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1.
山羊咽扁桃体和咽鼓管扁桃体的组织结构观察   总被引:2,自引:0,他引:2  
选取健康10月龄奶山羊10头,断头宰杀后取咽扁桃体和咽鼓管扁桃体,应用组织学光镜和电镜制片技术研究咽扁桃体和咽鼓管扁桃体的显微和亚显微组织结构.结果表明:山羊咽扁桃体和咽鼓管扁桃体的黏膜上皮主要由2~3层多边形上皮细胞组成,部分区域只有单层扁平细胞,相邻上皮细胞间空隙很大,上皮细胞表面有丰富的微绒毛.上皮细胞之间和黏膜上皮下方固有层内有大量淋巴细胞浸润.扁桃体的实质部分由数个次级淋巴小结和弥散淋巴组织构成,弥散淋巴组织中有大量分布的淋巴管和毛细血管后微静脉.此外,在紧贴黏膜上皮细胞下方的固有层和淋巴滤泡中可观察到少量的树突状细胞.结果提示山羊的咽扁桃体和咽鼓管扁桃体可作为鼻腔免疫的主要诱导位点和效应部位.  相似文献   

2.
Background: Human Cytomegalovirus(HCMV) infections can be found throughout the body, especially in epithelial tissue. Animal model was established by inoculation of HCMV(strain AD-169) or coinoculation with Hepatitis E virus(HEV) into the ligated sacculus rotundus and vermiform appendix in living rabbits. The specimens were collected from animals sacrificed 1 and a half hours after infection.Results: The virus was found to be capable of reproducing in these specimens through RT-PCR and Western-blot.Severe inflammation damage was found in HCMV-infected tissue. The viral protein could be detected in high amounts in the mucosal epithelium and lamina propria by immunohistochemistry and immunofluorescense.Moreover, there are strong positive signals in lymphocytes, macrophages, and lymphoid follicles. Quantitative statistics indicate that lymphocytes among epithlium cells increased significantly in viral infection groups.Conclusions: The results showed that HCMV or HEV + HCMV can efficiently infect in rabbits by vivo ligated intestine loop inoculation. The present study successfully developed an infective model in vivo rabbit ligated intestinal Loop for HCMV pathogenesis study. This rabbit model can be helpful for understanding modulation of the gut immune system with HCMV infection.  相似文献   

3.
Local immunity of the respiratory mucosal system in chickens and turkeys   总被引:1,自引:0,他引:1  
This review article presents fundamental mechanisms of the local mucosal immunity in selected regions of the respiratory tract in healthy birds and in some pathological conditions. The respiratory system, whose mucosa come into direct contact with microorganisms contaminating inhaled air, has some associated structures, such as Harderian gland (HG), conjunctive-associated lymphoid tissue (CALT) and paranasal glands (PG), whose participation in local mechanisms of the mucosal immunity has been corroborated by numerous scientific studies. The nasal mucosa, with structured clusters of lymphoid tissue (NALT - nasal-associated lymphoid tissue) is the first to come into contact with microorganisms which contaminate inhaled air. Lymphoid nodules, made up of B cells with frequently developed germinal centres (GC), surrounded by a coat of CD4+ cells, are the major NALT structures in chickens, whereas CD8+ cells are situated in the epithelium and in the lamina propria of the nasal cavity mucosa. Studies into respiratory system infections (e.g. Mycoplasma gallisepticum) have shown the reactivity of the tracheal mucosa to infection, despite a lack of essential lymphoid tissue. Bronchus-associated lymphoid tissue (BALT) takes part in bronchial immune processes and its structure, topography and ability to perform defensive function in birds is largely age-dependent. Mature BALT is covered by a delicate layer of epithelial cells, called follicle-associated epithelium (FAE). Germinal centres (GC), surrounded by CD4+ cells are developed in most mature BALT nodules, while CD8+ lymphocytes are dispersed among lymphoid nodules and in the epithelium, and they are rarely present in GC. Macrophages make up the first line of defence mechanisms through which the host rapidly responds to microorganisms and their products in the respiratory mucosal system. Another very important element are polymorphonuclear cells, with heterophils being the most important of them. Phagocytic cells obtained from lung lavages in birds are referred to as FARM (free avian respiratory macrophages). Their number in chickens and turkeys is estimated to be 20 times lower than that in mice and rats, which indicates a deficit in the first-line of defence in the birds' respiratory system. There are numerous B cells and antibody secreting cells (ASC) present throughout the respiratory system in birds. Their role comes down to perform antigen-specific protection by producing antibodies (IgM, IgY or IgA class) as a result of contact with pathogenic factors.  相似文献   

