表达传染性喉气管炎病毒gB基因和新城疫病毒F基因重组病毒免疫及强毒攻击后外周血T淋巴细胞亚群的动态

采用流式细胞检测技术对表达传染性喉气管炎病毒gB基因和新城疫病毒F基因重组鸡痘病毒（rFPV-gB-F）、新城瘦弱毒疫苗以及传染性喉气管炎弱毒疫苗免疫和传染性喉气管炎以及新城疫强毒攻击后外周血T细胞表型亚类（CD4^＋、CD8^＋、XCRγδ^＋）的变化动态进行监测。重组疫苗和禽痘疫苗免疫之后，CD8^＋和TCRγδ^＋的细胞数先升高后回落；在NDV强毒攻击之后，ND疫苗免疫组的TCRγδ^＋数量升高，rFPV-gB-F免疫组的三种细胞数量在第l周都下降，随后升高；ILT疫苗在免疫后的第1周，CD4^＋细胞数量下降。结果提示rFPV-gB-F可以诱发相应的细胞免疫应答，但是有关传染性喉气管炎病毒导致的细胞免疫需要进一步的研究，     

鸡IFN-γ重组鸡痘病毒对鸡传染性腔上囊炎MB43弱毒疫苗免疫鸡免疫应答的影响

将重组鸡痘病毒（rFPV—IFN-γ）与IBDMB43弱毒疫苗联合接种SPF鸡，研究重组鸡IFN-γ对IBD疫苗免疫效果的影响。结果显示，rFPV—IFN-γ和MB43弱毒疫苗联合免疫组（MB43＋rFPV-IFN-）＂）及rlFN-γ和MB43弱毒疫苗联合免疫组（MB43＋rIFN-γ）在免疫后第2周即可检出ELISA抗体，比MB43疫苗单独免疫组早1周。用IBDVGx株攻击后，MB43＋rFPV-IFN-γ组和MB43＋rIFN-γ组免疫鸡的脾只有个别淋巴细胞核浓缩、核崩解，少数滤泡萎缩变性坏死；胸腺损伤程度轻于MB43疫苗单独免疫组和非免疫对照组。免疫后1周，3个免疫组外周血CD8^＋T淋巴细胞含量均显著高于非免疫对照组，CD4^＋T淋巴细胞含量变化不明显；攻毒后第2周，3个疫苗免疫组CD4^＋、CD8^＋T淋巴细胞含量均显著升高，各组之间CD4^＋、CD8^＋T淋巴细胞含量无明显差异。证实，rFPV—IFN-γ和rIFN-γ可加强疫苗的细胞免疫和体液免疫应答。     

鸡传染性支气管炎病毒S1基因和鸡Ⅱ型干扰素基因在重组鸡痘病毒中的共表达

将鸡Ⅱ型干扰素（ChIFNγ）基因和鸡传染性支气管炎病毒S1基因同时插人到鸡痘病毒转移载体中，构建含有这2个基因的鸡痘病毒转移载体pSY—ChIFNγS1。采用脂质体法将该质粒转染鸡痘病毒感染的鸡胚成纤维细胞（CEF），经过8轮蓝斑筛选，得到纯化的能够同时表达鸡Ⅱ型干扰素和鸡传染性支气管炎病毒S1基因的重组鸡痘病毒rFPV—ChIFNγS1。rFPV—ChIFNγS1接种28日龄的SPF鸡1周后，可以检测到针对传染性支气管炎病毒S1基因的ELISA抗体，重组病毒接种鸡的CD4^＋、CD8^＋和γδTCR阳性T淋巴细胞的百分比含量显著高于非免疫对照鸡（P％0．05）；免疫4周后用传染性支气管炎LX4强毒株攻击，rFPV—ChIFNγS1免疫组仅有1只出现轻微的呼吸道症状（1／16），而非免疫对照组则有16只发病（16／16），并有2只出现死亡（2／16），表明rFPV—ChIFNγS1对接种鸡可以产生良好的保护效果。     

