卵巢癌细胞通过P38 MAPK通路促进CD8~+调节T细胞的生成

目的探讨丝裂原活化蛋白激酶(MAPK)信号通路在卵巢癌细胞(SKOV3)诱导CD8+Treg分化过程中的作用。方法建立SKOV3与健康人CD8+T细胞体外共培养体系,设置CD8+T细胞单独培养组为对照组。共培养5 d后,收集各组CD8+T细胞,荧光定量PCR和流式细胞术检测CD8+T细胞中Treg相关标志物(CD25、Foxp3、CD28)的表达率;功能抑制试验检测两组CD8+T细胞对nave CD4+T细胞增殖能力的影响;Western blot检测MAPK通路相关蛋白(ERK/p-ERK、JNK/p-JNK、P38 MAPK/p-P38 MAPK)的表达水平;P38 MAPK特异性抑制剂SB203580预处理CD8+T细胞后,评价CD8+T细胞中Treg相关标志物(CD25、Foxp3、CD28)的表达变化。结果共培养组CD8+T细胞中CD25及Foxp3表达率均显著高于对照组(P0.05),CD28表达率显著低于对照组(P0.05);共培养组CD8+T细胞相比对照组,抑制nave CD4+T细胞的增殖力增强;Western blot结果显示,共培养组p-P38 MAPK的表达水平显著高于对照组(P0.05),SB203580预处理后CD8+T细胞中Treg相关标志物表达率均下调。结论卵巢癌细胞通过活化CD8+T细胞的P38 MAPK信号通路诱导具有抑制作用的CD8+Treg的生成,促进肿瘤进展。     

P38MAPK、Caspase-8在Fas—AD诱导Bel-7402细胞凋亡中的作用

目的通过P38MAPK抑制剂SB203580及caspase-8抑制剂Ac-IEFD-cho的作用,确定P38MAPK、caspase-8的相互作用关系,进一步揭示Fas—AD诱导Bel-7402细胞凋亡的信号转导机制。方法通过RT—PCR法检测培养的Bel-7402细胞中P38MAPK mRNA、caspase．8 mRNA在Fas．AD、SB203580及Ac—IEFD—cho作用下的表达情况。结果在Fas-AD诱导Bel-7402细胞凋亡中,SB203580和Ac—IEFD—cho能分别抑制p38MAPK mRNA、caspase-8 mRNA的表达。结论在Bel-7402细胞凋亡中,P38MAPK与easpase-8参与Fas—AD凋亡途径,并且在mRNA水平进行相互调节。     

p38 MAPK在顺铂诱导肾小管上皮细胞凋亡中的作用

目的:探讨p38 MAPK在顺铂诱导大鼠近端肾小管上皮细胞(RPTC)凋亡中的作用。方法:首先采用Western blot实验检测0、5、10和20μmol/L顺铂处理24 h对细胞凋亡的影响,确定最佳处理剂量;而后采用20μmol/L顺铂联合50 mg/L p38 MAPK抑制剂SB203580刺激RPTC,实验分为对照组、顺铂组及顺铂+SB203580(加入SB203580处理RPTC 1 h后再给予顺铂处理24 h)。采用相差荧光显微镜观察和流式细胞术分析顺铂处理后RPTC的凋亡情况;采用Ac-DEVD-AFC试剂盒检测RPTC裂解液中的caspase活性;Western blot实验检测p38、磷酸化p38、cleaved PARP和cleaved caspase-3等的蛋白水平;pH计检测顺铂处理后RPTC外环境pH值改变。结果:20μmol/L顺铂处理RPTC 24 h,可以明显诱导细胞凋亡;顺铂处理15 min后RPTC中p38 MAPK开始磷酸化并达到高峰。顺铂处理后12.08%的RPTC呈凋亡形态,具有增强的caspase活性,并且cleaved PARP和cleaved caspase-3水平明显升高(P0.05);p38 MAPK抑制剂SB203580可抑制p38的磷酸化,降低RPTC的凋亡率和caspase活性,并减少cleaved PARP和cleaved caspase-3的蛋白水平。同时,SB203580可逆转顺铂诱导的RPTC培养基pH值的改变。结论:p38 MAPK的磷酸化在顺铂诱导的RPTC凋亡中发挥作用。顺铂诱导RPTC凋亡后,可改变细胞外酸性环境,并可被p38 MAPK抑制剂SB203580所抑制。     

