实验性热应激对肉仔鸡免疫器官的影响

对实验性热应激肉仔鸡的免疫器官的组织学变化、超微组织学变化进行了动态观察，对热应激造成的免疫器官的细胞凋亡及免疫反应能力进行了检测。结果表明，热应激可引起免疫器官胸腺、脾脏、法氏囊的发育分化不良，使法氏囊指数、脾脏指数明显下降，胸腺指数虽有下降，但幅度较小；热应激对免疫器官的组织结构有显著影响，尤其对法氏囊和脾脏的影响更明显，主要表现为实质细胞的萎缩、消失性病变，但无明显的实质细胞崩解坏死、炎性细胞浸润、炎性充血等病理变化，并随热应激时间的延长而逐渐加重，最后以实质细胞几乎完全消失、间质结缔组织增生而纤维化告终。热应激可显著影响试验鸡血清新城疫病毒抗体滴度，与对照相比，其抗体滴度的峰值低，维持时间短，下降速度快；通过电镜观察和细胞凋亡的原位检测，证实热应激时免疫器官的淋巴细胞和巨噬细胞有凋亡现象，这种凋亡现象在早期尤其显著。     

实验性热应激对肉仔鸡免疫器官的影响

对实验性热应激肉仔鸡的免疫器官的组织学变化、超微组织学变化进行了动态观察,对热应激造成的免疫器官的细胞凋亡及免疫反应能力进行了检测.结果表明,热应激可引起免疫器官胸腺、脾脏、法氏囊的发育分化不良,使法氏囊指数、脾脏指数明显下降,胸腺指数虽有下降,但幅度较小;热应激对免疫器官的组织结构有显著影响,尤其对法氏囊和脾脏的影响更明显,主要表现为实质细胞的萎缩、消失性病变,但无明显的实质细胞崩解坏死、炎性细胞浸润、炎性充血等病理变化,并随热应激时间的延长而逐渐加重,最后以实质细胞几乎完全消失、间质结缔组织增生而纤维化告终.热应激可显著影响试验鸡血清新城疫病毒抗体滴度,与对照相比,其抗体滴度的峰值低,维持时间短,下降速度快;通过电镜观察和细胞凋亡的原位检测,证实热应激时免疫器官的淋巴细胞和巨噬细胞有凋亡现象,这种凋亡现象在早期尤其显著.     

鸭坦布苏病毒对雏鸭免疫系统的影响

为研究鸭坦布苏病毒(DTMUV)对雏鸭免疫系统的影响,本试验对5日龄雏鸭静脉接种DTMUV,并于接种后不同时间取雏鸭脾脏、胸腺、法氏囊进行组织病理学、抗原和凋亡检测。结果显示,DTMUV感染雏鸭的脾脏、胸腺、法氏囊均严重受损。接种DTMUV后4d,脾脏淋巴细胞减少,胸腺可见严重细胞崩解和大面积坏死区域,法氏囊滤泡轻度萎缩;接种后6d免疫器官病变最为严重,其中胸腺静脉严重栓塞,淋巴细胞变性坏死,空泡化也更加严重;接种后8d免疫器官病变均有所减轻,至16d,免疫器官结构基本恢复正常。通过免疫组织化学方法在感染雏鸭的脾脏、胸腺、法氏囊中均检测到DTMUV抗原;细胞凋亡试验显示DTMUV能够显著引起脾淋巴细胞凋亡。综上所述,DTMUV可严重损伤雏鸭免疫器官,且这种损伤常发生于感染早期,并于感染后8d出现好转。     

禽流感病毒与番鸭呼肠病毒感染番鸭免疫器官细胞凋亡的研究

应用原位末端标记法和免疫组化SABC法,分别以H9亚型禽流感和番鸭呼肠病毒单独感染或混合感染雏番鸭后1、3、5、7、10d对胸腺、法氏囊、脾脏细胞凋亡和P53的动态变化进行检测。结果显示,H9亚型AIV,MDRV单独感染和混合感染均可导致雏番鸭胸腺、法氏囊和脾脏出现淋巴细胞凋亡增多;病毒感染早期各免疫器官组织细胞凋亡明显,感染后期细胞凋亡量逐渐减少;混合感染组脾脏、胸腺细胞凋亡更为显著。P53表达的变化与细胞凋亡呈现相同变化规律,表明P53表达与病毒诱导的细胞凋亡机制密切相关。     

