Atherosclerosis Peripheral Nervous System Crosstalk in Apolipoprotein E-deficient and Human Apolipoprotein E Isoform-specific Knock-in Mice

已知外周炎症可被周围神经系统(PNS)感知和影响。动脉粥样硬化是一种未消退的动脉炎症性疾病。然而，到目前为止，研究动脉粥样硬化与PNS之间的关系尚不合理，因为动脉内膜，即动脉粥样硬化病变发生的部位，没有受到神经支配。我们小组的特点是APOE-/-小鼠的主动脉外膜中有动脉第三淋巴器官(ATLO)。由于所有动脉的外膜都受到神经支配，ATLOS的发现增加了ATLO可能与PNS相互作用、被感觉到并受其影响的可能性。我们推测，对病变主动脉中三叉神经节的研究可能揭示动脉粥样硬化与三叉神经节之间的相互作用。我在过去4年中获得的未发表的数据确实揭示了病变的外膜节段和PNS之间全面的神经免疫相互作用。我观察到：1)动脉粥样硬化斑块附近的外膜节段神经轴突密度明显增加，主动脉旁神经节(PAG)和背根神经节(DRGs)有炎性浸润；II)轴突直接与免疫细胞相互作用；III)PAG和神经附近出现TLO样结构。为了了解动脉粥样硬化-PNS串扰的主要机制，我在以下详细的研究项目中提出了以下建议：研究TLO和外周神经节的炎性浸润物(AIM1)的形态和结构；利用人源化APOE3基因敲入(Ki)和ApoE4Ki小鼠(AIM2)确定高脂血症和ApoE亚型对神经免疫串扰的作用；确定哪些PNS成分参与神经免疫串扰(Aim3)；通过PAG mRNA微阵列构建转录图谱(Aim4)；分析WT和APOE-/-小鼠(Aim5)的神经递质受体；检测PNS相关的TLO(Aim6)。

Peripheral inflammation is known to be sensed and affected by the peripheral nervous system (PNS). Atherosclerosis is a nonresolving inflammatory disease of arteries. However, there was no rational - until now - for studying the relation between atherosclerosis and the PNS, because the intima of arteries, i.e. the location where atherosclerosis pathology develops, is not innervated. Our group characterized artery tertiary lymphoid organs (ATLOs) in the aorta adventitia of Apoe-/- mice. Since the adventitia of all arteries is innervated, the discovery of ATLOs raised the possibility that ATLOs might interact with, be sensed, and affected by the PNS. We reasoned that studies into the PNS in the diseased aorta might possibly uncover atherosclerosis-PNS interactions. Unpublished data that I obtained over the past 4 years indeed reveal comprehensive neuroimmune interactions between diseased adventitia segments and the PNS. I observed: i) that adventitia segments adjacent to atherosclerotic plaques show markedly increased nerve axon density and that paraaortic ganglia (PAGs) and dorsal root ganglia (DRGs) show inflammatory infiltrates; ii) that axons directly interact with immune cells; and iii) that TLO-like structures emerge near PAGs and nerves. To understand the principal mechanisms of atherosclerosis-PNS crosstalk I propose in the research project detailed below to study the morphology and structure of TLOs and the inflammatory infiltrates in peripheral ganglia (Aim1); define roles of hyperlipidemia and of ApoE isoforms on neuroimmune crosstalks using humanized Apoe3 knock-in (KI) and Apoe4 KI mice (Aim2); determine which PNS constituents are involved in neuroimmune crosstalk (Aim3); construct transcript atlases through mapping of PAG mRNA microarrays (Aim4); analyze neurotransmitter receptors in Wt and Apoe-/- mice (Aim5); examine PNS-associated TLOs in human coronary artery adventitiae (Aim6).