鸡传染性支气管炎重组鸡痘病毒基因工程疫苗对异源LTJ95Ⅰ株病毒攻击的免疫保护

将共表达鸡传染性支气管炎病毒（mv）S1基因和鸡干扰素-γ基因的重组鸡痘病毒（rFPV—IFN-γ S1）接种4周龄SPF鸡,免疫3周后用同源（LX4株）及异源强毒株（LTJ95I）攻毒,评价重组疫苗对异源病毒的保护作用。结果显示,重组疫苗接种1周后,免疫鸡产生抗IBV的抗体;而且外周血中CD4^＋和CD8^＋T淋巴细胞的含量略高于非免疫对照组;攻毒后,异源强毒株攻毒的免疫组CD4^＋T淋巴细胞呈下降趋势,并且该组低水平CD4^＋的状态一直持续到试验结束,而其他组CD4^＋T淋巴细胞均迅速上升,峰值达到14．5％;同源强毒株攻毒的免疫组CD8^＋T淋巴细胞呈高水平的表达,而其他组攻毒后均无明显变化;保护率结果显示,同源强毒株攻毒免疫组的发病率和死亡率为21．43％和0％,与其他各组相比均有显著差异;另外同源强毒株攻毒的免疫组病理损伤与异源强毒株攻毒的试验组相比明显减轻,其排毒时间和排毒量也均有所减少;强毒攻毒后所有试验组体重无显著差异。以上结果可以说明,重组疫苗能对同源强毒株产生较好的免疫保护,但不能对遗传关系较远的强毒株产生有效的免疫应答。     

表达鸡传染性支气管炎病毒S1基因重组鸡痘病毒对SPF鸡的免疫保护作用

将表达鸡传染性支气管炎病毒(IBV)S1基因的重组鸡痘病毒(rFPV-IBVS1)以5×106PFU剂量翅皮下注射接种4周龄的SPF鸡。血清抗体检测表明,该重组鸡痘病毒能刺激鸡体产生特异性抗体,外周血液中CD4 、TCRγδ T淋巴细胞比例显著高于对照组,而CD8 T淋巴细胞比例低于对照组。免疫后4周用1×103.0EID50的传染性支气管炎病毒LX4株进行攻毒,结果表明,重组鸡痘病毒免疫组与IB弱毒疫苗免疫保护率分别为12/16和13/16;攻毒后喉拭子IBV分离结果表明,IB弱毒疫苗和重组鸡痘病毒免疫组的IBV气管排毒时间比对照组缩短了2 d,病毒的分离率显著低于对照组;肾脏、气管、肺脏、腺胃、脾和肝脏的病理损伤也较对照组轻,而且病变持续时间缩短。     

鸡传染性支气管炎病毒S1基因和鸡II型干扰素基因在重组鸡痘病毒中的共表达

将鸡II型干扰素(ChIFNγ)基因和鸡传染性支气管炎病毒S1基因同时插入到鸡痘病毒转移载体中,构建含有这2个基因的鸡痘病毒转移载体pSY-ChIFNγS1。采用脂质体法将该质粒转染鸡痘病毒感染的鸡胚成纤维细胞(CEF),经过8轮蓝斑筛选,得到纯化的能够同时表达鸡II型干扰素和鸡传染性支气管炎病毒S1基因的重组鸡痘病毒rFPV-ChIFNγS1。rFPV-ChIFNγS1接种28日龄的SPF鸡1周后,可以检测到针对传染性支气管炎病毒S1基因的ELISA抗体,重组病毒接种鸡的CD4+、CD8+和γδTCR阳性T淋巴细胞的百分比含量显著高于非免疫对照鸡(P<0.05);免疫4周后用传染性支气管炎LX4强毒株攻击,rFPV-ChIFNγS1免疫组仅有1只出现轻微的呼吸道症状(1/16),而非免疫对照组则有16只发病(16/16),并有2只出现死亡(2/16),表明rFPV-ChIFNγS1对接种鸡可以产生良好的保护效果。     

重组鸡痘病毒表达的鸡IL-1β和IL-2以及cMGF对新城疫LaSota疫苗免疫效果的影响

将128只10日龄SPF鸡随机分成8组，每只免疫1PD50的新城疫LaSota疫苗；同时Ⅰ～Ⅵ组鸡分别皮下注射不同剂量的重组鸡痘病毒rFPV-IL-1β、rFPV-IL-2或cMGF，而Ⅶ组和Ⅷ组鸡分别皮下注射鸡痘病毒wt-FPV和PBS作为阴性对照和空白对照。结果，重组鸡痘病毒表达的IL-1β、IL-2或cMGF可以消除鸡痘病毒在免疫后第7d对雏鸡体重增长的影响；一定剂量的IL-1β和IL-2可使鸡脾中CD4^＋T细胞在免疫后第7d和CD8^＋T细胞在免疫后第14d的总体水平提高；免疫第21d新城疫F48E8强毒攻毒后，一定剂量的IL-1β和IL-2能提高免疫保护率，而cMGF却无此作用。结果表明，重组鸡痘病毒表达的IL-1β和IL-2在一定剂量下可增强新城疫LaSota疫苗的免疫效果。     

