Selective expansion of donor‐derived regulatory T cells after allogeneic bone marrow transplantation in a patient with IPEX syndrome

IPEX syndrome is a rare and fatal disorder caused by absence of regulatory T cells (Tregs) due to congenital mutations in the Forkhead box protein 3 gene. Here, we report a patient with IPEX syndrome treated with RIC followed by allogeneic BMT from an HLA‐matched sibling donor. We could achieve engraftment and regimen‐related toxicity was well tolerated. Although the patient was in mixed chimera and the ratio of donor cells in whole peripheral blood remained relatively low, selective and sustained expansion of Tregs determined as CD4+CD25+Foxp3+ cells was observed. Improvement in clinical symptoms was correlated with expansion of donor‐derived Tregs and disappearance of anti‐villin autoantibody, which was involved in the pathogenesis of gastrointestinal symptoms in IPEX syndrome. This clinical observation suggests that donor‐derived Tregs have selective growth advantage in patients with IPEX syndrome even in mixed chimera after allogeneic BMT and contribute to the control of clinical symptoms caused by the defect of Tregs.     

Residual C‐peptide in type 1 diabetes: what do we really know?

Connecting peptide, or C‐peptide, is a protein that joins insulin's α and B chains in the proinsulin molecule. During insulin synthesis, C‐peptide is cleaved from proinsulin and secreted in an equimolar concentration to insulin from the β cells. Because C‐peptide experiences little first‐pass clearance by the liver, and because levels are not affected by exogenous insulin administration, it may be used as a marker of endogenous insulin production and a reflection of β‐cell function. Residual β‐cell function, as measured by C‐peptide in those with type 1 diabetes (T1D), has repeatedly been demonstrated to be clinically important. The Eisenbarth model of type 1 diabetes postulated immune‐mediated linear loss of β cells, with clinical diagnosis occurring when there was insufficient insulin secretion to meet glycemic demand. Moreover, the model also implied that all individuals with T1D rapidly and inevitably progressed to absolute insulin deficiency. Correspondingly, it was assumed that most people with longstanding T1D would show little to no residual C‐peptide secretion. While more than a quarter century of data confirms that this model remains largely true and appropriately serves as the basis for prevention studies, accumulating evidence suggests that the natural history of β‐cell function before, during and after diagnosis is more complex. In this review, we discuss the clinical benefits of residual insulin secretion and present recent data about the natural history of insulin secretion in those with, or at risk for T1D.     

儿童急性白血病血清25羟维生素D3的水平及其临床意义

目的：通过检测儿童急性白血病（AL）血清25羟维生素D3的水平,并探讨其临床意义。方法用双抗体夹心酶联免疫吸附试验（ELISA）方法分别测定60例急性白血病患儿,其中30例急性淋巴细胞白血病（ALL）患儿和30例急性髓细胞白血病（AML）患儿在初诊未治前、缓解1个月后、缓解6个月后和对照组30例健康儿童血清25羟维生素D3的水平,并且对其进行比较。结果血清25羟维生素D3的水平：AL初诊未治组（30.95±6.32）nmol／L,AL缓解1个月组（51.32±14.62） nmol／L,AL缓解6个月组（40.13±9.92）nmol／L;ALL初诊未治组（30.51±13.81）nmol／L,ALL缓解1个月组（61.11±18.93）nmol／L,ALL缓解6个月组（44.43±12.60）nmol／L;AML初诊未治组（31.44±7.13）nmol／L,AML缓解1个月组（41.24±10.29）nmol／L,AML缓解6个月组（36.73±9.73）nmol／L;正常对照组（58.71±8.97）nmol／L。方差分析结果：AL、ALL和AML初诊未治疗组的血清25羟维生素D3的水平均明显低于正常对照组（P＜0.05）。AL （初诊未治组、缓解1个月组、缓解6月组）和ALL（初诊未治组、缓解1个月组、缓解6个月组）各组间血清25羟维生素D3的水平差异有显著性（P＜0.05）,AL缓解1个月组和ALL缓解1个月组血清25羟维生素D3的水平与正常对照组差异无显著性;AL和ALL缓解6个月组血清25羟维生素D3的水平低于正常对照组（P＜0.05）。AML三组的血清25羟维生素D3的水平均低于正常对照组（P＜0.05）;ALL与AML初诊未治组血清25羟维生素D3的水平无显著性差异;AL、ALL和AML在化疗过程中血清25羟维生素D3的水平都是先上升,之后又有所下降或者停止上升的趋势。结论动态监测血清25羟维生素D3的水平在儿童急性白血病不同的治疗阶段的变化能够作为判断病情的发展以及评估治疗后效果的一项指标。     

犬急性心肌缺血后左室功能变化与心肌细胞凋亡

目的观察犬急性心肌缺血后左心室壁动度、射血功能、细胞凋亡与心肌组织中caspase3活性的变化。方法犬30只随机分为实验组15只及对照组15只,实验组结扎左冠状动脉前降支近端,结扎时间分别为10min、30min、60min,每一时间点5只,对照组游离左冠状动脉前降支近端,不结扎。心肌组织行三苯四氮唑(TTC)染色,梗死区为黄白色,非梗死区为砖红色。超声心动图测定左室前壁增厚率及左心室射血分数,原位末端脱氧核苷酸转移酶介导的生物素脱氧尿嘧啶核苷酸缺口末端标记法(TUNEL)检测梗死区心肌组织凋亡细胞数,行caspase3活性测定。结果TTC染色示左室前壁及部分前间隔染色为黄白色,其余区域为砖红色。实验组冠脉结扎后10min,左室前壁增厚率降低,与对照组比较有显著性差异(P<0.05)。左心室射血分数未发生明显改变,与对照组比较无显著性差异(P>0.05)。冠脉结扎后30min至60min,前壁增厚率降低与左心室射血分数进一步下降,与对照组比较有非常显著性差异(P<0.01)。实验组冠脉结扎后10min,梗死区心肌TUNEL阳性细胞数与对照组比较无显著性差异;冠脉结扎后30min至60min,梗死区心肌TUNEL阳性细胞数明显增加,与对照组比较有非常显著性差异(P<0.01)。实验组冠脉结扎后10min,梗死区心肌caspase3荧光值升高,与对照组比较有显著性差异(P<0.05)。30min至60min梗死区心肌caspase3荧光值明显升高,与对照组比较有非常显著性差异(P<0.01)。结论急性心肌缺血后早期,促凋亡基因caspase3激活,缺血心肌细胞凋亡可能为急性心肌缺血的早期病理改变,并且与心肌室壁动度与左室收缩功能降低有一定关系。