PURPOSE: Cancer stem cells have recently been thought to be closely related to tumor development and reoccurrence. It may be a promising way to cure malignant glioma by using glioma stem cell-targeted dendritic cells as a tumor vaccine. In this study, we explored whether pulsing dendritic cells with antigens of glioma stem cells was a potent way to induce specific cytotoxic T lymphocytes and anti-tumor immunity. MATERIALS AND METHODS: Cancer stem cells were cultured from glioma cell line U251. Lysate of glioma stem cells was obtained by the repeated freezing and thawing method. Dendritic cells (DCs) were induced and cultured from the murine bone marrow cells, the biological characteristics were detected by electron microscope and flow cytometry. The DC vaccine was obtained by mixing DCs with lysate of glioma stem cells. The DC vaccine was charactirizated through the mixed lymphocyte responses and cell killing experiment in vitro. Level of interferon-gamma (IFN-gamma) in the supernatant was checked by ELISA. RESULTS: After stimulation of lysate of glioma stem cell, expression of surface molecules of DC was up-regulated, including CD80, CD86, CD11C and MHC-II. DCs pulsed with lysate of glioma stem cells were more effective than the control group in stimulating original glioma cells-specific cytotoxic T lymphocytes responses, killing glioma cells and boosting the secretion of IFN-gamma in vitro. CONCLUSION: The results demonstrated DCs loaded with antigens derived from glioma stem cells can effectively stimulate naive T cells to form specific cytotoxic T cells, kill glioma cells cultured in vitro.
Animals ; Antigens, Neoplasm/immunology ; Apoptosis ; Brain Neoplasms/*therapy ; Cancer Vaccines/*therapeutic use ; Cell Line, Tumor ; Cell Proliferation ; Dendritic Cells/*cytology ; Enzyme-Linked Immunosorbent Assay ; Flow Cytometry ; Glioma/*therapy ; Humans ; Interferon-gamma/metabolism ; Male ; Mice ; Mice, Inbred C57BL ; Neoplasm Transplantation ; Neoplastic Stem Cells/*cytology ; T-Lymphocytes, Cytotoxic/immunology

OBJECTIVETo assess the local immune response in patients with hepatocellular carcinoma after percutaneous microwave coagulation therapy (PMCT).

METHODSSeventy-eight patients with hepatocellular carcinoma underwent PMCT. Both cancerous and adjacent liver tissue were taken before, and 3, 17 and 30 days after PMCT using ultrasound-guided liver biopsy. Specimens were stained by immunohistochemical techniques for detecting CD3, CD45RO, CD56, CD68, and CD20 positive cells.

RESULTSA few CD3, CD45RO, CD56, CD68 and CD20 positive cells were observed in the cancer stroma and surrounding sinusoids in liver tissue pre-PMCT. The number of immunocytes, except for CD20 positive cells, was significantly increased both within the cancer and the adjacent liver tissue, with a larger increase in tumor tissue at day 3 post-PMCT compared with pre-PMCT. These immunocytes were enlarged in size. The number of CD3, CD45RO and CD56 positive cells peaked at day 17 and CD68 positive cells peaked at days 3 post-PMCT. At day 30 post-PMCT, this increase still existed. These infiltrating immunocytes distributed in the parenchyma of the tumor, and within the lumen of small blood vessels after PMCT. In addition, more infiltrated immune cells were seen in cancer cell spaces.

CONCLUSIONSA change in immunocyte infiltration takes place in number, configuration and location after patients with HCC are treated with percutaneous microwave coagulation, suggesting that local immune function is enhanced post-PMCT.

Adult ; Aged ; Aged, 80 and over ; Antigens, CD ; analysis ; Carcinoma, Hepatocellular ; immunology ; pathology ; therapy ; Electrocoagulation ; Female ; Humans ; Immunohistochemistry ; Liver Neoplasms ; immunology ; pathology ; therapy ; Male ; Microwaves ; therapeutic use ; Middle Aged ; T-Lymphocytes ; immunology