表达MDV gB和/或鸡γ干扰素基因的重组鸡痘病毒免疫效力试验

将表达鸡γ干扰素基因、表达MDV gB基因、共表达MDV gB和鸡γ干扰素基因的重组鸡痘病毒进行组合免疫观察在SPF鸡、狼山鸡中的免疫保护作用。在狼山鸡中随rFPV-gB剂量的减少，保护效力逐渐下降，而在SPF鸡中10^4与10^6PFU的rFPV-gB提供相同的保护效力，但存在减缓增重的副反应；在所有的疫苗组合中，由10^6PFU的rFPV-gB、10^5PFU的rFPV-IFN-Ⅱ和4000PFU HVT组成三价疫苗的保护效力最高且不影响增重，表明鸡γ干扰素既或降低重组鸡痘病毒的减缓增重的副反应，又具有免疫佐剂作用，与重组鸡痘病毒及HVT配合成疫苗是预防MD有效的冻干制剂。     

鸡传染性支气管炎重组鸡痘病毒基因工程疫苗对异源LT95Ⅰ株病毒攻击的免疫保护

将共表达鸡传染性支气管炎病毒(IBV)SI基因和鸡干扰素.丫基因的重组鸡痘病毒(rFPV-IFNγ S1)接种4周龄SPF鸡,免疫3周后用同源(LX4株)及异源强毒株(LTJ951)攻毒,评价重组疫苗对异源病毒的保护作用.结果显示,重组疫苗接种1周后,免疫鸡产生抗IBV的抗体;而且外周血中CD4+和CD8+T淋巴细胞的含量略高于非免疫对照组;攻毒后,异源强毒株攻毒的免疫组CD4+T淋巴细胞呈下降趋势,并且该组低水平CD4+的状态一直持续到试验结束,而其他组CD4+T淋巴细胞均迅速上升,峰值达到14.5%;同源强毒株攻毒的免疫组CD8+T淋巴细胞呈高水平的表达,而其他组攻毒后均无明显变化;保护率结果显示,同源强毒株攻毒免疫组的发病率和死亡率为21.43%和0%,与其他各组相比均有显著差异;另外同源强毒株攻毒的免疫组病理损伤与异源强毒株攻毒的试验组相比明显减轻,其排毒时间和排毒量也均有所减少;强毒攻毒后所有试验组体重无显著差异.以上结果可以说明,重组疫苗能对同源强毒株产生较好的免疫保护,但不能对遗传关系较远的强毒株产生有效的免疫应答.     

传染性支气管炎重组鸡痘病毒免疫鸡对LHLJ04X I株病毒攻击的免疫保护作用

将表达鸡IFN-γ基因和传染性支气管炎病毒S1基因的重组鸡痘病毒（rFPV-IFN-γ S1）接种SPF鸡后,用与S1基因亲本毒株具有相同致病型且遗传关系较近的现地分离株LHLJ04XI病毒进行攻击．评价重组疫苗对现地分离病毒的保护效果。结果显示,重组病毒在免疫后1周即可检出ELISA抗体,并且免疫组外周血CD4^＋、CD8^＋T淋巴细胞含量均有显著上升。当用LHLJ04XI株病毒及亲本毒LX4攻击后,免疫鸡的肝脏、肾脏、脾脏及肺脏等脏器的病理损伤程度明显轻于非免疫对照组,排毒时间缩短,攻毒后现地分离株攻击的免疫组的发病率为27.3％（3／11）,死亡率为9．1％（1／11）,亲本毒攻击的免疫组发病率为26．67％（4／15）,死亡率为6．67％（1／15）,两者没有明显差异,而非免疫对照组的发病率和死亡率分别为100％（11／11）和45．5％（5／11）,与免疫组相比差异显著,说明重组疫苗对免疫鸡具有较好的保护效果。体重测定结果表明,攻毒前重组疫苗免疫组和非免疫对照组的体重差异不显著（P〉0．05）,攻毒以后免疫组体重的增加幅度高于非免疫对照组。以上结果表明,共表达鸡IFN-^γ基因和传染性支气管炎病毒S1基因重组鸡痘病毒活载体疫苗能对异源现地分离株的攻击产生较好的免疫保护,同时也减轻了重组疫苗对体重增长的抑制作用。     

