阳离子抗菌肽LL-37及其在脓毒症防治中的研究进展

Cationic antimicrobial peptide LL-37 and it＇ s potential therapeutic role in sepsis

阳离子抗菌肽包括防御素和cathelicidin两大类家族。hCAP-18／LL-37是迄今发现的存在于人体中唯一的cathelicidin家族成员，基因定位于3p21．3，主要表达于单核细胞、上皮细胞。LL-37是其具有杀菌活性的成分，由37个氨基酸残基组成，具有两亲性α-螺旋结构。体外研究显示，LL-37具有抗菌、中和内毒素、化学趋化、促进血管新生、组织修复等作用。在体研究发现，LL-37不仅能杀灭致病菌，还能抑制由细菌内、外毒素或细胞壁成分诱发的炎症介质的产生和释放，在脓毒症的发生、发展与防治中有着重要作用。

Cationic antimicrobial peptides include two major families： defensins and cathelicidins, hCAP-18/LL-37 is the only member of cathelicidins found in human, which is mainly expressed in monocytes and epithelia. The gene coding for hCAP-18/LL-37 is located at 3p21.3. LL-37, the biological active component of hCAP-18, is composed of 37 amino acids and has an amphipathic α- helical conformation. In vitro experiments have demonstrated that LL-37 has antibacterial, endotoxin-neutralizing, chemoattracting and angiogenesis effects. In vivo experiments have revealed that LL-37 is able to kill bacteria and suppress the release of inflammatory factors induced by bacterial components. LL-37 may play an important role in initiation, development and prevention of sepsis.