Manumycin诱导细胞凋亡抑制乳腺癌细胞SK-BR-3活性

目的:研究manumycin对乳腺癌腹腔转移癌细胞株SK-BR-3的抑癌效应及其诱导凋亡。方法:用MTT法检测manumycin对SK-BR-3细胞的抑癌作用。免疫印迹方法检测p38 MAPK蛋白表达。用caspase-3活性检测试剂盒定量检测manumycin诱导细胞凋亡的水平及评估特异性的p38 MAPK抑制剂SB203580对凋亡的影响。结果:经6 μmol/L、18 μmol/L、54 μmol/L manumycin处理SK-BR-3细胞24 h时,其抑制率分别为(7.4±3.9)%、(21.0±4.4)%和(64.7±4.1)%,呈量效关系。其中后2者的细胞活性与对照组比有显著差异(P<0.01)。用药24 h的IC₅₀为42.5 μmol/L。同时此药物可明显增加caspase-3的活性,且这一效应可部分地被p38抑制剂SB203580阻断。免疫印迹结果显示manumycin促进p38的磷酸化。结论:manumycin可通过诱导SK-BR-3细胞凋亡而产生抑癌作用,p38 MAPK是manumycin诱导细胞凋亡的通路之一。     

p38MAPK参与千金藤素诱导的心肌细胞凋亡

目的: 探讨千金藤素(CEP)致Sprague-Dawley(SD)乳大鼠心肌细胞的凋亡作用及其信号途径。方法: 应用MTT法检测千金藤素对心肌细胞活性的抑制作用;利用Hoechst 33342染色及Western blotting方法检测凋亡相关信号分子caspase-3,观察CEP致心肌细胞凋亡的作用;采用Western blotting法观测 CEP对有丝分裂原活化蛋白激酶(MAPKs)家族3个主要信号分子c-Jun氨基端激酶(JNK)、细胞外信号调节激酶(ERK)、p38 MAPK磷酸化水平的影响,并利用ERK和p38 MAPK的特异性抑制剂,分别验证两种分子所介导的信号通路在CEP致心肌细胞凋亡中的作用。结果: (1)CEP能够剂量依赖和时间依赖地抑制心肌细胞的活性。(2)CEP作用于心肌细胞,出现细胞核碎裂现象和caspase-3激活。(3)CEP作用下p38 MAPK和ERK磷酸化水平显著增强,JNK的磷酸化状态未发生显著改变。(4)p38 MAPK磷酸化抑制剂SB203580显著减轻CEP对心肌细胞活性的抑制作用;ERK磷酸化抑制剂PD98059不能影响CEP对心肌细胞活性的抑制作用。结论: p38 MAPK参与CEP致心肌细胞凋亡作用。     

p38MAPK信号传导通路在人绒毛滋养层细胞EMMPRIN表达和体外侵袭中的作用

目的 研究人绒毛滋养层细胞中调节细胞外基质金属蛋白酶诱导因子（EMMPRIN）表达的信号通路及p38MAPK信号通路在滋养细胞体外侵袭中的作用.方法 体外无血清培养人绒毛滋养细胞,分别加入p38MAPK抑制剂（SB203580）,JNK抑制剂（SP600125）,ERK抑制剂（PD098059）,用RT-PCR及Western blot方法观察阻断剂对EMMPRIN表达的影响.用不同浓度的佛波酯（PMA）作用于滋养细胞,ELISA方法检测滋养细胞中p38MAPK的活性变化,用transwell细胞侵入系统检测滋养细胞的侵袭作用;加入不同浓度的SB203580,观察阻断剂对滋养细胞侵袭性的影响.结果 JNK抑制剂、ERK抑制剂对滋养细胞分泌EMMPRIN无影响,p38MAPK抑制剂以时间剂量依赖的方式抑制滋养细胞表达EMMPRIN,SB203580浓度为5、10、15及20μmol/L作用24h后,EMMPIRN的抑制率分别为7.3%、24.6%、31.8%及39%;加入10μmol/L的SB203580培养24h后即可抑制EMMPRIN基因和蛋白的表达,抑制率为22%,培养48h和72h抑制率分别为45%和76%.向培养的细胞中加入浓度为0.1、1、10mmol/L的PMA作用30min,PMA以时间剂量依赖的方式激活p38MAPK,而SB203580以时间剂量依赖的方式抑制PMA对p38MAPK的激活.PMA可以促进滋养细胞体外侵袭作用,5mmol/L的SB203580能明显的抑制滋养细胞的体外侵袭能力,也能抑制PMA对滋养细胞侵袭活性的激活.结论 p38MAPK信号传导途径参与了人绒毛滋养细胞中EMMPRIN的表达.p38MAPK通路在人滋养细胞的侵袭行为中有重要的作用,p38MAPK激动剂可能会为子痫前期-子痫的防治提供新的途径.     

