耐碳青霉烯类革兰氏阴性菌外膜囊泡(OMVs)的研究进展

Progress in Research on Outer Membrane Vesicles (OMVs) of Carbapenem-Resistant Gram-Negative Bacteria

摘要: 耐碳青霉烯类革兰氏阴性菌(CRGNB)由于其多重耐药性和高致病力，已成为全球公共卫生的严峻挑战。近年来研究发现，革兰氏阴性菌在生长过程中分泌的纳米级双层脂质结构——外膜囊泡(OMVs)，在CRGNB的生存、耐药性种群扩散和宿主互作中发挥着关键的动态媒介作用。本文综述了CRGNB来源外膜囊泡(CRGNB-OMVs)的最新研究进展。首先，阐述了OMVs与CRGNB耐药机制的紧密关联，包括包裹耐药质粒以介导非接触式的耐药基因水平转移，富集碳青霉烯酶发挥胞外“诱饵”与直接水解作用，以及在抗菌药物压力下动态重组外膜孔道蛋白(如OmpK36、OprD、OmpA等)以强化细菌屏障。其次，重点针对主要CRGNB (CRKP、CRAB、CRPA)的独特性进行了横向比对，详细论述了其在特定生物组分、病理生理功能和临床相关性上的异同。随后，探讨了OMVs在致病性中的多重作用，其不仅高度富集并跨膜递送毒力因子，还通过激活宿主TLR4/TLR2通路及胞质内NLRP3炎症小体，引发巨噬细胞焦亡与线粒体损伤，诱发全身性炎症反应综合征(SIRS)并具备跨越血脑屏障的能力，同时协助细菌实现补体消耗与免疫逃逸。最后，总结了基于CRGNB-OMVs的临床应用探索，包括将其改造为生物工程化纳米疫苗载体、早期感染特异性生物标志物、器官靶向药物递送系统及肿瘤免疫治疗调节剂，并指出了其在标准化规模化生产及毒性控制上面临的挑战。未来的研究应加速推动CRGNB-OMVs从基础机制向临床精准诊疗的转化，为应对日益严峻的碳青霉烯耐药危机提供全新的生物医学策略。

Abstract: Carbapenem-resistant Gram-negative bacteria (CRGNB) pose a severe threat to global public health due to their multidrug resistance and high pathogenicity. Recent studies have revealed that outer membrane vesicles (OMVs)—nanosized bilayer lipid structures secreted by Gram-negative bacteria during growth—play a critical role as dynamic mediators in bacterial survival, resistance dissemination, and host-pathogen interactions. This paper systematically reviews the latest research progress on CRGNB-derived OMVs (CRGNB-OMVs). First, we elucidate the close association between OMVs and CRGNB resistance mechanisms, including the encapsulation of resistance plasmids to mediate non-contact horizontal gene transfer, the enrichment of carbapenemases acting as extracellular “decoys” and directly hydrolyzing antibiotics, and the dynamic remodeling of outer membrane porins/proteins (such as OmpK36, OprD, and OmpA) under antibiotic pressure to strengthen the bacterial barrier. Second, a horizontal comparison was conducted focusing on the unique characteristics of the main CRGNB (CRKP, CRAB, and CRPA). Their similarities and differences in terms of specific biological components, pathophysiological functions, and clinical relevance were discussed in detail. Third, we discuss the multifaceted roles of OMVs in pathogenesis, highlighting how they highly enrich and intracellularly deliver virulence factors, trigger macrophage pyroptosis and mitochondrial damage via the activation of host TLR4/TLR2 pathways and cytoplasmic NLRP3 inflammasomes, induce systemic inflammatory response syndrome (SIRS), exhibit the capacity to cross the blood-brain barrier, and facilitate bacterial immune evasion through complement consumption. Finally, we summarize the exploration of CRGNB-OMV-based clinical applications, such as their modification into bioengineered nanovaccine vectors, early infection-specific biomarkers, organ-targeted drug delivery systems, and cancer immunotherapy regulators, while pointing out current challenges in standardized large-scale production and toxicity mitigation. Shifting the research focus of CRGNB-OMVs from basic mechanisms to clinical precision translation will offer novel biomedical strategies to combat the escalating carbapenem resistance crisis.