4.
The aim of this study was to characterise the morphological and histochemical features of equine nasopharyngeal tonsillar tissue. Nasal and oropharyngeal tonsillar tissue has been described as the gatekeeper to mucosal immunity because of its strategic location at the entrance to the respiratory and alimentary tracts. A combination of light, scanning and transmission electron microscopy has revealed the presence of follicle-associated epithelium (FAE) overlying lymphoid tissue of the equine nasopharyngeal tonsil caudal to the pharyngeal opening of the guttural pouch. Membranous microvillus (M) cells were identified in the FAE on the basis of short microvilli, an intimate association with lymphocytes, cytoplasmic vimentin filaments and epitopes on the apical surface reactive with lectin GS I-B4 specific for alpha-linked galactose. CD4-positive lymphocytes were scattered throughout the lamina propria mucosae as well as forming dense aggregates in the subepithelial part. The central follicular area was heavily populated with B lymphocytes and the dome and parafollicular areas contained both CD4- and CD8-positive lymphocytes. CD8-positive lymphocytes were also present in the epithelium and, together with B lymphocytes, in small numbers in the lamina propria mucosae. These observations indicate that the nasopharyngeal tonsil is potentially an important mucosal immune induction site in the horse and an appropriate target for intranasally administered vaccines.  相似文献   

5.
The palatine tonsils of five young horses formed 10-12 cm elongated follicular structures extending from the root of the tongue on either side to the base of the epiglottis and lateral to the glossoepiglottic fold. The stratified squamous non-keratinized epithelium of the outer surface was modified into crypts as reticular epithelium by heavy infiltration of lymphoid cells from underlying lymphoid follicles. In places, lymphoid tissue reaching almost to the surface and with only one to two cell layers intact was identified as the lymphoepithelium. Langerhans cells with Birbeck granules were interspersed between epithelial cells. Lymphoid tissue organized in lymphoid follicles constituted the parenchyma of the palatine tonsil. CD4-positive cells were more numerous and CD8-positive lymphocytes less numerous compared with their distribution in the lingual tonsil. B cells and macrophages were also more numerous than in the lingual tonsil and lectins showed a different pattern of attachment. M cells were not observed. High endothelial venules with well-developed vesiculo-vacuolar organelle had structural evidence of transendothelial and interendothelial migration of lymphocytes. Striated muscles as seen in the deeper lamina propria mucosae of the lingual tonsil were absent. The immunohistological and ultrastructural characteristics of the equine palatine tonsil are similar to those of humans but differ from those of the lingual tonsil and are consistent with a role as an effector and inductor immunological organ.  相似文献   

6.
The tubal tonsil of the horse surrounds the pharyngeal opening of the eustachian tube and is lined by pseudostratified columnar ciliated epithelium interspersed with areas of follicle-associated epithelium (FAE) heavily infiltrated by lymphocytes but devoid of goblet and ciliated cells. Scanning and transmission electron microscopy revealed microvillous cells and cells with features characteristic of M cells such as reduced microvilli or depressed bare surface, more numerous mitochondria, small vesicles and lysosomes, as well as vimentin filaments and epitopes specific for GS 1-B4 as previously seen in the nasopharyngeal tonsil. M cells were also identified in areas of respiratory epithelium not associated with lymphoid follicles and appeared to be the nasal mucosal counterparts of recently described intestinal villous M cells in the mouse. The underlying lymphoid tissue of the FAE was generally organized as solitary lymphoid follicles without germinal centres in contrast to the diffuse and large amount of organized lymphoid follicles with germinal centres that characterize the nasopharyngeal tonsil. CD8+ T and B-lymphocytes were much fewer than in the nasopharyngeal tonsil. High endothelial venules were mainly oriented towards the parafollicular area and contained much fewer endothelial pores and vesiculo-vacuolar organelles. Finally, scattered small clusters of mucus acini and striated muscles were other features that differentiated the tubal and nasopharyngeal tonsils.  相似文献   