断喙应激对雏鸡胸腺细胞凋亡及相关凋亡蛋白表达的影响

为研究断喙应激对雏鸡胸腺细胞凋亡及相关凋亡蛋白表达的影响,采用电子显微镜技术、流式细胞术和免疫组织化学技术分析断喙对鸡胸腺淋巴细胞的细胞增殖、分化、凋亡及相关凋亡蛋白(Bcl-2和Bax)表达的影响.结果表明:采用电子显微镜技术观察到断喙对胸腺淋巴细胞产生明显的影响,断喙组胸腺细胞内可看到细胞核明显的应激反应,细胞核凝集,较致密,部分细胞核即将溶解,并出现一定数量的凋亡和坏死细胞;流式细胞仪检测表明对照组和断喙组的胸腺内淋巴细胞都是以G1期为主,但断喙组G1期淋巴细胞数量比试验组高;对照组和断喙组胸腺淋巴细胞凋亡率在断喙后5d时差异显著(P＜0.05);免疫组化结果表明断喙应激没有影响Bcl-2和Bax蛋白在免疫器官内的表达部位;但有降低Bcl 2在胸腺细胞内表达量的趋势;有提高Bax在胸腺细胞内表达量的趋势.结果表明断喙应激促进了雏鸡胸腺淋巴细胞凋亡.     

鸡传染性法氏囊病超强毒感染后SPF鸡免疫器官病理学观察

IBDV超强毒株LX株接种2周龄SPF雏鸡后，其致病性不同于经典强毒株CJ801株，它主要引起接种鸡全身性炎症反应，法氏囊、脾脏、盲肠扁桃体等免疫器官中大量异嗜性白细胞、巨噬细胞浸润，淋巴细胞严重坏死崩解，胸腺皮质严重萎缩、坏死，骨髓中造血细胞减少、巨噬细胞和脂肪细胞增生。在接种后14d法氏囊淋巴滤泡严重萎缩、淋巴细胞排空形成囊腺样结构，未见恢复正常，其它免疫器官形态基本恢复正常。电镜观察，接种后2和4d可见胸腺淋巴细胞胞浆浓集、染色质周边化形成新月形，表现细胞凋亡特征；在法氏囊坏死淋巴细胞胞浆中可见60nm大小呈晶格排列或散在的病毒粒子。研究初步探明了鸡传染性法氏囊病病毒超强毒的致病机理。     

新城疫病毒人工感染鸡诱导胸腺和法氏囊细胞凋亡的初步研究

本研究用新城疫病毒(NDV)参考强毒株F48E8感染鸡,通过光镜和电镜观察鸡的胸腺和法氏囊淋巴绌胞凋亡的形态学特征,并进行统计学分析。NDV感染鸡后,其胸腺和法氏囊淋巴细胞凋亡数量显著增加(P＜0．01)。实验结果说明NDV参考强毒株F48E8人工感染鸡后可以诱导胸腺和法氏囊淋巴绌胞凋亡。     

鸡感染J亚群禽白血病病毒的免疫抑制机理

通过人工接种建立了雏鸡感染J亚群禽白血病病毒（ALV-J）后发生免疫抑制的病理模型。对免疫抑制的机理进行了初步研究。结果表明：ALV-J感染早期可诱导胸腺、法氏囊的淋巴细胞凋亡，这种早期的淋巴细胞凋亡是胸腺和法氏囊萎缩的重要原因之一。病理组织学动态观察表明。ALV-J主要引起骨髓的髓系细胞灶状或弥漫性增生，病变导致骨髓机能受损，使机体免疫机能下降。是引起免疫抑制的根本原因。病毒感染组免疫器官均发生了严重的实质萎缩性病变．这种病变的发生除与骨髓的病变及淋巴细胞凋亡有关外。还与中后期淋巴细胞的坏死有关．从而导致严重的免疫抑制。ALV-J感染可引起免疫器官及部分内脏器官中嗜酸性粒细胞样的瘤细胞浸润增生，这可以作为病毒感染早期的病理诊断指标。     

