机体识别病毒核酸的几种分子模式及途径

近些年机体病原相关模式受体及其识别分子机制的研究,极大地促进了先天性分子免疫学的发展,并成为现代免疫学研究的重点和热点领域。作者通过机体识别病毒核酸的Toll样受体(Toll-like receptors,TLRs)、RIG-I样受体(RIG-I like receptors,RLRs)、NOD样受体(NOD-like receptors,NLRs)和DAI(DNA-dependent activatorof interferon-regulatory factors,DAI)等模式识别分子的细胞定位、分子结构及其识别病毒核酸途径的介绍,系统、全面地探讨了宿主机体如何全方位识别和消除入侵病毒的分子免疫防御途径,为抗病毒药物和疫苗的设计以及抗病育种提供了理论依据。     

传染性支气管炎病毒感染对蛋雏鸡输卵管雌激素受体及孕激素受体表达的影响

以不同传染性支气管炎病毒（肾型IBV-河北分离株与呼吸型IBV-M41）分别感染蛋雏鸡,通过测定输卵管蛋白分泌部及子宫雌激素受体（Estrogen receptor,ER）和孕激素受体（Progesterone receptor,PR）的表达水平,来探讨IBV早期感染（10d）对抑制蛋鸡输卵管发育的作用机制。结果显示,IBV感染降低子宫和蛋白分泌部ER mR-NA、PR mRNA的表达水平,即致子宫ER mRNA和PR mRNA的表达低于检测水平;蛋白分泌部ER mRNA和PR mRNA的表达水平显著降低（P〈0.01）,且M41的作用幅度较肾型IBV更为显著（P〈0.01）。结果表明,IBV可通过降低ER和PR的表达水平,抑制输卵管对雌激素的应答能力而影响输卵管的发育。     

Expression patterns of influenza virus receptors in the respiratory tracts of four species of poultry

The primary determinant of influenza virus infectivity is the type of linkage between sialic acid and oligosaccharides on the host cells. Hemagglutinin of avian influenza viruses preferentially binds to sialic acids linked to galactose by an α-2,3 linkage whereas hemagglutinin of human influenza viruses binds to sialic acids with an α-2,6 linkage. The distribution patterns of influenza receptors in the avian respiratory tracts are of particular interest because these are important for initial viral attachment, replication, and transmission to other species. In this study, we examined the distribution patterns of influenza receptors in the respiratory tract of chickens, ducks, pheasants, and quails because these species have been known to act as intermediate hosts in interspecies transmission. Lectin histochemistry was performed to detect receptor-bearing cells. Cell-specific distribution of the receptors was determined and expression densities were compared. We observed species-, site-, and cell-specific variations in receptor expression. In general, receptor expression was the highest in quails and lowest in ducks. Pheasants and quails had abundant expression of both types of receptors throughout the respiratory tract. These results indicate that pheasants and quails may play important roles as intermediate hosts for the generation of influenza viruses with pandemic potential.     

鸡红细胞免疫功能研究 I.鸡红细胞C_(3b)受体测定

建立了用C_(3b)致敏酵母检测鸡红细胞C_(3b)受体的E—C_(3b)R花环试验,以及用C_(3b)未致敏酵母检测鸡红细胞表面免疫复合物的E—IC花环试验.经检测,Avian(45例)、AA(282例)、罗丝(141例)和星杂579(58例)4个品种鸡的E—C_(3b)R花环率/E—IC花环率分别为19.4±4.4%/5.2±3.2%,15.4±3.1%/3.2±2.8%,9.7±3.2%/4.6±2.0%和9.4±2.3%/3.9±1.5%.本实验结果表明,鸡红细胞上存在C_(3b)受体,该受体对不同动物来源的补体有不同的亲和性,其免疫粘附具有较强的pH值依赖性.     

豌豆蚜特异性扩张分支气味受体基因的克隆及表达分析

豌豆蚜Acyrthosiphon pisum气味受体家族存在明显扩张现象,推测在豌豆蚜寄主适应过程中起着重要作用。本研究旨在克隆豌豆蚜特异性扩张分支上的气味受体基因,明确这些气味受体基因在不同组织中的表达水平。通过PCR技术克隆特异性扩张分支上气味受体基因的全长序列,采用实时荧光定量RT-qPCR技术测定这些基因在触角及足中的表达水平。克隆获得豌豆蚜特异性扩张分支中4个气味受体基因全长序列(GenBank登录号：OL739156-OL739159),分别编码374～376个氨基酸,序列相似性较高,为68.09%～83.11%,均具有7个跨膜结构域。荧光定量RT-qPCR结果显示ApisOR6、ApisOR8、ApisOR13和ApisOR14基因在豌豆蚜成虫触角及足中均有表达,其中ApisOR8、ApisOR13和ApisOR14基因在触角中偏好表达,ApisOR13基因在触角中的表达量最高。本研究为解析豌豆蚜特异性扩张气味受体的功能提供了分子基础。     

狭胸天牛成虫下颚须和下唇须化感器研究

狭胸天牛Ｐｈｉｂｌｕｓａｎｔｅｎｎａｔｕａ（Ｇｙｌｌ．）成虫下颚须具有约１２０个栓锥感受器，分为３种类型。下唇须具有约１００个栓锥感受器，分为两种类型。下颚须和下唇须都有探测寄主植物、配偶和产卵场所的作用。     

Design of new α-conotoxins: from computer modeling to synthesis of potent cholinergic compounds

A series of 14 new analogs of α-conotoxin PnIA Conus pennaceus was synthesized and tested for binding to the human α7 nicotinic acetylcholine receptor (nAChR) and acetylcholine-binding proteins (AChBP) Lymnaea stagnalis and Aplysia californica. Based on computer modeling and the X-ray structure of the A. californica AChBP complex with the PnIA[A10L, D14K] analog, single and multiple amino acid substitutions were introduced in α-conotoxin PnIA aimed at compounds of higher affinity and selectivity. Three analogs, PnIA[L5H], PnIA[A10L, D14K] and PnIA[L5R, A10L, D14R], have high affinities for AChBPs or α7 nAChR, as found in competition with radioiodinated α-bungarotoxin. That is why we prepared radioiodinated derivatives of these α-conotoxins, demonstrated their specific binding and found that among the tested synthetic analogs, most had almost 10-fold higher affinity in competition with radioactive α-conotoxins as compared to competition with radioactive α-bungarotoxin. Thus, radioiodinated α-conotoxins are a more sensitive tool for checking the activity of novel α-conotoxins and other compounds quickly dissociating from the receptor complexes.