7.
Scanning electron microscopy of lymphoid tissue in the large intestine of three germfree calves (age 3, 6, and 7 days) revealed two different units: propria nodules and lymphoglandular complexes (LGC). Propria nodules had lymphoid tissue predominantly in lamina propria and were covered by distinct follicle-associated epithelium which lacked goblet cells; nodules were surrounded by wide crypts, which were also lined by follicle-associated epithelium towards the luminal side. Lymphoglandular complexes had lymphoid follicles in the tunica submucosa; epithelial diverticulae extended through the muscularis mucosae branching into the lymphoid nodule. In centers of lymphoglandular complexes, protrusions of lymphoid tissue were covered with distinct follicle-associated epithelium. By transmission electron microscopy cells compatible with M cells in the small intestine of calves and cells with characteristics of both enteroabsorptive and M cells were found. Follicle-associated epithelium of propria nodules and lymphoglandular complexes differed only in the relative frequency of cell types.  相似文献   

8.
SUMMARY A disease with clinical signs and histological lesions similar to malignant catarrhal fever in cattle was transmitted from Rusa deer (Cervus timorensis) to rabbits. This was accomplished on 3 separate occasions, and the disease was serially passaged in rabbits up to 11 times. The clinical signs in affected rabbits were pyrexia, depression, anorexia, mucopurulent conjuctivitis, nasal discharge and diarrhoea. These signs were seen in 27 of 38 inoculated rabbits with the mean incubation period being 12 days (range 8 to 20 days). Histologically, affected rabbits exhibited mononuclear perivascular cuffing and vasculitis in the brain, heart, liver and kidney. Lymph nodes and spleen showed destruction and loss of mature lymphocytes and lymphoid follicles and an increased number of large lymphoblastoid cells. These clinical signs and lesions were not detected in control rabbits. The disease was not transmitted to cattle, sheep, guinea pigs or mice, nor was an agent isolated in cattle, deer or rabbit tissue cultures, or in chicken embryos.  相似文献   

9.
Regional Histological Variations of the Nasal Mucosa of Cattle   总被引:1,自引:1,他引:0       下载免费PDF全文
Aspects of the histology of the nasal mucosa of calves from four to six months of age have been described.

The functional significance of the type of epithelium, its thickness, the degree of neutrophil invasion, and its relationship to the numbers of Pasteurella haemolytica in the nasal cavity have been discussed. In addition, the arrangement and depth of glands in the lamina propria and the presence of lymph follicles have been described.

