NLRP1在异基因造血干细胞移植后非感染性肺损伤中的作用

The function of NLRP1 in noninfectious pulmonary injury following allogeneic hematopoietic stem cell transplantation

【摘要】目的探索核苷酸结合寡聚化结构域样受体1（NLRP1）在异基因造血干细胞移植（allo-HSCT）后非感染性肺损伤中的作用。方法以C57BL／6小鼠和NLRP1^-/-小鼠为受鼠，建立allo-HSCT模型，流式细胞术检测骨髓嵌合率，HE染色后在高倍镜下观察NLRP1敲除前后不同时间点C57BL／6小鼠肺组织病理学形态，采用Westernblot法检测NLRP1敲除前后肺组织NLRP1及相关炎性蛋白表达情况。结果①allo-HSCT后第14天，供鼠造血干细胞基本完全植入，嵌合率均大于96％。②显微镜下观察示移植后小鼠肺组织出现严重损伤，可见明显的肺泡壁增厚，伴肺泡中出现渗出物及炎性细胞浸润。该损伤在移植后21d内呈进行性加重，而至移植后第28天，上述病理改变则逐渐减轻。移植后NLRP1敲除组小鼠在对应时间点肺泡增厚程度、肺泡内渗出及细胞浸润均轻于非敲除组小鼠。③与正常对照组比较，移植组NLRPI及NLRP1下游的相关炎性蛋白p20、Mature—IL-1B、Mature-IL-18表达逐渐增高，移植后第21天达到最高，不同时间点移植组问比较差异均有统计学意义（P值均〈0．05），与病理学改变同步。@NLRP1敲除组小鼠中性粒细胞及巨噬细胞的标志蛋白MPO、p20、Mature—IL-1p及Mature-IL-18在同-时间点的表达低于非敲除组，差异均有统计学意义（P值均〈0．05）。结论allo—HSCT后小鼠出现非感染性肺损伤并伴NLRP1表达增高，敲除NLRP1可减轻移植后肺损伤及相关炎性蛋白表达，提示NLRP1可能是移植后非感染性肺损伤的因素之-。

Objective To explore the function of NLRP1 in noninfectious pulmonary injury （nonIPI） after allogeneic stem cell transplantation （allo-HSCT）. Methods In this study, we established the model of allo-HSCT with C57BL/6 and NLRP^-/- mouse as recipients. Chimera rate was measured by flow cytometry. The HE staining was used to observe the pathology changes in the lungs. NLRP1 and relevant inflammatory proteins were measured by Western Blot. Results On the day 14 after allo-HSCT, the chimera rate was more than 96%, HSCs of donors had been successfully transplanted into recipients. HE staining showed that nonIPI occurred after allo-HSCT. The degrees of injuries reached the peak on day 21. In addition, the expressions of MPO, NLRP1, p20, Mature-IL-1β and Mature- IL-18 had same tends with the degrees of nonIPI. When we knocked out NLRP1 gene of recipients, the degrees of nonIPI reduced and the expressions of MPO, p20, Mature-IL-1 ~3 and Mature-IL-18 were less than in non-knockout group. Conclusion allo-HSCT could cause nonlPI and high expressions of MPO, p20, IL-113, IL-18, NLRP1. Knocking out NLRP1 gene could alleviate the degrees of nonIPI and reduce the expressions of relevant inflammatory proteins, indicating that NLRP1 might he one of factors contributed to nonlPI after allo- HSCT.