Kollgaard T, Petersen S L, Hadrup S Reker, Masmas T N, Seremet T, Andersen M H, Madsen H O, Vindeløv L, thor Straten P
Tumor Immunology Group, Institute of Cancer Biology, Danish Cancer Society, Copenhagen, Denmark.
Leukemia. 2005 Dec;19(12):2273-80. doi: 10.1038/sj.leu.2403972.
We have analyzed the clonotype composition of CD8+ T cells following nonmyeloablative (NMA) conditioning and hematopoietic cell transplantation (HCT), of patients with chronic lymphocytic leukemia (CLL). Consecutive analyses of blood samples taken up to 2 years following HCT, demonstrated that CD8+ T-cell clonality was highly dynamic in the early phases after HCT, but became more stable after 4-5 months. Moreover, donor lymphocyte infusion (DLI) given for disease progression in one of the patients led to establishment of recurrent as well as new T-cell clonotypes. This coincided with disease remission, strongly suggesting that these T cells were engaged with anti-CLL cytotoxicity. To examine the functional capacity of stable clonally expanded T cells after HCT, CD8+ T cells isolated post-transplant from the recipients were stimulated ex vivo with CLL cells and subsequently analyzed by FACS for surface expression of the marker for cytotoxic activity, CD107a. Stimulation with CLL cells indeed led to surface expression of CD107a, and clonotype analyses of sorted cells demonstrated that CD107a positive T cells were stably expanded following HCT. Our data suggest that clonally expanded CD8+ T-cell clones participate in the ongoing T-cell response against CLL cells following HCT with NMA conditioning.
我们分析了慢性淋巴细胞白血病（CLL）患者在非清髓性（NMA）预处理和造血细胞移植（HCT）后CD8⁺T细胞的克隆型组成。对HCT后长达2年采集的血样进行连续分析表明，HCT后的早期阶段CD8⁺T细胞克隆性高度动态变化，但在4 - 5个月后变得更加稳定。此外，其中一名患者因疾病进展接受供体淋巴细胞输注（DLI）后，导致复发以及新的T细胞克隆型的建立。这与疾病缓解同时发生，强烈表明这些T细胞参与了抗CLL细胞毒性作用。为了检测HCT后稳定克隆扩增的T细胞的功能能力，从受者移植后分离的CD8⁺T细胞在体外与CLL细胞一起刺激，随后通过荧光激活细胞分选术（FACS）分析细胞毒性活性标志物CD107a的表面表达。用CLL细胞刺激确实导致了CD107a的表面表达，并且对分选细胞的克隆型分析表明，HCT后CD107a阳性T细胞稳定扩增。我们的数据表明，在NMA预处理的HCT后，克隆扩增的CD8⁺T细胞克隆参与了针对CLL细胞的持续T细胞应答。
