Abstract: Objective： To explore the role of γδT cells against bladder cancer and to detect the expression of stress proteins MICA/B recognized by γδT cells in bladder cancer. Methods: γδT cells from peripheral blood drawn from 6 bladder cancer patients with pamidronate stimulating were expanded. Flow cytometry was used to detect the purity and expansion folds of γδT cells, and the expression of CD107a on γδT cells after PMA/ionomycin stimulated. The cytotoxicity assay was carried out to test the cytotoxi-city of γδT cells against human bladder cancer cell lines. The expression of MICA/B on bladder cancer cell lines and in bladder cancer tissues were detected through flow cytometry and immunohistochemistry respectively. Results: γδT cells from peripheral blood drawn from 6 bladder cancer patients were successfully expanded. The purity was 75%-94% and the expansion folds were 109-371 times. After being stimulated by PMA/ionomycin, the proportion of CD107a+ γδT cells increased significantly, reaching 40%-82%. γδT cells from the 6 bladder cancer patients showed obvious cytotoxic effects on 3 human bladder cancer cell lines which was enhanced as the effector: the target ratio increased. MICA/B were detected both in 3 bladder cancer cell lines and in 26 bladder cancer tissues. The staining score of MICA/B in invasive bladder cancer was slightly higher than that in non-invasive bladder cancer, and in advanced bladder cancer was higher than that in low grade bladder cancer, but the statistical analysis showed that the staining score of MICA/B was no significant correlation between the tissue and the tumor stages and grades. Conclusion: γδT cells from the peripheral blood of the bladder cancer patients could be successfully expanded in vitro, and showed significant anti-bladder cancer effect. MICA/B were detected both in bladder cancer cell lines and in bladder cancer tissues. The statistical analysis showed that there was no significant correlation between the staining scores of MICA/B in the tissue and the tumor stages and grades.

Key words: Urinary bladder neoplasms, Receptors, antigen, T-cell, gamma-delta, MICA/B, T-lymphocytes, cytotoxic