bcr3-abl2多肽诱导脐血T细胞受体Vβ亚家族T细胞克隆性增殖的研究

Clonal expansion of TCR Vβ subfamily T cells induced by bcr3-abl2 peptide

目的 了解bcr3 abl2多肽诱导T细胞受体 (TCR)Vβ亚家族T细胞克隆性增殖情况。 方法 以人工合成bcr3 abl2多肽联合IL 2 +抗CD3单克隆抗体 (单抗 )诱导脐血T细胞增殖 ,运用RT PCR 基因扫描技术分析其TCRVβ亚家族的利用和克隆性特点。结果 bcr3 abl2多肽成功诱导 3份脐血单个核细胞 (MNC)产生多肽特异T细胞。bcr3 abl2多肽和CD3单抗 +IL 2均可诱导脐血T细胞扩增 ,多肽诱导的新增Vβ亚家族表达与不加多肽的CD3单抗 +IL 2诱导组的T细胞不完全相同。培养前和单用CD3单抗 +IL 2诱导后的T细胞绝大多数为多克隆性 ,而bcr3 abl2多肽诱导 1周或 2周后 ,分别在 3例脐血中诱导出寡克隆增殖和呈寡克隆增殖趋势T细胞。结论 bcr3 abl2多肽可在体外诱导出抗慢性粒细胞白血病细胞的脐血特异性细胞毒性T淋巴细胞 (CTL) ,该CTL作用可能是由优势表达的Vβ亚家族克隆性T细胞所介导。

Objective To investigate the clonal expansion of T cell receptor(TCR) Vβ subfamily T cells from cord blood induced by bcr3-abl2 peptide in vitro. Methods T cells from 3 units of cord blood were amplified by anti-CD 3 monoclonal antibody (McAb) and IL-2 with or without synthetic b3a2 peptide. T cell specific cytotoxicity was analyzed by lactate dehydrogenase(LDH) assay, TCR Vβ subfamilies by using reverse transcriptase-polymerase chain reaction (RT-PCR) and genescan technique. Results bcr3-abl2 peptide specific cytotoxicity T cells were successfully induced from the 3 units of cord blood by synthetic b3a2 peptide. Compared with that in CD 3 McAb induced cells, distribution pattern of TCR Vβ repertoire was different in T cells induced with b3a2 peptide. Oligoclonal and oligoclonal tendency TCR Vβ subfamily T cells could be identified in cord blood T cells induced by b3a2 peptide in 1 or 2 weeks, whereas those induced by anti-CD 3 McAb and IL-2 were mostly polyclonal. Conclusion The cytotoxicity T cells with anti-CML specificity could be induced by b3a2 peptide. The specific anti-CML cytotoxicity may be derived from the clonal expansion TCR Vβ subfamily T cells.