p38 MAPK信号途径参与大鼠系膜细胞MMP2表达

目的探讨系膜细胞中调节MMP2表达的信号通路。方法鼠系膜细胞培养,分别加入酪氨酸激酶抑制剂（Herbimycin A）,p38MAPK抑制剂（SB203580）,MEK抑制剂（U0126）,ERK抑制剂（PD098059）,P13K抑制剂（Y294002）,用酶谱法分析MMP2酶活性、用RT-PCR及Westem方法从基因及蛋白水平,观察阻断剂对MMP2表达的影响。结果酪氨酸激酶抑制剂、MEK抑制剂、ERK抑制剂及P13K抑制剂对MMP2酶活性、mRNA及蛋白水平无影响,在72hp38MAPK抑制剂SB203580抑制MMP2活性25％。在48h当SB203580浓度分别为10、20、30及40μmol／L时,系膜细胞中MMP2的抑制率分别为7．2％、13．5％、21．3％及28％。结论大鼠系膜细胞中p38MAPK信号传导途径参与了MMP2的表达,并且p38MAPK抑制剂SB203580对MMP2的抑制有剂量依赖性。     

Manumycin通过诱导细胞凋亡抑制人胰腺导管癌细胞Panc-1活性

目的：观察manumycin对人胰腺导管癌细胞Panc-1的抑制效应，并探讨其诱导细胞凋亡是否经p38MAPK介导。 方法： 用MTT法检测manumycin对Panc-1细胞的抑癌作用。用caspase-3活性检测试剂盒定量检测manumycin诱导细胞凋亡的水平及评估特异性的p38MAPK抑制剂SB203580对它的影响。 结果： 经manumycin(6 μmol/L、18 μmol/L、54 μmol/L)处理Panc-1细胞24 h,对Panc-1细胞生长具有明显的抑制作用，其抑制率分别为8.9%、21.9%和67.0%，其中后二者的细胞活性与对照组相比有显著差异(P<0.01)，呈量效关系。用药24 h的IC50为34.7 μmol/L。同时，此药物可明显增加caspase-3的活性，且这一效应可部分地被p38抑制剂SB203580阻断。 结论： Manumycin可通过诱导Panc-1细胞凋亡而产生抑癌作用，p38MAPK是manumycin诱导细胞凋亡的通路之一。     

p38MAPK在非对称性二甲基精氨酸所致内皮细胞骨架改变过程中的作用

目的：探讨非对称性二甲基精氨酸（asymmetricdimethylargine,ADMA）对人脐静脉内皮细胞（humanumbilicalveinendothelialcells,HUVECs）的细胞骨架改变的影响及p38丝裂原激活蛋白激酶（p38mitogen—activatedproteinkinase,p38MAPK）在该过程中的作用。方法：体外进行HUVEC培养,实验分为正常对照组、sB203580组、ADMA组（量效关系组、时效关系组）及sB203580＋ADMA组（SB203580＋ADMA量效关系组及SB203580＋ADMA时效关系组）。对各组细胞进行免疫荧光染色,利用激光扫描共聚焦显微镜观察肌动蛋白（F-actin）形态变化,图像分析软件行F-actin荧光灰度值分析,流式细胞仪行F．actin荧光定量分析。结果：ADMA可诱导HUVECs应力纤维形成,导致F．actin荧光灰度值、荧光定量增加;而SB203580可抑制ADMA的作用。结论：ADMA可呈时间及浓度依赖性地导致细胞骨架改变。p38MAPK特异性抑制剂SB203580可抑制ADMA对内皮细胞骨架的改变,提示p38MAPK参与了ADMA所导致的HUVECs内皮细胞的骨架改变。     