传染性法氏囊病病毒人工感染诱导靶细胞细胞凋亡的研究

本试验借助透射电镜技术、琼脂糖凝胶电泳、流式细胞术和荧光染色技术对传染性法氏囊病病毒变异 Ｅ 株人工感染诱导的雏鸡法氏囊淋巴细胞和体外培养法氏囊细胞的细胞凋亡进行了较为详细的研究。结果表明， Ｉ Ｂ Ｄ Ｖ 感染后早期阶段，雏鸡法氏囊淋巴细胞和体外培养法氏囊细胞呈现典型细胞凋亡的形态学特征和生化特 征。 Ｉ Ｂ Ｄ Ｖ 感染雏鸡后２４～４８ ｈ 和感染法氏囊培养细胞后４～２４ ｈ，法氏囊淋巴细胞凋亡细胞数量显著增加，而正常淋巴细胞数量相应减少，揭示 Ｉ Ｂ Ｄ Ｖ 人工感染可以诱导雏鸡法氏囊淋巴细胞和体外培养法氏囊淋巴细胞的细胞凋亡。     

低水平添加蛋氨酸对雏鸡免疫器官的影响

本实验通过对胸腺、法氏囊和脾脏的观察和检测来进行研究蛋氨酸缺乏对雏鸡机体免疫器官和免疫功能的影响,具体如下:对法氏囊的检测研究:通过组织学进行观察,雏鸡从21日龄开始法氏囊淋巴滤泡内的淋巴细胞发生变化,出现减少现象,并且雏鸡皮质变薄,髓质变宽现象也逐渐凸显出来。对胸腺检测研究:通过组织学观察研究,试验组胸腺小叶淋巴细胞较之于对照组显著减少,并且胸腺小叶结构变得模糊;对脾脏检测研究:试验组雏鸡脾脏的红髓和白髓淋巴细胞与对照组相比有明显较少现象并且其组织学结构发生紊乱。     

鸡传染性法氏囊病的病理学研究

人工接种２８日龄非免疫鸡传染性法氏囊病病毒（ＩＢＤＶ）后,对感染鸡的法氏囊、胸腺、脾、盲肠扁桃体、哈德氏腺、肝、肾进行病理组织学检查。感染后４８ｈ,法氏囊淋巴组织最早出现坏死且长久存在。其他淋巴器官的病变出现较迟,程度轻微且恢复较快。ＩＢＤＶ单抗免疫荧光检测,法氏囊及其他淋巴器官中均检测到病毒,接种后１２ｈ法氏囊中即检出病毒,持续时间也最长（攻毒后１２ｄ）,其次是盲肠扁桃体（攻毒后８ｄ）。攻毒１３ｄ以后,上述器官均未检测到病毒。法氏囊粘膜上皮的扫描电镜观察,攻毒后２ｄ,上皮细胞肿胀,微绒毛减少或消失。攻毒后３ｄ,局部上皮细胞坏死、脱落,并向整个粘膜层扩展,攻毒后１０ｄ,上皮层基本修复。     

固始鸡中枢免疫器官细胞和自然凋亡细胞超微结构研究

应用透射电子显微镜技术,对固始鸡17日龄胚胎、4周龄和19周龄固始鸡正常发育的中枢免疫器官超微结构进行了研究。结果表明,固始鸡胚胎胸腺和法氏囊超微结构不同于4周龄和19周龄固始鸡;在中枢免疫器官内免疫细胞存在着自然凋亡现象,主要表现为细胞核的变化,其次是线粒体增生。核质凝集为新月形、C字形、圆环形、花瓣状等多种形态,凋亡细胞裂解为凋亡小体,最后被巨噬细胞吞噬。     

锌对雏番鸭淋巴器官中肥大细胞数量的影响

选择1日龄健康雏番鸭45只,随机分为3组,分别喂以每kg含锌离子20mg、40mg、200mg的饲料,饲养期为45d。于15日龄、30日龄和45日龄每组随机宰杀5只,取法氏囊、脾脏、胸腺,Carnoy法固定,甲苯胺蓝染色,显微镜观察肥大细胞数量的变化规律。结果表明：15日龄时,低锌日粮组鸭子胸腺和脾脏的肥大细胞数量均比另外两组高,（P〉0.05）,而法氏囊中低锌日粮组肥大细胞数量比另外两组明显高（P〈0.01）。30日龄时,低锌日粮组鸭子胸腺、脾脏和法氏囊中肥大细胞数量均比高锌日粮组显著增多（P〈0.05）,而与正常锌日粮组相比,差异不显著（P〉0.05）。45日龄时,法氏囊高锌日粮组与低锌日粮组和正常锌日粮组差异显著（P〈0.05）;脾脏各组间差异不显著（P〉0.05）,但高锌日粮组肥大细胞数量最多;胸腺低锌日粮组与高锌日粮组和正常锌日粮组差异极显著（P〈0.01）。因此,锌具有稳定免疫器官中肥大细胞数量的重要作用,但长时间添加高剂量锌反而会增加肥大细胞数量。     

