A Preliminary Study On Specific Cytotoxicity In Vitro Induced By Dendrtic Cells Pulsed With Tumor Antigens Towards Bladder Cancer Cells

[Objective] To study specific cytotoxicity induced by dendrtic cells pulsed with different tumor antigen-extracts towards bladder cancer cell lines and to investigate feasibility of the therapy on tumor vaccines based on dendrtic cells directed bladder cancer . [Methods] Health Human PBMCs cultured with RPMI1640+10%FBS contained rh GM-CSF(800u/ml)+rh IL-4(1, OOOu/ml)+rhTNF- (lOng/ml) in vitro for 9 days, and DCs were harvested. After 1X 107 BIU-87 cells (human bladder transitional cell carcinoma cell line) were eluted by citric acid-phosptat buffer or frozen and molten repeatedly for 4 times, tumor antigens were obtained, then detected protein content . Next DCs pulsed with tumor antigens can be activated .then T lymphocytes incubated activated DCs can induce tumor specific CTLs. Specific cytotoxicity caused by the different CTLs towards bladder cancer cells can be detected through lactate dehydrogenase release technique. Also DCs can excrete IL-12 p70, which were able to be detected by ELISA technique. [Results]1.The tumor antigen content obtained by citric acid-phosptat buffer was (426. 0 4. 3) g, and that by frozen and molten repeatedly was (681. 0 5. 6) g. 2. Through lactate dehydrogenase release technique , CTLs activated by different DCs can kill BIU -87 cells significantly while cytotoxicity induced by dendrtic cells pulsed with tumor antigens obtained by citric acid- phosptat buffer was stronger, which had a statistic significance(p<0.05). 3. The DCS excreting capabicity of IL-12 p70 were different in different stages through ELISA technique: the longer the culture, the stronger the excreting capabicity . In addition, differentextracted methods can affect the value of excretion, that is, the capabicity coming from citric acid- phosptat buffer was stronger than that coming from frozen and molten repeatedly which had a statistic significance(p<0.05).[Conclusions] DCs are the most powerful professional antigen presenting cells Health Human PBMCs cultured with cytokines rh GM-CSF+rh IL-4+rhTNF- a in vitro can produce matured DCs. BIU-87 cells Were eluted by citric acid- phosptat buffer or frozen and molten repeatedly , then tumor antigens were obtained. DCs loaded bladder tumor antigens can produce remarkably specific CTLs . DCs pulsed with bladder tumor antigens can excret more IL-12 .which play a important role in stimulation of DCs towards the CTLS . The CTLs can kill tumor cells specifically, which indicates that anti-tumor biological therapy that circles DCs is expected to improve the overall therapeutic level of bladder tumor.