Rezvani Katayoun, Grube Matthias, Brenchley Jason M, Sconocchia Giuseppe, Fujiwara Hiroshi, Price David A, Gostick Emma, Yamada Ko, Melenhorst Jan, Childs Richard, Hensel Nancy, Douek Daniel C, Barrett A John
National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA.
Blood. 2003 Oct 15;102(8):2892-900. doi: 10.1182/blood-2003-01-0150. Epub 2003 Jun 26.
Antigens implicated in the graft-versus-leukemia (GVL) effect in chronic myeloid leukemia (CML) include WT1, PR1, and BCR-ABL. To detect very low frequencies of these antigen-specific CD8+ T cells, we used quantitative polymerase chain reaction (qPCR) to measure interferon-gamma (IFN-gamma) mRNA production by peptide-pulsed CD8+ T cells from HLA-A*0201+ healthy volunteers and from patients with CML before and after allogeneic stem cell transplantation (SCT). Parallel assays using cytomegalovirus (CMV) pp65 tetramers demonstrated the IFN-gamma copy number to be linearly related to the frequency of tetramer-binding T cells, sensitive to frequencies of 1 responding CD8+ T cell/100 000 CD8+ T cells. Responses to WT1 and PR1 but not BCR-ABL were detected in 10 of 18 healthy donors. Responses to WT1, PR1, or BCR-ABL were observed in 9 of 14 patients with CML before SCT and 5 of 6 after SCT, often to multiple epitopes. Responses were higher in patients with CML compared with healthy donors and highest after SCT. These antigen-specific CD8+ T cells comprised central memory (CD45RO+CD27+CD57-) and effector memory (CD45RO-CD27-CD57+) T cells. In conclusion, leukemia-reactive CD8+ T cells derive from memory T cells and occur at low frequencies in healthy individuals and at higher frequencies in patients with CML. The increased response in patients after SCT suggests a quantitative explanation for the greater effect of allogeneic SCT.
慢性髓性白血病（CML）中与移植物抗白血病（GVL）效应相关的抗原包括WT1、PR1和BCR-ABL。为了检测这些抗原特异性CD8⁺ T细胞的极低频率，我们使用定量聚合酶链反应（qPCR）来测量来自HLA-A*0201⁺健康志愿者以及异基因干细胞移植（SCT）前后的CML患者的肽脉冲CD8⁺ T细胞产生的干扰素-γ（IFN-γ）mRNA。使用巨细胞病毒（CMV）pp65四聚体的平行检测表明，IFN-γ拷贝数与四聚体结合T细胞的频率呈线性相关，对1个反应性CD8⁺ T细胞/100 000个CD8⁺ T细胞的频率敏感。在18名健康供者中的10名中检测到对WT1和PR1而非BCR-ABL的反应。在14名SCT前的CML患者中有9名以及SCT后的6名患者中有5名观察到对WT1、PR1或BCR-ABL的反应，通常针对多个表位。CML患者的反应高于健康供者，且在SCT后最高。这些抗原特异性CD8⁺ T细胞包括中枢记忆（CD45RO⁺CD27⁺CD57⁻）和效应记忆（CD45RO⁻CD27⁻CD57⁺）T细胞。总之，白血病反应性CD8⁺ T细胞源自记忆T细胞，在健康个体中频率较低，在CML患者中频率较高。SCT后患者反应的增加为异基因SCT的更大效应提供了定量解释。
