Inflammation-Induced Pericyte Dysfunction Is Abrogated by Interfering with the CXCL12/CXCR4 Signaling Pathway
Inflammation-Induced Pericyte Dysfunction Is Abrogated by Interfering with the CXCL12/CXCR4 Signaling Pathway
复制标题
通过干扰 CXCL12/CXCR4 信号通路消除炎症引起的周细胞功能障碍
DOI：
10.1164/ajrccm-conference.2021.203.1_meetingabstracts.a4490
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发表时间：
2021
期刊：
影响因子：
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通讯作者：
Johnson J
中科院分区：
文献类型：
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作者：
Johnson J
背景微血管通透性升高和炎症细胞渗入气道腔是过敏性哮喘气道炎症反应的特征。血管壁由内皮细胞和周细胞组成；尽管白细胞通过内皮细胞的迁移相对较快，但这些细胞需要相当长的时间通过周细胞才能突破血管壁。针对周细胞来减轻血管通透性失调的研究有限。我们已经证明，当暴露于空气过敏原屋尘螨 (HDM) 5 周后，周细胞会与气道微脉管系统解耦，以应对呼吸系统的挑战。进一步研究表明，HDM 诱导的过敏性气道疾病的特点是 CXCL12 水平升高和血管周细胞覆盖率降低。抑制 CXCL12 活性的中和配体 (LIT-927) 可以逆转周细胞与气道脉管系统的解偶联。方法在有和没有 TNF-α 预处理的情况下培养人类周细胞，并进行 Transwell 迁移测定和单核细胞迁移测定。使用中和配体 LIT-927 以及 ERK、PI3/AKT 和 p38 MAPK 信号通路抑制剂（分别为 ARRY、LY294002 和 SB203580）研究了周细胞对 CXCL12 反应的抑制。 TNF-α 预处理后，向 CXCL12 和 FCS 的迁移显着增加 (p<0.001)。 ARRY、LY294002、SB203580 存在时，CXCL12 诱导的周细胞迁移受到显着抑制 (p< 0.05)，表明这些途径通过 CXCL12/CXCR4 信号轴在周细胞迁移中发挥重要作用。有趣的是，当周细胞在缺乏 CXCL12 的情况下暴露于 MAPK 抑制剂时，迁移也显着减少（p < 0.05），这表明抑制 MAPK 通路很难在不产生明显不良副作用的情况下局部实现，从而使其成为一个没有吸引力的治疗靶点。然而，我们能够使用 LIT-927 局部中和 CXCL12，在体外抑制 CXCL12/CXCR4 通路。 LIT-927 治疗能够显着逆转 CXCL12 诱导的未治疗周细胞 (p < 0.01) 和 TNF-α 预处理周细胞 (p < 0.05) 的迁移增加。通过CXCL12中和和MAPK通路抑制来抑制CXCR4信号也显着抑制了单核细胞通过周细胞单层的迁移(P<0.01)。结论LIT9-27能够将CXCL12诱导的周细胞迁移单核细胞迁移逆转回对照水平。值得注意的是，LIT-927 在抑制 CXCL12 诱导的周细胞迁移方面似乎与 MAPK 抑制剂等效，表明 LIT927 在治疗炎症诱导的血管功能障碍方面是 MAPK 抑制剂的有效治疗替代品。
BackgroundElevated microvascular permeability and the exudation of inflammatory cells into the airway lumen is a characteristic feature of the airway inflammatory response in allergic asthma. The vascular wall is composed of endothelial cells and pericytes; although leukocyte transmigration through endothelial cells is relatively rapid, these cells require considerable transit time through pericytes in order to breach the vascular wall. There have been limited studies targeting pericytes to attenuate dysregulated vascular permeability. We have shown that pericytes uncouple from the airway microvasculature in response to respiratory challenge to the aeroallergen house dust mite (HDM) exposure for a period of 5 weeks. Further investigations showed that HDM-induced allergic airway disease is characterized by elevated levels of CXCL12 and decreased vascular pericyte coverage. Pericyte uncoupling from the airway vasculature was reversed in response to a neutralizing ligand that suppresses CXCL12 activity (LIT-927).MethodsHuman pericytes were cultured with and without TNF-α pretreatment and subjected to Transwell migration assays and monocyte transmigration assays. Suppression of pericyte responses to CXCL12 was investigated using the neutraligand LIT-927 and inhibitors of the ERK, PI3/AKT, and p38 MAPK signalling pathways (ARRY, LY294002, and SB203580, respectively).ResultsIn the Transwell assay, pericytes migrated to a similar degree towards CXCL12 and fetal calf serum (as the positive control); migration toward CXCL12 and FCS was significantly (p< 0.001) increased following TNF-α pretreatment. CXCL12-induced pericyte migration was significantly inhibited (p< 0.05) in the presence ARRY, LY294002, SB203580, indicating that these pathways play a significant role in pericyte migration via the CXCL12/CXCR4 signalling axis. Interestingly, there was also a significant reduction in migration when pericytes were exposed to MAPK inhibitors in the absence of CXCL12 (p< 0.05), suggesting that inhibiting MAPK pathways is difficult to achieve locally without significant unwanted side effects, making this an unattractive therapeutic target. However, we were able inhibit the CXCL12/CXCR4 pathway in vitro using LIT-927 to locally neutralize CXCL12. LIT-927 treatment was able to significantly reverse the CXCL12-induced increase in migration on both untreated (p< 0.01) and TNF-α pretreated pericytes (p< 0.05). Suppression of CXCR4 signalling via CXCL12 neutralization and MAPK pathway inhibition also significantly suppressed monocyte transmigration through a pericyte monolayer (P< 0.01).ConclusionsLIT9-27 is able to reverse CXCL12-induced pericyte migration monocyte transmigration back to control levels. Notably, LIT-927 appeared to be equipotent to MAPK inhibitors in the suppression of CXCL12-induced pericyte migration, indicating that LIT927 is an effective therapeutic alternative to MAPK inhibitors in the treatment of inflammation-induced vascular dysfunction.