靶向新城疫病毒NP基因的shRNA重组腺病毒表达载体的构建及鉴定

为验证腺病毒载体在鸡胚成纤维细胞(CEF)及鸡胚中递送小干扰RNA的可行性,本实验利用共转染技术将表达针对新城疫病毒(NDV)NP基因shRNA的重组质粒同源重组到pGSadeno腺病毒载体系统,用重组腺病毒感染CEF和鸡胚,通过红荧光报告基因的表达情况和荧光定量PCR检测NP基因mRNA的表达对其进行鉴定,并通过细胞形态观察、血凝价的测定评价其在CEF和鸡胚上对NDV增殖的影响。实验结果显示重组腺病毒能够感染CEF,感染CEF后6h、9h、12h与对照组比较NP基因mRNA的表达量分别降低了3.2倍,25.6倍,2.57倍,并能够推迟NDV致细胞病变效应,抑制NDV在鸡胚上的增殖,延缓鸡胚的死亡。本实验构建的重组腺病毒能够在CEF和鸡胚上递送特异的shRNA,为在CEF中的RNA干涉研究开辟了新的递送途径。     

Differential cytokine gene expression in CD4+ and CD8+ T cell subsets of calves

The distinct patterns of cytokine expression in CD4+ and CD8+ T cells are well understood in mice and humans. However, little information is available about cytokine expression in bovine CD4+ and CD8+ T cells. In this study, mRNA expression of 19 different cytokines was analyzed in CD4+ and CD8+ T cells of calves with or without Concanavalin A (Con A) stimulation. CD4+ and CD8+ T cell populations were enriched to 98% purity by positive selection using magnetic cell sorting (MACS). CD4+ T cells spontaneously expressed the mRNAs of interleukin-1alpha (IL-1alpha), IL-1beta, IL-2, IL-6, IL-7, IL-8, IL-10, IL-18, IFN-gamma, TNF-alpha, TNF-beta and TGF-beta, and augmented the mRNA expression of IL-10, IFN-gamma and TNF-beta after Con A stimulation. The mRNAs of IL-3, IL-4, IL-5, IL-13 and GM-CSF were newly expressed in Con A-stimulated CD4+ T cells. CD8+ T cells displayed spontaneous mRNA expression of IL-6, IL-18, TNF-alpha, TNF-beta and TGF-beta, and newly expressed the mRNA of IL-2, IL-7, interferon-gamma (IFN-gamma) and GM-CSF after Con A stimulation. It was found that CD4+ T cells expressed the mRNA of 17 cytokines except for IL-12 and IL-15, while CD8+ T cells expressed only the mRNA of 9 cytokines after Con A stimulation. The profile of cytokine mRNA expression was substantially different in the CD4+ and CD8+ T cells of calves, indicating that CD4+ T cells can be distinguished from CD8+ T cells by the cytokine gene expression of IL-1alpha, IL-1beta, IL-3, IL-4, IL-5, IL-8, IL-10 and IL-13. Differential cytokine expression between CD4+ and CD8+ T cells serve to interpret an individual function of T cell subsets in the immune system of calves.     

In vitro effects of dexamethasone on bovine CD25+CD4+ and CD25−CD4+ cells

This paper investigates the in vitro effect of dexamethasone on bovine CD25^highCD4⁺, CD25^lowCD4⁺ and CD25⁻CD4⁺ T cells. Only a small percentage of bovine CD25^highCD4⁺ (2–4%) and CD25^lowCD4⁺ (1–2%) cells expressed Foxp3. Dexamethasone caused considerable loss of CD25⁻CD4⁺ cells, but it increased the relative and absolute numbers of CD25^highCD4⁺ and CD25^lowCD4⁺ lymphocytes, while at the same time reducing the percentage of Foxp3⁺ cells within the latter subpopulations. Considering all these, as well as the intrinsically poor Foxp3 expression in bovine CD25⁺CD4⁺, it can be concluded that the drug most probably increased the number of activated non-regulatory CD4⁺ lymphocytes. It has been found that changes in cell number were at least partly caused by proapoptotic effect of the drug on CD25⁻CD4⁺ cells and antiapoptotic effect on CD25^highCD4⁺ and CD25^lowCD4⁺ cells. The results obtained from this study indicate that the involvement of CD4⁺ lymphocytes in producing the anti-inflammatory and immunosuppressive effect of dexamethasone in cattle results from the fact that the drug had a depressive effect on the production of IFN-γ by CD25⁻CD4⁺ cells. Secretion of TGF-β and IL-10 by CD4⁺ lymphocytes was not involved in producing these pharmacological effects, because the drug did not affect production of TGF-β and, paradoxically, it reduced the percentage of IL-10⁺CD4⁺ cells.     