MAPK信号转导途径在Mtb-Ag激活的γδT细胞杀伤肿瘤细胞中的作用

目的：探讨MAPK信号转导途径在结核杆菌抗原(Mtb-Ag)活化的γδT细胞杀伤肿瘤细胞中的作用。方法：用Mtb-Ag刺激正常人PBMC以诱导γδT细胞扩增，并用磁珠阳性分选法分离高纯度的γδT细胞；用MTT比色法测定γδT细胞对肿瘤细胞系K562和Raji的细胞毒活性，并观察MEK／Erk特异性抑制剂PD98059和p38 MAPK特异性抑制剂SB203580，对细胞毒活性的阻断作用：用流式细胞仪检测肿瘤细胞诱导γδT细胞上CD69的表达，并观察PD98059和SB203580对CD69表达的抑制作用。结果：新鲜分离的PB-MC，用Mtb-Ag刺激培养第10天，用磁珠阳性法分离的细胞中γδT细胞的比率，分别为3．56％、74．63％和98．20％。PD98059可抑制γδT细胞的杀瘤活性，且对γδT细胞杀伤Fas低表达的K562细胞的抑制率(39．27％)高于对γδT细胞杀伤高表达Fas的Raji细胞的抑制率(26．58％)。PD98059还能明显抑制肿瘤细胞诱导γδT细胞表达CD69；而SB203580对γδT细胞的杀瘤活性和肿瘤细胞诱导的CD69的表达均无影响。结论：MAPK途径中的Erk通路(而不是p38通路)参与了γδT细胞对肿瘤细胞细胞毒活性的启动，且可能对γδT细胞的颗粒外吐作用较大，而对Fas／FasL介导的细胞毒活性的作用较小。MAPK途径的Erk通路可能还参与肿瘤细胞诱导γδT细胞的活化。     

TPX2通过p38 MAPK信号通路诱导直肠癌HR-8348细胞凋亡

目的:研究下调非洲爪蟾驱动蛋白样蛋白2靶蛋白(TPX2)对直肠癌细胞凋亡的影响及机制。方法:用TPX2小干扰RNA(si RNA)转染直肠癌HR-8348细胞,记为TPX2 si RNA组;以不做转染的细胞作为正常对照(control)组;以转染si RNA阴性对照(si RNA-NC)的细胞作为si RNA-NC组;用p38 MAPK抑制剂处理敲减TPX2表达后的直肠癌HR-8348细胞记为TPX2 si RNA+SB203580组。RT-qPCR和Western blot测定TPX2的表达水平,MTT法测定细胞存活率,流式细胞术测定细胞凋亡,Western blot测定细胞中p38 MAPK、p-p38 MAPK、cleaved caspase-3和Bcl-2的蛋白水平。结果:TPX2 si RNA转染后HR-8348细胞中TPX2的m RNA和蛋白表达水平显著下降(P 0. 05),而转染si RNA-NC对HR-8348细胞中TPX2的m RNA和蛋白水平没有影响。敲减TPX2表达后的直肠癌HR-8348细胞存活率降低,凋亡率升高,细胞中的cleaved caspase-3、p-p38 MAPK/p38 MAPK蛋白水平明显升高,Bcl-2水平水平降低,与control组比较,差异有统计学意义(P 0. 05)。与TPX2 si RNA组相比,TPX2 si RNA+SB203580组的HR-8348细胞凋亡率、cleaved caspase-3水平和p-p38 MAPK/p38 MAPK蛋白水平明显降低,存活率明显升高(P 0. 05)。结论:TPX2表达下调可以通过激活p38 MAPK促进直肠癌HR-8348细胞凋亡。     

p38有丝分裂原激酶活化参与继发性脊髓损伤后神经细胞凋亡的实验研究

探索脊髓损伤(SCI)后p38有丝分裂原激酶(p38MAPK)的表达及其与神经细胞凋亡的关系。采用Allen’s法建立大鼠急性SCI动物模型,用蛋白印迹法和免疫组织化学染色方法检测SCI后p38MAPK和caspase-3表达的变化;采用实时定量PCR法检测SCI后caspase-3 mRNA的表达;用原位末端标记法(TUNEL)检测SCI后神经细胞凋亡。结果表明SCI后总p38MAPK表达无变化,但p38MAPK磷酸化明显增多,于伤后6h达高峰;伤后24hcaspase-3表达明显增加。TUNEL检测显示,伤后6h受损伤的脊髓组织有少许凋亡细胞出现,24h细胞凋亡最明显。鞘内注射p38MAPK抑制剂SB203580,明显减少caspase-3的表达,并减少细胞凋亡。以上结果显示SCI后损伤局部p38MAPK激活诱导了caspase-3基因表达,导致神经细胞凋亡;抑制p38MAPK可以阻止SCI后继发的神经细胞凋亡。     