  相似文献   

10.
分泌IgA和IgG的浆细胞是黏膜免疫系统中两种重要的效应细胞。本研究旨在探究分泌IgA和IgG的浆细胞在家兔鼻腔中的分布特征。以20只健康成年家兔为研究对象,根据硬腭褶皱和牙齿特征,依次将家兔鼻腔分为Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ 5段,运用组织学、免疫组织化学、图像分析及统计学方法,对分泌IgA和IgG的浆细胞在家兔鼻腔中的分布特征进行了详细的研究。免疫组化结果显示:分泌IgA和IgG的浆细胞在家兔鼻腔每段都有分布,主要弥散分布于鼻黏膜固有层中;其形态呈圆形或卵圆形,核一般位于细胞一侧,胞质丰富呈阳性反应。统计结果显示:分泌IgA和IgG的浆细胞在鼻腔不同段的分布密度由高到低依次是:鼻腔第Ⅳ段、第Ⅴ段、第Ⅲ段、第Ⅱ段、第Ⅰ段。其中分泌IgA的浆细胞在鼻腔Ⅲ、Ⅳ、Ⅴ段的分布密度显著高于鼻腔Ⅰ、Ⅱ段(P<0.05),在上颌鼻甲、鼻中隔和筛鼻甲的分布密度显著高于上鼻甲(P<0.05);与分泌IgA的浆细胞相比,分泌IgG的浆细胞除鼻腔第Ⅳ段的分布密度显著高于鼻腔Ⅲ、Ⅴ段(P<0.05)外,其分布变化趋势基本与分泌IgA的浆细胞类似。结果证明,分泌IgA和IgG的浆细胞弥散分布于家兔每段鼻腔的鼻黏膜固有层中,有利于SIgA和IgG分子在整个鼻黏膜形成完整的保护屏障;分泌IgA和IgG的浆细胞主要分布在家兔鼻腔Ⅲ、Ⅳ、Ⅴ段及上颌鼻甲、筛鼻甲和鼻中隔,提示这些区域是家兔鼻腔免疫的重要效应部位。本研究为家兔呼吸系统疾病的预防及进一步探讨家兔鼻腔免疫应答的机制提供重要的理论依据。  相似文献   

11.
Gut-associated lymphoid tissue (GALT) in the large intestine was characterized in 12 calves (10 to 84 days old) obtained at necropsy (7, group A) or healthy animals (5, group B). Patches of mucosal lymphoid follicles were in all calves at ileocecal entrances (ICE), 23-42 cm distal to the ICE in the proximal loop of the ascending colon (proximal colon [PC] patch), and in the terminal rectum. PC patches varied from 8 to 30 cm in length. Solitary lymphoid follicles were found in the cecum of three calves, between the ileocecal entrances and the PC patch in four calves, adjacent to the PC patch in all calves, and in the ampulla recti. GALT occupied 7.8% of the large intestinal wall in animals of group A: 0.6% at the ileocecal entrance, 4.8% in the proximal colon, and 2.4% in the rectum. There were two different types of mucosal lymphoid follicles in group B: propria nodules with lymphoid follicles predominantly in the lamina propria, and lymphoglandular complexes with lymphoid follicles in the submucosa. In three 3-, 6-, and 7-day-old, germfree calves, distinct follicle-associated epithelium covered propria nodules and covering folds in depths of the lymphoglandular complexes; it was characterized by numerous intraepithelial cells and lack of goblet cells.  相似文献   

12.
In sheep, the pharyngeal first defence line against oral and inhaled antigens is organized in six tonsils. Since tonsils are regarded as secondary lymphoid tissue and part of the acquired immune system which is subjected to induction through contact with antigens, an evaluation of the different lymphocyte populations in tonsils is useful to determine a tendency of the specific tonsils to more inductive or more effective immunity. By means of immunohistochemistry, different lymphocyte populations were quantified and localized using a panel of eight antibodies, i.e. anti-CD45, anti-CD21, anti-CD2, anti-CD3, anti-CD4, anti-CD8, anti-WC1 and anti-Ki67. The CD21+ B lymphocytes were localized within the tonsillar lymphoid follicles. The CD2+/CD3+ T lymphocytes were numerous in the interfollicular regions and were aligned underneath and within the epithelium but were also observed at the CD21+ pole of the lymphoid follicles. Near the lingual and tubal tonsils, and the tonsil of the soft palate, the CD45+ cells around the seromucous glands and in the lamina propria were mainly CD3+ T cells. In all tonsils, the WC1+ gamma delta T cells formed a small lymphocyte population which harboured the lamina propria and the interfollicular region. The relative percentages of the different lymphocyte populations of the large palatine and pharyngeal tonsils, which are macroscopically the most developed, were comparable. In contrast, the lingual tonsil was significantly different from the other tonsils not only by its small size and lack of lymphoid follicles, but also by the lymphocyte populations. Based on the lymphocyte populations, the ovine tonsils can be divided in three groups with the tonsil of the soft palate, the tubal and paraepiglottic tonsil forming an intermediate between the palatine and pharyngeal tonsils as true tonsils on the one side, and the lingual tonsil as a scattered lymphocyte aggregation on the other side.  相似文献   

