytotoxicity of dendritic cells pulsed by CpG ODN on ovarian carcinoma cells: in vitro experiment with ovarian carcinoma cells].
OBJECTIVE
To investigate the effect of dendritic cells (DCs) pulsed by oligonucleotide containing "un-methylated cytimidine-phosphodiester bond-guanylic acid" motif (CpG ODN) on ovarian carcinoma cells.


METHODS
Dendritic cells were isolated form the peripheral monocytes and co-incubated with synthesized CpG2006, CAI125, important epithelial ovarian cancer-associated antigen, or CpG ODN + CA125 for 72 h. Flow cytometry (FC) was used to detect the expression of CD(1alpha), CD(63), CD(86), and human leucocyte antigen-DR (HLA-DR) on the cell surface. ELISA was used to detect the IL-12 level in the supernatant. T cells were obtained from the DCs. The suspensions of different groups of pulsed DCs were co-incubated with T cells. Mixed lymphocyte reaction (MLR) was used to detect the proliferating activity of the T cells. Ovarian carcinoma cells of the line OVCAR-3 were added into the culture fluid of T cells with different effector-target ratios, and then unpulsed DCs, CpG ODN-pulsed DCs, CpG ODN + CA125-pulsed DCs, and CA125-pulsed DCs were added respectively. MTT colorimetry was performed to measure the A values of different wells so as to calculate the killing rate.


RESULTS
(1) The expression levels of CD(63), CD(86), and HLA-DR on the membranes of the CpG ODN-pulsed DCs and CpG ODN + C125-pulsed DCs were significantly higher than those of the un-pulsed DCs (all P < 0.01), however, there were no significant differences in the expression of CD(1alpha) among different groups (all P > 0.05). (2) The IL-12 levels in the supernatants of the CpG ODN-pulsed DCs and CpG ODN + C125-pulsed DCs were significantly higher than those of the unpulsed and CA125-pulsed groups (all P < 0.01). (3) MLR showed that the T cell proliferation rates of the T cells sensitized by the CpG ODN-pulsed DCs and CpG ODN + C125-pulsed DCs were both higher than those of the T cells stimulated by the unpulsed and CA125-pulsed groups when the effector: target ratio was 10:1 (all P < 0.01). (4) The killing rates on OVCAR-3 cells of the CTLs sensitized by CpG ODN + CA125-pulsed DCs at the same effector: target ratios were all higher than those of the CTLs sensitized by the CpG ODN-pulsed DCs, CA125-pulsed DCs, and unpulsed DCs (all P < 0.01), the killing activity of the cytotoxic T lymphocytes (CTLs) sensitized by CpG ODN+CA125-pulsed DCs on the OVCAR-3 cells was shown even when the effector: target ratio was as low as 10:1, and then increased along with the increase of the effector: target ratio to the height of 64.9%.


CONCLUSIONS
Capable of inducing immune cytotoxicity on ovarian carcinoma, DCs sensitized by CpG ODN + CA125 may have a great implication on clinical application.
Ye
Ming-Zhu
MZ
Department of Obstetrics and Gynecology, Second Hospital of Jilin University, Changchun 130041, China.
Li
He-Lian
HL
Han
Li-Ying
LY
D015703:Antigens, CD / Q000276:immunology; D018949:Antigens, CD1 / Q000276:immunology; D051940:B7-2 Antigen / Q000276:immunology; D018394:CA-125 Antigen / Q000276:immunology / Q000494:pharmacology; D045744:Cell Line, Tumor; D018920:Coculture Techniques; D003602:Cytotoxicity, Immunologic / Q000276:immunology*; D003713:Dendritic Cells / Q000166:cytology / Q000187:drug effects* / Q000276:immunology; D005434:Flow Cytometry; D006801:Humans; D007959:Lymphocyte Culture Test, Mixed; D009838:Oligodeoxyribonucleotides / Q000276:immunology / Q000494:pharmacology*; D010980:Platelet Membrane Glycoproteins / Q000276:immunology; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology; D060149:Tetraspanin 30
D015703:Antigens, CD; D018949:Antigens, CD1; D051940:B7-2 Antigen; D018394:CA-125 Antigen; C554586:CD63 protein, human; D009838:Oligodeoxyribonucleotides; D010980:Platelet Membrane Glycoproteins; D060149:Tetraspanin 30; C489630:1018 oligonucleotide