Research on PR1 specific cytotoxic T lymphocytes of HLA-A0201 positive chronic myelogenous leukemia / 白血病·淋巴瘤

ABSTRACT

Objective To evaluate the relationship between proportion of PR1 specific cytotoxic T lymphocytes (CTLs) in the peripheral blood and prognosis and curative effect in patients with HLA-A0201 positive chronic myelogenous leukemia (CML),and to discuss whether PR1 peptide could be used as the following immune therapeutic method for patients who had achieved the standard of stop treatment.Methods The soluble HLA-A0201/PR1 tetramer and flow cytometry were applied to determine the proportion and the frequency of PR1 specific CTLs in peripheral blood from 28 HLA-A0201 positive CML patients.The proportions were compared among different phases of patients.The correlations between the proportion of PR1 specific CTLs and clinical parameters were analyzed.Results There was a negative correlation between PR1 specific CTLs and PCR (bcr-abl/abl)Is (r =-0.658,P ＜ 0.001).The frequencies of PR1 specific CTLs at 3-month,6-month,9-month,12-month,2-year,3-year,4-year,5-year,6-year were (0.06±0.02) ％,(0.10± 0.02) ％,(0.14±0.02) ％,(0.16±0.02) ％,(0.20±0.03) ％,(0.18±0.03) ％,(0.18±0.01) ％,(0.17±0.05) ％ and (0.18±0.03) ％,respectively.The frequency of PR1 specific CTLs at 3-month,6-month or 9-month was statistically different compared with that of the other time spots (P ＜ 0.05),and there were no statistical differencies among the frequencies at 1-year,2-year,3-year,4-year,5-year,6-year (P ＞ 0.05).For patients treated with IM 400 mg qd,the frequency of PR1 specific CTLs in high-risk group was lower than that in low-risk or intermediate-risk groups.Conclusion PR1 specific CTLs can be detected in patients who achieved good curative effect,and is correlated with tumor burden,which indicates that PR1 specific CTLs may be related to the action of resisting leukemia and provide the evidence for PR1 peptide as a potential immune therapeutic schedule in patients who have achieved stable MR45 and MR50.