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目的:探讨人诱导多能间充质干细胞来源外泌体（iMSC-Exos）对肺泡巨噬细胞（AM）焦亡的作用及机制。方法:通过旋转超滤法提取人诱导多能间充质干细胞（iMSC）培养上清液中的外泌体，并利用透射电镜、蛋白质免疫印迹试验（Western blotting）、高分辨率可调电阻脉冲对提取的外泌体进行鉴定。体外培养大鼠AM细胞株NR8383，取对数生长期细胞分为3组：对照组在AM上清液中加入等量磷酸盐缓冲液（PBS）；脂多糖/三磷酸腺苷（LPS/ATP）组AM经500 μg/L的LPS刺激23 h后再加入5 mmol/L的ATP刺激1 h诱导细胞焦亡；iMSC-Exos组将100 mg/L iMSC-Exos与NR8383细胞共孵育3 h后再给予LPS和ATP刺激。采用细胞增殖与毒性检测试剂盒（CCK-8）和乳酸脱氢酶（LDH）分析检测细胞毒活性；采用免疫荧光法观察细胞凋亡和天冬氨酸特异性半胱氨酸蛋白酶-1（caspase-1）表达；采用酶联免疫吸附试验（ELISA）检测AM释放炎性因子白细胞介素（IL-1β、IL-18）水平；采用Western blotting法检测NOD样受体蛋白3（NLRP3）炎症小体途径及焦亡相关蛋白消皮素D（GSDMD）表达。结果:提取的外泌体经透射电镜观察为圆形囊泡，Western blotting显示外泌体标志物CD63、CD9呈阳性表达，高分辨率可调电阻脉冲检测显示粒子平均直径130 nm，提示外泌体提取成功，能被AM吞噬。与对照组相比，LPS和ATP刺激后，细胞活性下降〔（0.56±0.05）%比（1.06±0.07）%，n P<0.01〕，坏死物质LDH释放增加（U/L：1 218.86±22.73比188.30±1.61，n P<0.01），炎性因子分泌增加〔IL-1β（ng/L）：958.91±32.78比194.63±5.14，IL-18（ng/L）：870.89±21.86比288.85±24.48，均n P<0.01〕，细胞凋亡率〔（55.35±6.19）%比（12.01±1.32）%，n P<0.01〕及caspase-1表达均升高（荧光强度：41.06±3.65比2.80±0.54，n P<0.01），提示LPS联合ATP可成功诱导细胞焦亡。与LPS/ATP组相比，给予iMSC-Exos预处理后，AM活性增加〔（0.81±0.05）%比（0.56±0.05）%，n P<0.01〕，LDH释放减少（U/L：535.05±42.55比1 218.86±22.73，n P<0.01），炎性因子分泌减少〔IL-1β（ng/L）：381.82±19.50比958.91±32.78，IL-18（ng/L）：533.77±31.54比870.89±21.86，均n P<0.01〕，细胞凋亡率〔（19.74±2.96）%比（55.35±6.19）%，n P<0.01〕和caspase-1表达均下降（荧光强度：12.16±1.31比41.06±3.65，n P<0.01），同时NLRP3炎症小体途径及焦亡相关蛋白GSDMD表达水平受到显著抑制〔NLRP3蛋白（NLRP3/β-actin）：0.62±0.06比1.89±0.11，活化的caspase-1蛋白（cleaved caspase-1/β-actin）：0.42±0.07比1.22±0.17，GSDMD蛋白（GSDMD/β-actin）：0.57±0.05比1.22±0.05，均n P<0.01〕。n 结论:iMSC-Exos抑制了LPS/ATP诱导的AM焦亡和炎性因子表达，可能与靶向抑制NLRP3炎症小体途径有关，提示iMSC-Exos能抑制AM焦亡，发挥抗炎效应。“,”Objective:To investigate the effect and mechanism of exosomes derived from human-induced pluripotent mesenchymal stem cells (iMSC-Exos) on alveolar macrophages (AM) pyroptosis.Methods:The exosomes in the culture supernatant of human-induced pluripotent mesenchymal stem cells (iMSC) were extracted by rotating ultrafiltration, and the extracted exosomes were identified by transmission electron microscopy, Western blotting and high-resolution adjustable resistance pulse. The rat alveolar macrophage cells (NR8383 cells) were cultured n in vitro and the logarithmic growth phase cells were divided into three groups: the control group was added with an equal volume of phosphate buffered saline (PBS) in the AM supernatant; in LPS/ATP group AM cells were stimulated with 500 μg/L LPS for 23 hours and then 5 mmol/L ATP was added for 1 hour to induce pyrolysis; iMSC-Exos group was incubated with AM and 100 mg/L iMSC-Exos for 3 hours before giving LPS and ATP. The cytotoxic activity was