HYPOXIA INDUCES APOPTOSIS BY CASPASE ACTIVATION ACCOMPANYING CYTOCHROME C RELEASE FROM MITOCHONDRIA IN MC3T3E1 OSTEOBLASTS. p38 MAPK IS RELATED IN HYPOXIA-INDUCED APOPTOSIS

The aim of this study is to elucidate the possible mechanism of apoptosis in response to hypoxia in MC3T3E1 osteoblasts. MC3T3E1 osteoblasts under hypoxic conditions (2% oxygen) resulted in apoptosis in a time-dependent manner estimated by DNA fragmentation assay and nuclear morphology stained with fluorescent dye, Hoechst 33258. Pretreatment with Z-VAD-FMK, a pan-caspase inhibitor, or Z-DEVD-CHO, a specific caspase-3 inhibitor, completely suppressed the DNA ladder in response to hypoxia. An increase in caspase-3-like protease (DEVDase) activity was observed during apoptosis, but no caspase-1 activity (YVADase) was detected. To confirm what caspases are involved in apoptosis, western blot analysis was performed using anticaspase-3 or -6 antibody. The 10-kDa protein, corresponding to the active products of caspase-3 and the 10-kDA protein of the active protein of caspase-6 were generated in hypoxia-challenged cells in which processing of the full length form of caspase-3 and -6 was evident. With a time course similar to this caspase-3 and -6 activation was evident, hypoxic stress caused the cleavage of lamin A, typical of caspase-6 activity. In addition, the stress elicited the release of cytochrome c into the cytosol during apoptosis. Furthermore, we have observed that pre-treatment with SB203580, a selective p38 MAP kinase (p38 MAPK) inhibitor, attenuated the hypoxia-induced apoptosis. The addition of SB203580 suppressed caspase-3 and -6-like protease activity by hypoxia up to 50%. In contrast, PD98059 had no effect on the hypoxia-induced apoptosis. To confirm the involvement of MAP kinase, JNK/SAPK, ERK, or p38 kinase assay was performed. Although p38 MAPK was activated in response to hypoxic treatment, the other MAP kinase -JNK/SAPK or ERK- was not or modestly activated. These results suggest that p38 MAPK positively regulates hypoxia-induced apoptosis in MC3T3E1 osteoblasts.     

HYPOXIA INDUCES APOPTOSIS BY CASPASE ACTIVATION ACCOMPANYING CYTOCHROME C RELEASE FROM MITOCHONDRIA IN MC3T3E1 OSTEOBLASTS. p38 MAPK IS RELATED IN HYPOXIA-INDUCED APOPTOSIS

The aim of this study is to elucidate the possible mechanism of apoptosis in response to hypoxia in MC3T3E1 osteoblasts. MC3T3E1 osteoblasts under hypoxic conditions (2% oxygen) resulted in apoptosis in a time-dependent manner estimated by DNA fragmentation assay and nuclear morphology stained with fluorescent dye, Hoechst 33258. Pretreatment with Z-VAD-FMK, a pan-caspase inhibitor, or Z-DEVD-CHO, a specific caspase-3 inhibitor, completely suppressed the DNA ladder in response to hypoxia. An increase in caspase-3-like protease (DEVDase) activity was observed during apoptosis, but no caspase-1 activity (YVADase) was detected. To confirm what caspases are involved in apoptosis, western blot analysis was performed using anticaspase-3 or -6 antibody. The 10-kDa protein, corresponding to the active products of caspase-3 and the 10-kDA protein of the active protein of caspase-6 were generated in hypoxia-challenged cells in which processing of the full length form of caspase-3 and -6 was evident. With a time course similar to this caspase-3 and -6 activation was evident, hypoxic stress caused the cleavage of lamin A, typical of caspase-6 activity. In addition, the stress elicited the release of cytochrome c into the cytosol during apoptosis. Furthermore, we have observed that pre-treatment with SB203580, a selective p38 MAP kinase (p38 MAPK) inhibitor, attenuated the hypoxia-induced apoptosis. The addition of SB203580 suppressed caspase-3 and -6-like protease activity by hypoxia up to 50%. In contrast, PD98059 had no effect on the hypoxia-induced apoptosis. To confirm the involvement of MAP kinase, JNK/SAPK, ERK, or p38 kinase assay was performed. Although p38 MAPK was activated in response to hypoxic treatment, the other MAP kinase -JNK/SAPK or ERK- was not or modestly activated. These results suggest that p38 MAPK positively regulates hypoxia-induced apoptosis in MC3T3E1 osteoblasts.     

