新疆天山,阿尔泰山山地森林脑炎自然疫源地考察报告

1964～1966年我们考察了位于新疆天山山脉的15个县的林区及阿尔泰山山脉的3个县的林区,发现全沟硬蜱(Ixodes persulcatus)分布于海拔1500～1800m的森林草原景观中。并从天格尔山北坡的乌鲁木齐(N43°33′,E87°07′)、昌吉县林区(N43°30′,E86°55′),依连哈比尔尕山北坡的玛纳斯(N43°53′,E86°06′)、沙湾县林区(N43°56′,E85°12′),婆罗克努山南坡的尼勒克县林区(N44°02′,E82°38′),科古琴山南坡的霍城县林区(N44°28′,E81°10′),那拉提山北坡的新源(N43°16′,E84°01′)、巩留县林区(N43°11′,E82°44′)和哈尔克山北坡的特克斯(N43°59′,E81°55′)、昭苏县林区(N42°48′,E80°35′)采集的全沟硬蜱分离出森林脑炎病毒(Tick-borne encephalitis flavivirus)。从而判定上述地区存在森林脑炎自然疫源地。全沟硬蜱为主要媒介,其带毒率介于14.3％～47.7％。狍(Capreolus capreolus)、狐(Vulpes vulpes)、灰旱獭(Marmotabaibacina)、牛、马和羊均可作为该蜱的天然饲养者,从它们的血清中均检出森林脑炎病毒中和抗体。在疫源地内有散发病例发生。查布察尔(N43°34′,E81°08′、哈巴河(N48°28′,E86°42′)、奇台(N43°38′,E89°42′)、吉木萨尔(N43°49′,E89°)因采集材料过少尚不能确定     

The paradox of the binomial Ixodes ricinus activity and the observed unimodal Lyme borreliosis season in Hungary

The change of ambient temperature plays a key role in determining the run of the annual Lyme season. Our aim was to explain the apparent contradiction between the annual unimodal Lyme borreliosis incidence and the bimodal Ixodes ricinus tick activity run – both observed in Hungary – by distinguishing the temperature-dependent seasonal human and tick activity, the temperature-independent factors, and the multiplicative effect of human outdoor activity in summer holiday, using data from Hungary in the period of 1998–2012. This separation was verified by modeling the Lyme incidence based on the separated factors, and comparing the run of the observed and modeled incidence. We demonstrated the bimodality of tick season by using the originally unimodal Lyme incidence data. To model the outdoor human activity, the amount of camping guest nights was used, which showed an irregular run from mid-June to September. The human outdoor activity showed a similar exponential correlation with ambient temperature to that what the relative incidence did. It was proved that summer holiday has great influence on Lyme incidence.     

蜱抗原免疫接种诱导宿主抵抗力的研究

本文选用中华硬蜱雌性成虫中肠抗原、卵抗原对家免进行人工免疫接种，在按常规方法免疫接种三次后，用中华硬蟀成虫进行感染（叮咬），分别观察中肠抗原接种组、卵抗原接种组、佐剂对照组和空白对照组中华硬蜱的吸血量、生殖情况。结果显示．中华硬蜱叮咬中肠抗原免疫接种兔后其吸血量、产卵量均较对照组显著降低，蜱的吸血量较佐剂和空白对照组分别下降48．56％和54．65％，产卵量下降52.8％和57.9％，而中华硬蜱叮咬卵抗原免疫接种组兔后其吸血、生殖能力较对照组无显著性差异（P＜0．05）。实验表明中华硬碑中肠抗原可有效诱导宿主产生特异性抵抗力，并对该现象进行了分析讨论。     

叮咬不同免疫力兔后中华硬蜱中肠上皮细胞超微结构的观察

目的　探讨叮咬不同免疫力兔后中华硬蜱中肠上皮细胞的病理变化。　方法　选用中华硬蜱相对分子质量 (Mr)为 10 5 0 0 0纯化抗原 ,按常规方法分别于后足掌、腹股沟以及颈背部多点皮内注射免疫新西兰兔。免疫后每只兔用 3 0只雌性中华硬蜱成虫叮咬 ,于 2 4h、48h、72h、5d及 8d ,每组各取 3只吸血中华硬蜱观察其中肠上皮细胞超微结构的变化。　结果　中华硬蜱初次叮咬兔后 ,消化细胞随叮咬时间延长而增多增大 ,微绒毛较密集 ,排列整齐 ,胞质内细胞器丰富 ,各单位膜结构清晰 ,并出现顶端小管、小泡、大量脂滴和高铁血红蛋白颗粒 ;近基膜的细胞膜内褶形成发达的基底迷路系统。叮咬经Mr 10 5 0 0 0纯化抗原免疫接种兔后 ,中华硬蜱中肠上皮细胞严重损伤和破坏 ,消化细胞数量与体积较初次叮咬组及佐剂对照组间差异具有显著性意义。叮咬后 2 4～ 48h消化细胞表面微绒毛减少 ,变短、排列不整 ,细胞粗面内质网扩张 ,线粒体嵴减少 ,高铁血红蛋白颗粒及脂滴等均较初次叮咬组和佐剂对照组明显减少 ,基底迷路系统空泡化 ,基膜变性、松散和断裂等。叮咬后 72h～ 8d ,细胞器变性、坏死 ,细胞核固缩、碎裂以及细胞溶解、碎裂等。　结论　中华硬蜱叮咬Mr 10 5 0 0 0的纯化抗原免疫接种新西兰兔 ,能使其产生获得性免疫力。     

