Abstract：
BACKGROUND: Uremia-associated immunodeficiency, mainly characterized by T cell dysfunction, exists in patients on maintenance hemodialysis (MHD) and promotes systemic inflammation. However, T cell senescence, one of the causes of T cell dysfunction, has not been clearly revealed yet. In this cross-sectional research, we aimed to study the manifestation of T cell premature senescence in MHD patients and further investigate the associated clinical factors.
METHODS: 76 MHD patients including 33 patients with cardiovascular diseases (CVD) and 28 patients with arteriovenous fistula (AVF) event history were enrolled in this study. Complementarity determining region 3 (CDR3) of T cell receptor (TCR) was analyzed by immune repertoire sequencing (IR-Seq). CD28- T cell subsets and expression of senescence marker p16 and p21 genes were detected by multicolor flow cytometry and RT-qPCR, respectively.
RESULTS: MHD patients had significantly decreased TCR diversity (P < 0.001), increased CDR3 clone proliferation (P = 0.001) and a left-skewed CDR3 length distribution. The proportion of CD4 + CD28- T cells increased in MHD patients (P = 0.014) and showed a negative correlation with TCR diversity (P = 0.001). p16 but not p21 expression in T cells was up-regulated in MHD patients (P = 0.039). Patients with CVD exhibited increased expression of p16 and p21 genes (P = 0.010 and 0.004, respectively), and patients with AVF events showed further TCR diversity and evenness reduction (P = 0.002 and 0.017, respectively) compared to patients without the comorbidities. Moreover, age, average convection volume, total cholesterol, high-density lipoprotein cholesterol and transferrin saturation were associated with TCR diversity or CD4 + CD28- T cell proportion (P < 0.05).
CONCLUSIONS: MHD patients undergo T cell premature senescence characterized by significant TCR diversity reduction and repertoire skew, as well as accumulation of the CD4 + CD28- subset and up-regulation of p16 gene. Patients with CVD or AVF events show higher level of immunosenescence. Furthermore, T cell senescence in MHD patients is associated with blood cholesterol and uremic toxin retention, suggesting potential intervention strategies in the future.
METHODS: 76 MHD patients including 33 patients with cardiovascular diseases (CVD) and 28 patients with arteriovenous fistula (AVF) event history were enrolled in this study. Complementarity determining region 3 (CDR3) of T cell receptor (TCR) was analyzed by immune repertoire sequencing (IR-Seq). CD28- T cell subsets and expression of senescence marker p16 and p21 genes were detected by multicolor flow cytometry and RT-qPCR, respectively.
RESULTS: MHD patients had significantly decreased TCR diversity (P < 0.001), increased CDR3 clone proliferation (P = 0.001) and a left-skewed CDR3 length distribution. The proportion of CD4 + CD28- T cells increased in MHD patients (P = 0.014) and showed a negative correlation with TCR diversity (P = 0.001). p16 but not p21 expression in T cells was up-regulated in MHD patients (P = 0.039). Patients with CVD exhibited increased expression of p16 and p21 genes (P = 0.010 and 0.004, respectively), and patients with AVF events showed further TCR diversity and evenness reduction (P = 0.002 and 0.017, respectively) compared to patients without the comorbidities. Moreover, age, average convection volume, total cholesterol, high-density lipoprotein cholesterol and transferrin saturation were associated with TCR diversity or CD4 + CD28- T cell proportion (P < 0.05).
CONCLUSIONS: MHD patients undergo T cell premature senescence characterized by significant TCR diversity reduction and repertoire skew, as well as accumulation of the CD4 + CD28- subset and up-regulation of p16 gene. Patients with CVD or AVF events show higher level of immunosenescence. Furthermore, T cell senescence in MHD patients is associated with blood cholesterol and uremic toxin retention, suggesting potential intervention strategies in the future.
摘要：
背景：尿毒症相关免疫缺陷，主要表现为T细胞功能障碍,存在于维持性血液透析（MHD）患者中，并促进全身性炎症。然而,T细胞衰老,T细胞功能障碍的原因之一，还没有明确透露。在这项横断面研究中，我们旨在研究MHD患者T细胞早衰的表现，并进一步探讨其相关临床因素。
方法：本研究纳入76例MHD患者，包括33例心血管疾病（CVD）患者和28例有动静脉瘘（AVF）事件史的患者。通过免疫组库测序(IR-Seq)分析T细胞受体(TCR)的互补决定区3(CDR3)。应用多色流式细胞术和RT-qPCR检测CD28-T细胞亚群和衰老标志物p16和p21基因的表达,分别。
结果：MHD患者的TCR多样性明显降低（P<0.001），增加CDR3克隆增殖（P=0.001）和左偏CDR3长度分布。MHD患者CD4+CD28-T细胞比例升高(P=0.014),与TCR多样性呈负相关(P=0.001)。在MHD患者中，T细胞中p16而不是p21表达上调（P=0.039）。心血管疾病患者p16和p21基因表达增加（P分别为0.010和0.004）。与没有合并症的患者相比,有AVF事件的患者显示出进一步的TCR多样性和均匀度降低(分别为P=0.002和0.017).此外，年龄,平均对流体积,总胆固醇,高密度脂蛋白胆固醇和转铁蛋白饱和度与TCR多样性或CD4+CD28-T细胞比例相关(P<0.05)。
结论：MHD患者经历T细胞早衰，其特征是TCR多样性显著降低和谱系偏斜，以及CD4+CD28-亚群的积累和p16基因的上调。有CVD或AVF事件的患者表现出更高水平的免疫衰老。此外，MHD患者的T细胞衰老与血胆固醇和尿毒症毒素滞留有关，提出未来潜在的干预策略。
方法：本研究纳入76例MHD患者，包括33例心血管疾病（CVD）患者和28例有动静脉瘘（AVF）事件史的患者。通过免疫组库测序(IR-Seq)分析T细胞受体(TCR)的互补决定区3(CDR3)。应用多色流式细胞术和RT-qPCR检测CD28-T细胞亚群和衰老标志物p16和p21基因的表达,分别。
结果：MHD患者的TCR多样性明显降低（P<0.001），增加CDR3克隆增殖（P=0.001）和左偏CDR3长度分布。MHD患者CD4+CD28-T细胞比例升高(P=0.014),与TCR多样性呈负相关(P=0.001)。在MHD患者中，T细胞中p16而不是p21表达上调（P=0.039）。心血管疾病患者p16和p21基因表达增加（P分别为0.010和0.004）。与没有合并症的患者相比,有AVF事件的患者显示出进一步的TCR多样性和均匀度降低(分别为P=0.002和0.017).此外，年龄,平均对流体积,总胆固醇,高密度脂蛋白胆固醇和转铁蛋白饱和度与TCR多样性或CD4+CD28-T细胞比例相关(P<0.05)。
结论：MHD患者经历T细胞早衰，其特征是TCR多样性显著降低和谱系偏斜，以及CD4+CD28-亚群的积累和p16基因的上调。有CVD或AVF事件的患者表现出更高水平的免疫衰老。此外，MHD患者的T细胞衰老与血胆固醇和尿毒症毒素滞留有关，提出未来潜在的干预策略。
