犬埃立克体病原特点及其致病性研究进展

doi:10.16431/j.cnki.1671-7236.2023.05.029

摘要/Abstract

摘要： 犬埃立克体(Ehrlichia canis,E.canis)引起的传染性疾病对犬或人类生命健康具有严重威胁,其可通过皮肤表面的伤口或节肢动物的叮咬侵入机体,进一步引起机体一系列反应,导致犬埃立克体相关疾病。此外,由犬埃立克体引起的疾病的临床症状与较多疾病的临床症状相似,在快速诊断上带来了一定程度的困难。犬埃立克体为严格的胞内寄生病原体,革兰氏染色为阴性,吉姆萨染色为紫色。目前已能成功分离该病原,并实现体外传代培养。犬埃立克体可诱导宿主细胞自噬,夺取宿主细胞的营养物质利于自身存活和增殖,并可诱导机体发生免疫反应,产生大量致炎因子,引起机体发热和对组织器官造成不同程度的损伤。犬埃立克体存在一种特殊的免疫逃避机制,能避免被宿主溶酶体或其他免疫因子清除,并在巨噬细胞内生长繁殖,破坏宿主细胞内的抗炎因子,进而破坏宿主的免疫功能。然而,犬埃立克体夺取或破坏宿主细胞营养成分或存活的具体机制尚不清楚,且如何逃避宿主免疫系统"追踪"有待研究。治疗方面,犬埃立克体仅对多西环素(doxycycline)等部分抗生素敏感,预防该病的最佳方法仍是定期清除体外寄生虫。笔者对犬埃立克体的病原特性、流行病学、致病机制等主要方面及部分病原与宿主细胞间作用的研究现状进行了综述。

关键词: 犬; 犬埃立克体; 单核-巨噬细胞; 致病机制

Abstract: Infectious diseases caused by Ehrlichia canis (E.canis) have a serious threat to the health of dogs or human.E.canis can invade the body through wounds on the skin surface or bites of arthropods,triggering a series of reactions in the body and leading to E.canis-related diseases.In addition,the clinical symptoms of diseases caused by E.canis are similar to other diseases,which brings difficulties in ways of rapid diagnosis.E.canis is a strict intracellular parasitic pathogen,and is negative stained by Gram staining and is purple stained by Gimsa staining.It is possible to isolate this pathogen successfully and realize culture in vitro.E.canis is able to induce autophagy of host cells,remaining their own survival and proliferation through capturing nutrients from the host,and can induce the body to have an immune responses.Through producing a large number of inflammatory factors,E.canis causes fever and brings damage to tissues and organs.E.canis has a special mechanism of immune escape to avoid being eliminated by lysosomes or other immune factors of hosts.E.canis can grow and reproduce in macrophages and destroy the anti-inflammatory factors in the host cell in order to destroy the host immune function.However,how E.canis capturing or destroying nutrients and survival of hosts remains unclear,and evading the 'tracking’ of immune system of hosts are still further investigated.In terms of treatment,E.canis related diseases are only sensitive to some antibiotics such as doxycycline.However,the best way to prevent this disease is to remove regularly ectoparasite.Consequently,the aim of the article is to summarize the pathogenesis,epidemiology and pathogenic mechanism of E.canis,including advanced research status between partial pathogens and host cells.

Key words: canis; Ehrlichia canis; monocyte-macrophage; pathogenic mechanism

中图分类号:

S852.64

张婧怡, 陈莉, 黄思扬, 陈祥, 刘宗平, 仝锡帅. 犬埃立克体病原特点及其致病性研究进展[J]. 中国畜牧兽医, 2023, 50(5): 2023-2031.

ZHANG Jingyi, CHEN Li, HUANG Siyang, CHEN Xiang, LIU Zongping, TONG Xishuai. Research Progress on Pathogenic Characteristics and Pathogenicity of Ehrlichia canis[J]. China Animal Husbandry and Veterinary Medicine, 2023, 50(5): 2023-2031.

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