The Immunological Effect of Oxygen Carriers on Normothermic Ex Vivo Liver Perfusion.
The Immunological Effect of Oxygen Carriers on Normothermic Ex Vivo Liver Perfusion.
复制标题
DOI：
10.3389/fimmu.2022.833243
复制
发表时间：
2022
影响因子：
7.3
通讯作者：
中科院分区：
文献类型：
--
作者：
常温离体肝灌注（NEVLP）是一种器官保存方法，可在移植前进行移植肝功能评估。常温灌注溶液的一个关键组分是氧载体，以向肝脏提供氧气以维持代谢活动。在NEVLP期间，氧载体如红细胞（RBC）或基于血红蛋白的氧载体对肝脏驻留的免疫细胞具有未知的影响。在这项研究中，我们评估了不同的氧载体对肝脏驻留免疫细胞的表型和功能的影响。成年刘易斯大鼠肝脏使用三种不同的氧载体进行NEVLP：人包装红细胞（pRBC），大鼠pRBC，或氧珠蛋白（一种合成的血红蛋白氧载体）。收集每小时灌注液样品用于下游分析，并消化肝脏以分离免疫细胞。测定灌流液中常见细胞因子的浓度，并采用流式细胞术和定量逆转录聚合酶链反应（qRT-PCR）对免疫细胞进行表型表征。使用混合淋巴细胞反应评估肝脏驻留免疫细胞的刺激功能。三种氧载体之间在肝功能、肝损伤或组织学方面没有差异。qRT-PCR显示，与未处理组相比，人pRBC组中活化B细胞核因子κ轻链增强子（NF-κ B）、白细胞介素（IL-1β）、C-C基序趋化因子配体2（CCL 2）、C-C基序趋化因子配体7（CCL 7）和CD 14的基因表达显著上调，而大鼠pRBC和Oxyglobin组与未处理组无差异。流式细胞术表明，与氧珠蛋白相比，免疫共刺激蛋白CD 86的细胞表面表达在用人pRBC灌注的肝脏驻留巨噬细胞和浆细胞样树突状细胞上显著更高。混合淋巴细胞反应显示，与氧珠蛋白组相比，人和大鼠pRBC组的同种异体T细胞增殖增加。肝驻留免疫细胞是移植后排斥反应的重要介质。在这项研究中，我们表明NEVLP溶液中使用的氧载体可以影响这些肝脏驻留免疫细胞的表型。与人或大鼠pRBC相比，合成的基于血红蛋白的氧载体Oxyglobin显示出最少量的肝脏驻留免疫细胞活化和最少量的同种异体增殖。为了减轻NEVLP（和随后的移植）期间肝脏驻留的免疫细胞活化，氧珠蛋白可能是最佳的氧载体。
Normothermic ex vivo liver perfusion (NEVLP) is an organ preservation method that allows liver graft functional assessment prior to transplantation. One key component of normothermic perfusion solution is an oxygen carrier to provide oxygen to the liver to sustain metabolic activities. Oxygen carriers such as red blood cells (RBCs) or hemoglobin-based oxygen carriers have an unknown effect on the liver-resident immune cells during NEVLP. In this study, we assessed the effects of different oxygen carriers on the phenotype and function of liver-resident immune cells. Adult Lewis rat livers underwent NEVLP using three different oxygen carriers: human packed RBCs (pRBCs), rat pRBCs, or Oxyglobin (a synthetic hemoglobin-based oxygen carrier). Hourly perfusate samples were collected for downstream analysis, and livers were digested to isolate immune cells. The concentration of common cytokines was measured in the perfusate, and the immune cells underwent phenotypic characterization with flow cytometry and quantitative reverse transcription polymerase chain reaction (qRT-PCR). The stimulatory function of the liver-resident immune cells was assessed using mixed lymphocyte reactions. There were no differences in liver function, liver damage, or histology between the three oxygen carriers. qRT-PCR revealed that the gene expression of nuclear factor κ light chain enhancer of activated B cells (NF-kB), Interleukin (IL-1β), C-C motif chemokine ligand 2 (CCL2), C-C motif chemokine ligand 7 (CCL7), and CD14 was significantly upregulated in the human pRBC group compared with that in the naive, whereas the rat pRBC and Oxyglobin groups were not different from that of naive. Flow cytometry demonstrated that the cell surface expression of the immune co-stimulatory protein, CD86, was significantly higher on liver-resident macrophages and plasmacytoid dendritic cells perfused with human pRBC compared to Oxyglobin. Mixed lymphocyte reactions revealed increased allogeneic T-cell proliferation in the human and rat pRBC groups compared to that in the Oxyglobin group. Liver-resident immune cells are important mediators of rejection after transplantation. In this study, we show that the oxygen carrier used in NEVLP solutions can affect the phenotype of these liver-resident immune cells. The synthetic hemoglobin-based oxygen carrier, Oxyglobin, showed the least amount of liver-resident immune cell activation and the least amount of allogeneic proliferation when compared to human or rat pRBCs. To mitigate liver-resident immune cell activation during NEVLP (and subsequent transplantation), Oxyglobin may be an optimal oxygen carrier.