中华硬蜱叮刺宿主后免疫相互作用的研究

在实验室条件控制下,中华硬蜱重复叮咬家兔后吸血量明显减少,初次叮咬后吸血增重233.78±44.71mg,第二和第三次叮咬分别下降至67.03±25.18mg和80.23±29.96mg(P<0.001)。被咬后的家兔血清经ELISA测定其体内蜱抗体(OD值0.48)较对照组家兔(OD值0.08)显著高(P<0.01)。免疫后家兔其~3H-TdR淋巴细胞转化试验和皮肤试验与对照组家兔有显著差异,表明家兔对中华硬蜱叮咬所产生的获得住免疫力,包括宿主的体液免疫和细胞免疫。     

Tick saliva increases production of three chemokines including monocyte chemoattractant protein‐1, a histamine‐releasing cytokine

The effect of Ixodes ricinus tick saliva on the production of various cytokines and chemokines by mouse splenocytes was tested by a cytokine array. We demonstrated a strong upregulation of three chemokines, monocyte chemoattractant protein‐1 (MCP‐1), thymus‐derived chemotactic agent 3 (TCA‐3) and macrophage inflammatory protein 2 (MIP‐2). MCP‐1 could be induced by tick saliva itself. While TCA‐3 and MIP‐2 are engaged in Th2 polarization of the host immune response associated with tick feeding, MCP‐1 may act as a histamine release factor, increasing blood flow into the feeding lesion thus facilitating tick engorgement in the late, rapid feeding phase.     

Effect of tick saliva on immune interactions between Borrelia afzelii and murine dendritic cells

Interaction between mouse dendritic cells (DCs) and Borrelia afzelii spirochetes was monitored on three different levels: phagocytosis of spirochetes by DCs, production of cytokines by Borrelia-stimulated DCs and the ability of Borrelia-exposed DCs to activate specific CD4+ T lymphocytes. The effect of Ixodes ricinus tick saliva on each of these interactions was examined. Tick saliva was shown to decrease the number of phagocytosing DCs. The ability of Borrelia-exposed DCs to induce both proliferation and IL-2 production by specific CD4+ T cells was significantly reduced by tick saliva. And surprisingly, we have shown an inhibitory effect of tick saliva on the production of both Th1 (TNF-α and IL-6) and Th2 (IL-10) cytokines by DCs. Our data reveal a complex inhibitory effect of tick saliva on Borrelia-DCs interaction.     

Blood donor Borrelia burgdorferi sensu lato seroprevalence and history of tick bites at a northern limit of the vector distribution

In order to study the antibody seroprevalence of the causal agent of Lyme borreliosis, Borrelia burgdorferi sensu lato (s.l.), and the history of tick bites at a geographical distribution limit of Ixodes ricinus, we compared healthy blood donors in geographically extreme regions: the borreliosis‐endemic Vestfold County (59°N) and the region of northern Norway. Blood samples were screened using IgG/VlsE ELISA, and positive/borderline samples were confirmed using C6 ELISA and immunoblot assays. Also, donors completed a questionnaire consisting of several items including the places they have lived, and whether they owned any pets. The seroprevalence was 0.48% (5/1048) in northern Norway and 9.25% (48/519) in Vestfold County. Seven donors (of 1048) had experienced a single tick bite in the southern part of Nordland County (65°N) in northern Norway. This first study on B. burgdorferi s.l. antibody seroprevalence and tick bites on humans and pets in northern Norway showed that the seroprevalence of B. burgdorferi s.l. infection and the risk of tick bite in northern Norway are insignificant; the fact that only five positive IgG samples were detected underscores the very low background seroprevalence. These results suggest that so far I. ricinus has not expanded north of the previously established geographical distribution limit.     

环境因子对我国卵形硬蜱适生区分布的影响研究

［摘要］　目的　探索影响卵形硬蜱适生区分布的环境因子及未来环境变化对卵形硬蜱适生区分布的影响。方法　通过文献检索获取我国已知卵形硬蜱分布点数据,结合环境因子数据,运用最大熵模型对卵形硬蜱适生区分布进行模拟,并根据2050、2070年环境数据对卵形硬蜱适生区分布变化进行预测。结果　目前我国卵形硬蜱适生区面积为311.0万km2,占国土面积的32.28%,主要集中在西南、西北地区;在筛选出的16个环境因子中,温度季节性变化标准差、年均降水量、海拔为影响卵形硬蜱适生区分布的主导环境因子,累计贡献率为76.5%;2050、2070年我国卵形硬蜱适生区分布呈向西北、东北扩大趋势,且高适生区占比增加。结论　温和的气候、充足的降水及较高的海拔适宜卵形硬蜱生存,未来气候改变可能引起我国卵形硬蜱适生区分布范围扩大。