单倍型及同胞相合异基因造血干细胞移植后巨细胞病毒特异性细胞毒性T细胞重建规律的比较研究

Cytomegalovirus (CMV) disease is a major complicaiton after allogeneic hematological stem cell transplantation (allo-HSCT) and also an improtant disease that results in transplant-related mortality after allo-HSCT. Several articals have already confirmed that CMT-specific cytotoxic T cells have been the key to influence the prognosis of patients with CMV infection after transplantation. We found that there were some differences in the incidence and severity of CMV infection between the patients receiving haploidentical HSCT and patients receiving HLA-matched sibling HSCT. These phenomenon probably suggested that there were some differences in the reconstruction of CMV-specific CTL between patients receiving haploidentical HSCT and patients receiving HLA-matched sibling HSCT. This study was performed to investigate the numbers and funtions of CMV- specific CTL by using HLA-CMV peptide pentamer, lymphocyte proliferation assays, intracellular cytokine stating and cytotoxicity funtion. Furthermore, this study was performed to compare the difference of reconstruction of CMV-specific CTL between patients receiving haploidentical HSCT and patients receiving HLA-matched sibling HSCT, as well as, to explore the relation between reconstruction of CMV-specific CTL and the development of CMV disease. The clarification of these problems is not only helpful to explain the reason that there are some differences in the incidence and severity of CMV infection between patients receiving haploidentical HSCT and patients receiving HLA-matched sibling HSCT, and more important is helpful to find some markers in order to stratify the patients, and finally improve the long-term survival of transplant patients.

巨细胞病毒（CMV）病是异基因造血干细胞移植后严重的合并症，亦是导致移植相关死亡的重要疾病之一。文献已证实CMV-特异性细胞毒性T细胞（CTL）是影响移植后CMV感染转归的关键。我们发现单倍型和同胞相合移植后CMV感染和CMV病的发病规律明显不同，因此推测两种移植体系下CMV特异性CTL的重建规律不同。本研究拟应用HLA-CMV肽五聚体、细胞内细胞因子测定、淋巴细胞增殖实验和细胞杀伤功能评估移植后CMV-特异性CTL的数量、亚群及功能的重建，前瞻性比较单倍型和同胞相合移植后CMV-特异性CTL重建规律的异同；并探讨CMV-特异性CTL重建与移植后CMV病的相关性。此问题的阐明，不仅有助于解释两种移植体系下CMV感染发病规律不同的原因，更重要的是有助于发现用于预警及降低CMV病的生物指标及方法，进而改善移植患者的长期生存。

本研究摘要首先，我们通过回顾性分析488例移植后发生CMV感染的病例阐明了allo-HSCT后难治性CMV感染的流行病学特点、高危因素及其与CMV病的关系，和对移植后生存的影响。随后，我们结合前瞻性临床队列，采用HLA-I类五聚肽检测CMV特异性T细胞的重建规律，阐明其难治性CMV感染的关系。研究数据.难治性CMV感染组CMV病的发生率和移植相关死亡率高于非难治性CMV感染组（分别是11.9% vs. 0.8% 和17.1% vs. 8.3%）。多因素分析显示allo-HSCT后+100天内的难治性CMV感染是CMV病（HR=10.539, 95% CI 2.467-45.015, p=0.001）的独立危险因素，allo-HSCT后+60天后发生难治性CMV感染是影响移植相关死亡（transplan-related mortality, TRM）的独立危险因素（HR=8.435, 95% CI 1.511-47.099, p=0.015）。影响难治性CMV感染发生的高危因素有单倍体移植（HR=2.02, 95% CI 1.597-2.536, p<0.001）和急性移植物抗宿主病（HR=1.717, 95% CI 1.102-2.675, p=0.017）。+30天CMV特异性CD8+ TCM淋巴细胞亚群水平低（<0.04/µL）的患者组难治性CMV感染发生率明显高于+30天CMV特异性CD8+TCM淋巴细胞亚群水平高的患者组（≥0.04/µL）（75.86% vs. 7.14%，p=0.001），前者在allo-HSCT后半年内的CMV特异性CD8+T淋巴细胞和CMV特异性CD8+TCM亚群重建均明显差于后者（p=0.037）。多因素分析显示+30天CMV特异性CD8+TCM淋巴细胞亚群水平是影响难治性CMV感染发生的独立危险因素（HR=0.042, 95% CI 0.005-0.329, p=0.003）。课题核心结果和关联结果发表SCI文章16篇，核心期刊文章6篇，培养博士生3名。