胸腺素α_1对墟岗黄鸡免疫器官组织学结构的影响

本试验研究了不同剂量的胸腺素α1(Tα1)对墟岗黄母鸡免疫器官指数和组织学结构的影响。结果表明:0.015mg/kg体重剂量的Tα1可显著提高鸡免疫器官指数,可使胸腺皮质增宽,髓质胸腺小体数和胸腺细胞数增加;脾脏胸腺依赖区和法氏囊依赖区细胞增殖;高剂量Tα1则引起法氏囊髓质局部细胞变性和坏死。     

鸭瘟病毒强毒株在感染鸭实质器官内的增殖与分布

鸭瘟病毒(DPV)CHv强毒株经皮下注射、滴鼻和口服3种途径分别感染20日龄天府肉鸭,于攻毒后10、30、60、90min以及4、12、48、72h和9、15d每组分别剖杀2只鸭,采集心、肝、脾、肺、肾、脑、胸腺、法氏囊、哈德氏腺等实质器官,应用TaqMan-MGB探针实时荧光定量PCR对DPV在这些器官的分布和增殖进行检测。结果表明,DPV分布到具体器官的速度与感染的途径、鸭的解剖结构密切相关,其中皮下注射是DPV分布到各实质器官速度最快的途径。30min于皮下感染鸭的肝、脾、胸腺、法氏囊、哈德氏腺、肺、脑、肾,口服感染鸭的肺和法氏囊,滴鼻感染鸭的心脏和哈德氏腺均检测到DPV-DNA;90min所有受检样品中检测到DPV-DNA。鸭抗DPV感染的免疫器官的重要性依次是脾、胸腺、法氏囊和哈德氏腺,30min内DPV-DNA分布到脾、胸腺、法氏囊的速度和数量决定了DPV感染的潜伏期和疾病的严重程度。不同途经感染鸭的相同器官在同一时间内的DPV-DNA拷贝数大多以皮下感染鸭为最高。DPV致死鸭的法氏囊和肾是DPV-DNA含量最高的实质器官。     

Lymphocytic depletion of bursa of Fabricius and thymus in chickens inoculated with Escherichia coli

Specific-pathogen-free 10-week-old chickens were inoculated via the air sac with Escherichia coli and showed lymphocytic depletion of bursa of Fabricius and thymus. In experiment I, chickens were necropsied at 12 and 24 hours, 2, 3, and 5 days after inoculation. At 12 hours after inoculation there was lymphocytic depletion in the medulla of lymphoid follicles of the bursa. At 24 hours after inoculation there was lymphocytic depletion also in the cortex of follicles and edema in interfollicular interstitium and follicular medulla. At 2 and 3 days after inoculation there were more marked lymphocytic depletion in medulla and cortex, and fibrosis in interfollicular interstitium. Partial repopulation of follicles with lymphocytes was seen at 5 days after inoculation. In the thymus, lymphocytic depletion occurred in the cortex. At 12 hours after inoculation, lymphocytic necrosis increased in number more than that of control chickens. The width of the cortex and medulla decreased. At 24 hours after inoculation, lymphocytic necrosis increased further. At 2 to 5 days after inoculation, the boundary between the cortex and medulla of lobules was obscure and cellular elements of the cortex and medulla were mingled. In experiment II, chickens were necropsied as in experiment I and also at 8 and 14 days after inoculation. The relative weights of the bursa and thymus reduced rapidly to minimal relative weights at 8 days after inoculation. At 14 days after inoculation, both bursa and thymus had normal relative weights and histological structures. These findings indicate that E. coli infection may induce transient lymphocytic depletion of lymphoid tissues in the chicken.     