detected by cell counting kit-8 (CCK-8) and lactate dehydrogenase (LDH) analysis, the apoptosis and the expression of caspase-1 were observed by immunofluorescence, the levels of inflammatory factors interleukins (IL-1β and IL-18) released by AM were detected by enzyme linked immunosorbent assay (ELISA), the NOD-like receptor protein 3 (NLRP3) inflammasome pathway and the expression level of pyroptosis related protein gasdermin D (GSDMD) were detected by Western blotting.n Results:The extracted exosomes were observed by transmission electron microscopy as round vesicles, expressing exosomal markers CD63 and CD9 showed by Western blotting, high-resolution adjustable resistance pulse showed the average diameter of the particles was 130 nm, and could be uptaken by AM. Compared with the control group, the cell activity decreased [(0.56±0.05)% vs. (1.06±0.07)%, n P < 0.01], the release of necrotic substance LDH increased (U/L: 1 218.86±22.73 vs. 188.30±1.61, n P < 0.01), the expression levels of inflammatory factors increased [IL-1β (ng/L): 958.91±32.78 vs. 194.63±5.14, IL-18 (ng/L): 870.89±21.86 vs. 288.85±24.48, both n P < 0.01], and the apoptosis rate [(55.35±6.19)% vs. (12.01±1.32)%, n P < 0.01] and caspase-1 expression (fluorescence intensity: 41.06±3.65 vs. 2.80±0.54, n P < 0.01) elevated in the AM after LPS/ATP stimulation, suggesting that LPS combined with ATP successfully induced alveolar pyroptosis. Compared with the LPS/ATP group, AM pretreated with iMSC-Exos showed increased cell viability [(0.81±0.05)% vs. (0.56±0.05)%, n P < 0.01], decreased LDH secretion (U/L: 535.05±42.55 vs. 1 218.86±22.73, n P < 0.01), decreased expression of inflammatory factors [IL-1β (ng/L): 381.82±19.50 vs. 958.91±32.78, IL-18 (ng/L): 533.77±31.54 vs. 870.89±21.86, both n P < 0.01], and decreased apoptosis rate [(19.74±2.96)% vs. (55.35±6.19)%, n P < 0.01] and caspase-1 expression (fluorescence intensity: 12.16±1.31 vs. 41.06±3.65, n P < 0.01). At the same time, the expression of NLRP3 inflammasome pathway [NLRP3 protein (NLRP3/β-actin): 0.62±0.06 vs. 1.89±0.11; cleaved caspase-1 protein (cleaved caspase-1/β-actin): 0.42±0.07 vs. 1.22±0.17, both n P < 0.01] and pyrolysis-related protein was significantly inhibited [GSDMD protein (GSDMD/β-actin): 0.57±0.05 vs. 1.22±0.05, n P < 0.01].n Conclusion:iMSC-Exos successfully reversed the AM pyroptosis and inflammatory factor expression induced by LPS/ATP, which may be due to the targeted inhibition of NLRP3 inflammasome pathway, suggesting that iMSC-Exos can exert anti-inflammatory effects by inhibiting the pyrolysis of AM.