p38 MAPK as a negative regulator of VEGF/VEGFR2 signaling pathway in serum deprived human SK-N-SH neuroblastoma cells

Evidence suggests that vascular endothelial growth factor (VEGF) mediates neuroprotection to prevent an apoptotic cell death. The p38 mitogen-activated protein kinase (MAPK) pathway is implicated as an important mediator of neuronal apoptosis but its role in VEGF-mediated neuroprotection is unclear. Herein, we show that treatments with the p38 MAPK inhibitor, SB202190, enhanced VEGF-mediated survival in serum deprived SK-N-SH neuroblastoma cells by decreasing caspase-3/7 activation while increasing the phosphorylation of the extracellular signal-regulated kinase (ERK1/2) and Akt signaled through the VEGF receptor, VEGFR2. A blockade of VEGFR2 signaling with a selective inhibitor, SU1498 or gene silencing with VEGFR2 siRNA in SB202190 treated cells abrogated this prosurvival response and induced high activation levels of caspase-3/7. These findings suggested that the protection elicited by p38 MAPK inhibition in serum starved cells was dependent on a functional VEGF/VEGFR2 pathway. However, p38 MAPK inhibition attenuated caspase-3 cleavage in SU1498/SB202190 treated cells, indicating that p38 MAPK and caspase-3 only contributed in part to the total levels of caspase-3/7 induced by VEGFR2 inhibition. Pretreatments with the pan caspase inhibitor, z-VAD-fmk, prevented the apoptosis induced by VEGFR2 inhibition and promoted survival in serum starved cells irrespective of p38 MAPK inhibition. Collectively, our findings suggest that p38 MAPK exerts a negative effect on VEGF-mediated signaling through VEGFR2 in serum starved neuroblastoma cells. Furthermore, VEGF signals protection against a caspase-mediated cell death that is regulated by p38 MAPK-dependent and -independent mechanisms.     

Inhibition of the p38 mitogen-activated protein kinase (MAPK) pathway attenuates cerebral vasospasm following experimental subarachnoid hemorrhage in rabbits

The p38 mitogen-activated protein kinase (MAPK) plays an important role in apoptosis and is also involved in the development of cerebral vasospasm after subarachnoid hemorrhage (SAH). Here, we sought to examine whether inhibition of p38 MAPK could attenuate cerebral vasospasm and investigate the underlying mechanisms in a rabbit SAH model. SAH was established in rabbits (n=12/group) using the double-hemorrhage method. We observed apparent vasospasm in the basilar arteries of rabbits with SAH, which was significantly attenuated by SB203580, a selective p38MAPK inhibitor. Immunoblotting assays showed enhanced phosphorylation of p38 MAPK and ATF2 and increased caspase-3 cleavage following SAH, which were, however, markedly suppressed by SB203580. TUNEL staining further revealed significant apoptosis in the basilar arteries of rabbits with SAH, which was scantly present in rabbits treated with SB203580. Our results demonstrated that p38 MAPK was activated in cerebral vasospasm and associated with increased apoptosis in the basilar arteries and p38 MAPK inhibition suppressed apoptosis, suggesting that p38 MAPK could be a novel therapeutic target for cerebral vasospasm.     

TNF-α对人脐静脉内皮细胞活性及PD-L1蛋白表达的影响

目的研究外源性肿瘤坏死因子α（TNF-α）对原代人脐静脉内皮细胞（HUVECs）活性及程序性死亡因子配体PD-L1蛋白表达的影响,探讨动脉粥样硬化的免疫机制。方法体外培养HUVECs,加入不同浓度TNF-α持续刺激48h,CCK-8法检测450nm波长处吸光度值（OD值）,计算细胞生长存活率。选同代细胞重复培养并干预,Westernblot方法检测细胞PD-L1蛋白表达。使用SB203580阻断p38MAPK通路后再用TNF-α干预HUVECs,比较各组细胞PD-L1蛋白表达。结果实验组HUVECs在450nm波长处的吸光度值较空白对照组明显降低（P〈0.05）,细胞存活率依次下降。实验组细胞PD-L1蛋白表达随TNF-α浓度增高逐渐降低（P〈0.05）。TNF-α单独刺激组PD-L1蛋白表达较TNF-α与SB203580共刺激组明显降低（P〈0.05）,SB203580阻断效应明显。结论 TNF-α可明显抑制HUVECs细胞活性,并降低PD-L1蛋白表达,p38MAPK通路可能参与了这一过程。