分析肝移植术后受者外周血CD19⁺CD24^hiCD38^hi B细胞占单个核细胞比例变化情况及其与急性细胞性排斥反应(ACR)之间的关系。

回顾性分析2013年12月至2015年12月在浙江大学医学院附属第一医院接受心脏死亡器官捐献肝移植的80例成人受者临床资料，根据术后是否发生ACR，将受者分为ACR组(25例)和非ACR组(55例)。术前、术后各个时间点抽取参加研究者静脉血并分离外周血单个核细胞，加入异硫氰酸荧光素-单克隆鼠抗人CD19抗体、藻红蛋白-单克隆鼠抗人CD24抗体和别藻蓝蛋白-单克隆鼠抗人CD38抗体，流式细胞仪检测各组CD19⁺CD24^hiCD38^hi B细胞百分比。采用t检验和单因素方差分析比较正态分布计量资料，采用χ²检验比较计数资料，采用Kaplan-Meier法绘制受试者工作特征曲线(ROC曲线)。P<0.05为差异有统计学意义。

ACR组、非ACR组受者术前外周血平均CD19⁺CD24^hiCD38^hi B细胞比例分别为(3.13±0.91)%、(3.49±0.83)%，差异无统计学意义(t＝1.636，P>0.05)。ACR组术后发生ACR前外周血平均CD19⁺CD24^hiCD38^hi B细胞比例为(1.87±0.70)%。非ACR组受者术后3个月、6个月和1年外周血平均CD19⁺CD24^hiCD38^hi B细胞比例分别为(1.64±0.52)%、(1.63±0.56)%和(2.04±1.24)%，术后3、6个月平均值均低于术前和术后1年，差异均有统计学意义(P均<0.05)。ACR组受者发生ACR时外周血平均CD19⁺CD24^hiCD38^hi B细胞比例为(0.8±0.5)%，低于发生ACR前的平均水平(t＝5.752，P<0.05)，且低于非ACR组术后3个月、6个月和1年的平均水平(P<0.05)。ACR组受者接受抗排斥反应治疗后，CD19⁺CD24^hiCD38^hi B细胞比例也逐渐增加，ACR发生后7 d为(0.84±0.08)%，与ACR发生时相比差异无统计学意义(P>0.05)；而发生30 d后达(1.65±0.18)%，与ACR发生时相比差异有统计学意义(P<0.05)。当截断值为1.015%时，CD19⁺CD24^hiCD38^hi B细胞比例预测ACR发生的敏感度和特异度分别为0.786和0.702，ROC曲线下面积为0.775(95%CI: 0.671~0.879，P<0.05)。

CD19⁺CD24^hiCD38^hi B细胞比例下降与肝移植术后ACR反应发生有关，并可作为预测ACR发生的细胞标志物。

To analyze the proportion change of CD19⁺ CD24^hiCD38^hi B cells to mononuclear cells in peripheral blood of liver transplant recipients and its relationship with acute cellular rejection (ACR) after liver transplantation.

The clinical data of 80 adult recipients of liver transplantation after cardiac death donation in the First Affiliated Hospital of Zhejiang University School of Medicine from 2013 to 2015 were retrospectively analyzed. According to the occurrence of ACR, the recipients were divided into ACR group (25 cases) and non-ACR group (55 cases). The venous blood of the participants was collected and the peripheral blood mononuclear cells were isolated. FITC-monoclonal mouse anti-human CD19 antibody, PE-monoclonal mouse anti-human CD24 antibody and APC-monoclonal mouse anti-human CD38 antibody were added. The percentage of CD19⁺ CD24^hiCD38^hi B cells in each group was detected by flow cytometry. The measurement data conforming to normal distribution were compared by group t test or one-way ANOVA, the counting data were compared by chi-square test, and Kaplan-Meier method was used to draw the receiver operating characteristic curve. A P<0.05 was considered statistically significant.

The pre-operative average proportion of CD19⁺ CD24^hiCD38^hi B cells in peripheral blood of ACR group [(3.13±0.91)%] and non-ACR group [(3.49±0.83)%] had no significantly difference (t=1.636, P>0.05). The average proportion of CD19⁺ CD24^hiCD38^hi B cells in peripheral blood before ACR was (1.87±0.70)% in ACR group. The percentages of CD19⁺ CD24^hiCD38^hi B cells in non-ACR group were (1.64±0.52)%, (1.63±0.56)% and (2.04±1.24)% respectively at 3, 6 months and 1 year after liver transplantation, and the mean values at 3 and 6 months after liver transplantation were lower than those before surgery and 1 year after liver transplantation (P<0.05). The average proportion of CD19⁺ CD24^hiCD38^hi B cells in peripheral blood of ACR group was (0.8±0.5)% on the time of ACR, which lower than the average level before ACR (t=5.752, P<0.05), and also lower than the average level of 3, 6 months and 1 year after operation of non-ACR group ( P<0.05). In addition, the proportion of CD19⁺ CD24^hiCD38^hi B cells was increased in the ACR group after receiving anti-rejection treatment. The average proportion of CD19⁺ CD24^hiCD38^hi B cells was (0.84±0.08)% at 7 days after treatment, which had no statistical significance with the level when the ACR occurred (P>0.05), but the difference between 30 days after treatment [(1.65±0.18)%] and the level when the ACR occurred had statistical significance (P<0.05). When the cut-off value was 1.015%, the sensitivity and specificity of CD19⁺ CD24^hiCD38^hi B cells frequency for predicting the occurrence of ACR were 0.786 and 0.702, respectively. The area under the curve was 0.775 (95%CI: 0.671-0.879, P<0.05).

The decreased frequency of CD19⁺ CD24^hiCD38^hi B cells is associated with the occurrence of ACR after liver transplantation, and could be served as a cellular marker for predicting the occurrence of ACR.