Department of Transfusion Medicine, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, China.
School of Life Sciences, Shanghai University, Shanghai, China.
Clin Transl Med. 2021 Mar;11(3):e373. doi: 10.1002/ctm2.373.
Blood transfusion, a common basic supporting therapy, can lead to acute hemolytic transfusion reaction (AHTR). AHTR poses a great risk to patients through kidney function damage in a short time. Previous reports found that heme from destroyed red blood cells impaired kidney function, and NLR family pyrin domain containing 3 (NLRP3) inflammasome was augmented in case of kidney injury. However, the detailed mechanism regarding whether NLRP3 inflammasome is involved in kidney function injury in AHTR is not fully understood yet.
Hemolysis models were established by vein injection with human blood plasma or mouse heme from destroyed red blood cells. The injured renal tubular epithelial cells (RTECs) were evaluated by tubular damage markers staining in hemolysis models and in primary RTECs in vitro. The activation of NLRP3 inflammasome in RTECs by hemes was investigated by Western blot, ELISA, scanning electron microscopy, immunofluorescent staining, flow cytometry, and hemolysis models. NLRP3 gene knockout mice were employed to confirm these observations in vitro and in vivo. The binding between a novel inhibitor (66PR) and NLRP3 was affirmed by molecule docking and co-immunoprecipitation. The rescue of 66PR on kidney function impairment was explored in murine hemolysis models.
We found that heme could activate NLRP3 inflammasome in RTECs to induce kidney function injury. NLRP3 gene knockout could prevent the damage of RTECs caused by hemes and recover kidney function in AHTR. Moreover, NLRP3 inflammasome chemical inhibitor, 66PR, could bind to NLRP3 protein and inhibit inflammasome activation in RTECs, which consequently relieved the injury of RTECs caused by hemes, and alleviated kidney function damage in the AHTR model.
Hemes could activate NLRP3 inflammasome in RTECs, and a novel NLRP3 inflammasome inhibitor named 66PR relieved kidney function damage in AHTR. Our findings provided a new possible strategy to treat kidney function failure in AHTR.
输血是一种常见的基本支持疗法，但会导致急性溶血性输血反应（AHTR）。AHTR 会在短时间内通过损害肾功能对患者造成极大的风险。先前的报告发现，破坏的红细胞中的血红素损害了肾功能，并且在肾脏损伤的情况下，NLR 家族富含吡啶结构域的 3（NLRP3）炎性小体增加。然而，关于 NLRP3 炎性小体是否参与 AHTR 中的肾功能损伤的详细机制尚不完全清楚。
通过静脉注射人血浆或从破坏的红细胞中提取的血红素来建立溶血模型。通过溶血模型和体外原代肾小管上皮细胞（RTEC）中肾小管损伤标志物染色来评估受损的 RTEC。通过 Western blot、ELISA、扫描电子显微镜、免疫荧光染色、流式细胞术和溶血模型来研究血红素在 RTEC 中对 NLRP3 炎性小体的激活作用。使用 NLRP3 基因敲除小鼠在体外和体内证实这些观察结果。通过分子对接和共免疫沉淀证实新型抑制剂（66PR）与 NLRP3 之间的结合。在鼠溶血模型中探索了 66PR 对肾功能损害的挽救作用。
我们发现血红素可以激活 RTEC 中的 NLRP3 炎性小体，导致肾功能损伤。NLRP3 基因敲除可以防止血红素引起的 RTEC 损伤并恢复 AHTR 中的肾功能。此外，NLRP3 炎性小体化学抑制剂 66PR 可以与 NLRP3 蛋白结合并抑制 RTEC 中的炎性小体激活，从而减轻血红素引起的 RTEC 损伤，并缓解 AHTR 模型中的肾功能损害。
血红素可以激活 RTEC 中的 NLRP3 炎性小体，一种新型的 NLRP3 炎性小体抑制剂 66PR 减轻了 AHTR 中的肾功能损害。我们的研究结果为治疗 AHTR 中的肾功能衰竭提供了一种新的可能策略。