AA肉鸡血液CD3+、CD4+和CD8+T淋巴细胞的变化规律

采用流式细胞仪检测1、3、5、7、14、21、28、35、42、49日龄AA肉鸡血液中的CD3、CD4、CD8阳性T细胞比例。研究结果表明:1～5日龄T细胞逐渐进入血液参与细胞免疫,7、21日龄注射疫苗起免疫应答作用,28日龄后基本形成稳固的细胞免疫水平。     

FMDV结构基因P1的克隆与植物双元表达载体的构建

通过RT-PCR法获得阿克苏(Akesu/O/58)FMDV结构基因P1,将该基因克隆到pGEM-T Easy载体进行核苷酸序列测定。将P1基因、Kozak序列等插入中间表达质粒pB in438,构建重组中间表达载体pB inP1。采用三亲融合法构建植物双元表达载体pB inFMDV-P1。结果表明:P1基因为2 208 bp。重组中间表达载体pB inP1经BamHⅠ/SalⅠ双酶切、PCR扩增和序列测定,表明P1基因、Kozak序列等已插入pB inP1。在含50mg/L卡那霉素、25 mg/L链霉素和50 mg/L利福平的YEB培养基上筛选及对融合农杆菌质粒进行P1基因的PCR检测,证明植物双元表达载体pB inFMDV-P1构建正确。     

CD4+ and CD8+ T- lymphocytopenia in a filly with Pneumocystis carinii pneumonia

Decreased proportion of CD4+ and CD8+ T lymphocytes in peripheral blood likely contributed to susceptibility to Pneumocystis carinii in a foal. Cytological evaluation of bronchoalveolar lavage was required for identification of the pathogen and serial flow-cytometric analysis of peripheral blood lymphocytes documented transient low expression of CD4+ and CD8+ T lymphocytes. Although immunodeficiency is uncommon, it must be included in the differential diagnosis for patients suffering from chronic or opportunistic infections and may provide an indication for immunostimulant therapy.     

水貂和狐犬瘟热病毒F基因的克隆与序列分析

为探寻免疫失败的原因,对山东某养殖场免疫后的发病水貂和狐犬瘟热组织病料分别提取RNA进行RT-PCR扩增。将PCR得到的部分F基因克隆到pMD18-T载体上测序,并与疫苗株ND进行序列分析。结果表明,水貂和狐的CDV与OND的核苷酸同源性为98.6%9、8.6%,氨基酸同源性为98.0%9、8.0%。水貂和狐两者核苷酸同源性为98.0%,氨基酸同源性为95.9%。     

Canine CD20 gene

The human CD20 antigen, a 35kDa cell surface nonglycosylated hydrophobic phoshpoprotein is expressed consistently on almost all human B-cells, and its monoclonal antibody is used for the therapy on human B-cell lymphoma. In the present study, canine CD20 gene was cloned and sequenced, and the expression of CD20 mRNA was investigated in canine peripheral blood mononuclear cells (PBMCs), and lymph nodes from healthy dogs, and canine lymphoma cells. Using canine cDNA as a template, full-length of canine CD20 gene was sequenced by 5'-RACE and 3'-RACE methods. The full-length of the cDNA sequence of canine CD20 was 1239bp encoding 297 amino acids. The amino acid sequences of canine CD20 showed 73 and 68% sequence similarities with those of human and mouse, respectively. Canine CD20 was predicted to contain domains of amino acid sequences consisting of two extracellular domains (EM), four transmembrane domains (TM), and three intracellular domains (IC) as in human CD20. Canine CD20 mRNA was detected in PBMCs and lymph node from healthy dogs, and B-cells of canine lymphoma, but not in T-cell lymphoma cells and non-T and non-B-cell lymphoma cells by RT-PCR analysis. From these results, canine CD20 might be targeted for monoclonal antibody therapy against B-cell lymphoma of dogs.