Detection of in ovo-inoculated infectious bronchitis virus by immunohistochemistry and in situ hybridization with a riboprobe in epithelial cells of the lung and cloacal bursa

In situ hybridization and immunohistochemistry were utilized to identify tissues infected in ovo with infectious bronchitis virus (IBV). Chicken embryos were inoculated in ovo (chorioallantoic sac) with the Arkansas (Ark) serotype of IBV at 18 days of age. At 24, 48, 72, and 120 hr postinfection (HPI), bursa, lung, spleen, heart, and thymus were collected, fixed in 10% neutral buffered formalin, and paraffin embedded. The digoxigenin-labeled antisense S1 riboprobe detected viral mRNA in the cytoplasm of respiratory epithelial cells in the primary bronchus at 24, 48, and 72 HPI. Viral mRNA was detected in bursa samples collected at 48 hr. Immunohistochemistry detected viral antigens in epithelial cells of the parabronchi and bursal tissues at 24 and 48 hr, respectively. No viral mRNA or antigen was detected by in situ hybridization or immunohistochemistry, respectively, in heart, thymus, or spleen at any time after inoculation. On the basis of these data, IBV apparently initially infects lung tissue, then migrates to and infects cells of the bursa. These results indicate that in situ hybridization can be useful in detection of IBV-infected chickens and in understanding the pathogenesis and virulence of IBV infection.     

Developmental changes in cell proliferation and apoptosis in the normal duck bursa of Fabricius

The aim of this work was to investigate developmental changes in cell proliferation and apoptosis in normal duck bursa of Fabricius using flow cytometry and immunohistochemistry. Studies were carried out on Tianfu ducks on days 24 and 27 of embryogenesis (E24 and E27) along with days 20, 70, and 200 of postnatal development (P20, P70, and P200). Results showed that the percentage of G₀/G₁ bursa cells significantly increased between E24 and P200 while the percentage of cells in the S phase or G₂ + M phase as well as the proliferating index obviously decreased during the same period. Proliferation cell nuclear antigen was detected in lymphocyte and interfollicular epithelium. The proliferative lymphocyte density tended to decrease from E24 to P200. Apoptotic bodies in macrophages, free apoptotic bodies, or nuclei with condensed chromatin in lymphocytes in follicles were identified by transferase-mediated dUTP nick-end labeling. Both flow cytometry and microscopic analysis reveal that the proportion of apoptotic cells and apoptotic lymphocyte density increased from E24 to P20, fell on P70, then rose again on P200. Our foundings demonstrate that cell proliferation decreases and apoptosis increases with age. These changes may account for duck bursa development and involution.     

人工感染鸭病毒性肠炎急性病例细胞凋亡的电镜研究

应用透射电镜和超薄切片技术观察鸭病毒性肠炎病毒（Duck Enteritis Virus，DEV）CH强毒株人工感染成年鸭各组织器官的形态学特征。结果表明，脾脏、胸腺、法氏囊、十二指肠固有层中淋巴细胞除了坏死变化外还有很明显的凋亡变化，两者往往同时存在。疾病过程中，淋巴细胞凋亡数量明显增多。凋亡细胞的形态学改变是细胞体积缩小，细胞器结构正常，染色质初期浓集成团，聚集于核膜的周边，随后出现染色质凝聚，核碎裂以及凋亡小体形成等现象。淋巴细胞的坏死和凋亡共同造成了淋巴细胞的大量损耗，淋巴细胞的这种变化可能在鸭病毒性肠炎的发病机制中起着重要的作用。研究结果表明DEV急性感染可诱导成年鸭体内淋巴细胞的凋亡。     

Distribution of immunoglobulin and secretory component containing cells in chickens

Distribution of immunoglobulin (Ig)-containing cells and secretory component in internal organs of two 15-day-old embryos and 17 chickens, 1 to 480 days old, were examined by fluorescent antibody technique. In 15-day-old embryos, Ig-containing cells were not found in gut, bursa, spleen, or thymus. The bursa of Fabricius synthesized IgM, IgG, and IgA in as young as 1-day-old chicks. In extrabursal organs, IgM-containing cells were already present in intestine of 1-day-old chicks, but IgA-containing cells appeared in intestine, thymus, and spleen between the 3rd and 7th day after hatching. Very few IgG-containing cells were in intestine on the 3rd and 7th day after hatching. Secretory component was found in epithelial surfaces of intestine and ductus choledochus of most chickens examined. The presence of secretory component and IgA-containing cells in intestine supported the existence of secretory-immunologic system in chickens.