T淋巴细胞识别自体慢性粒细胞白血病肿瘤细胞抗原的研究

Study on T lymphocyte recognition of tumor antigens on autologous CML cells

目的：验证慢性粒细胞白血病（ＣＭＬ）患者体内是否存在细胞毒Ｔ淋巴细胞前体细胞，并鉴定其表型和功能特征。方法：用混合淋巴瘤细胞培养技术，用自体瘤细胞和细胞因子刺激扩增ＣＭＬ患者骨髓和外周血单个核细胞（ＭＮＣ）。结果：ＣＭＬ缓解期和慢性期均存在对自体和异体ＣＭＬ细胞杀伤活性的Ｔ淋巴细胞，这些细胞对自体和异体正常ＭＮＣ没有杀伤活性，对正常ＣＦＵ－ＧＭ无抑制作用。而ＬＡＫ细胞对自体ＣＭＬ细胞无杀伤活性（＜１０％），只对异体ＣＭＬ细胞有杀伤活性。上述Ｔ细胞包括ＣＤ３＋ＣＤ５６＋非主要组织相容性抗原（ＭＨＣ）限制性Ｔ细胞，和ＣＤ３＋ＣＤ６－ＭＨＣ限制性Ｔ细胞。用自体ＣＭＬ细胞刺激可增加Ｔ细胞激活抗原ＣＤ２５和ＨＬＡ－ＤＲ的表达。上述Ｔ细胞对自体ＣＭＬ细胞呈较弱的增殖反应，对异体ＣＭＬ细胞几乎无增殖反应，对载有ＢＣＲ－ＡＢＬ肽的自体缓解期ＥＢ病毒转染Ｂ细胞也无增殖反应。结论：ＣＭＬ细胞可能有共同的肿瘤抗原，后者可以被Ｔ细胞识别，但尚无证据表明是ｐ２１０的融合区序列。

Objective:To investigate the existence of cytotoxic precursor cells in previously untreated or remissive chronic myelogenous leukemia(CML) patients,and identify their phenotypical and functional characteristics.Methods:Bone marrow or peripheral blood mononuclear cells from CML patients were stimulated with autologous CML cells by using mixed lymphocyte tumor cell coculture.Results:A kind of cytotoxic T lymphocytes could be generated from bone marrow or peripheral blood of CML patients.These T cells showed differential cytotoxicities against autologous and allogeneic CML cells and no activity to autologous and allogeneic normal bone marrow cells.They also exhibited no inhibitive effect on CFUGM yields.LAK cells had no effect on autologous CML cells,but showed intensive cytotoxic activity to allogeneic CML cells.The T lymphocytes obtained were CD3+ CD56+ nonMHC restricted or CD3+ CD56- MHC restricted.HLADR and CD25were expressed in a significantly larger proportion of T lymphocytes stimulated with autologous CML cells than those not stimulated.The T lymphocytes showed low proliferative response to autologous CML cell stimulation and no or least response to allogeneic CML cells,they showed also no response to EB virustransformed autologous B cells(obtained in remission) pulsed with peptides corresponding to the BCRABL joining region.Conclusion:There is probably a common tumor antigen among CMLs,this leukemiaspecific antigen can be recognized by T cells,and it shows no indication to be a p210 fusion sequence.