13.
The distribution of B cells in the lymphoid organs of the goat was studied using a panel of 13 monoclonal antibodies (mAbs) developed against different markers for bovine B cells. Samples of mesenteric lymph nodes, jejunal and ileal Peyer's patches, duodenum, jejunum, ileum, colon, caecum and rectum were taken from four 7-month-old male Murciano-granadina goats using the avidin-biotin-peroxidase (ABC) method on frozen sections as described by Hsu et al. (1981). The mAbs against immunoglobulins (Ig) recognized a large number of cells, particularly in the light zones of the germinative centres of the lymphoid follicles, regardless of the isotype against which they were directed. However, the greatest numbers of B cells in the germinative centres and outer coronas of the lymphoid follicles of the lymph node, spleen and Peyer's patches were recognized by mAbs against the L lambda chain of Ig and against IgM. This was also the case in other locations where B cells were abundant, such as the medulla of the lymph node and the dome of the Peyer's patches. These mAbs recognized not only B lymphocytes but also plasma cells, showing an intracytoplasmatic reaction (numerous in the spleen red pulp and the intestinal lamina propria when mAbs were used against the L lambda chain of the Ig, scarce in the intestinal lamina propria when used against IgM and scarce in spleen red pulp and numerous in the intestinal lamina propria when mAbs against IgA were used). The mAbs BAQ44 A, GC65 A and GB25 A are of interest because, besides marking cells in the B areas where lymphocytes show surface Ig, they give a positive reaction in areas where there are Ig-cells (the dark zone of the germinative centre) and do not immunostain plasma cells. Thus, these mAbs recognize a surface marker which is not an Ig.  相似文献   

14.
鸡肠道相关淋巴组织是粘膜相关淋巴组织的主要组成部分 ,是防止肠道病原感染的第一道防线。其中的肠道上皮、上皮间淋巴细胞、粘膜固有层淋巴组织在肠道免疫功能的调节方面起着重要的作用。本文就鸡肠道免疫研究进展做一综述。  相似文献   

15.
Light and electron microscope studies were conducted on the nasopharynx and the nasopharyngeal tonsil of 15 young horses. The nasopharynx and nasopharyngeal tonsil was lined with pseudostratified columnar ciliated epithelium and goblet cells. The lymphoepithelium of the nasopharyngeal tonsil was folded forming crypts, the mucosa of which was modified into follicle associated epithelium characterized by stratified cuboidal epithelium, loss of cilia, absence of goblet cells and infiltration of lymphocytes. The lamina propria mucosae of the nasopharyngeal tonsil contained well-developed lymphoid tissue and clusters of seromucus acini. Scanning electron-microscopy revealed a dense mat of cilia covering the nasopharynx and nasopharyngeal tonsil. The follicle-associated epithelium consisted of different populations of microvillus cells in addition to M cells with very short microvilli and a few squamous and intermediate cells. Microvillus cells in the deeper part of the FAE had larger microvilli and their cytoplasm contained a dense population of mitochondria, smooth and rough endoplasmic reticulum, Golgi complexes and lysosomes. The flat surfaced M cell had a more electron-dense cytoplasm and contained small supranuclear vacuoles in addition to the organelles seen in microvillus cells.  相似文献   

16.
The tonsil of the soft palate was an oval, flat structure located centro-rostrally on the oral surface of the soft palate. Its stratified squamous non-keratinized epithelium was perforated by holes or small crypts the deeper parts of which were loosely spongiform inter-digitated with lymphoid tissue. These unusual features have not previously been reported in tonsils of any species. Crypts and reticulated epithelium as found in the lingual and palatine tonsils were not observed. Lectins showed varying affinities for specific layers of the epithelium. M cells were not observed. A few Langerhans cells were distributed among surface epithelial cells. Lymphoid tissue was arranged loosely and in isolated lymphoid follicles in the subepithelial lamina propria mucosae. Although IgA+ cells and macrophages were proportionately more numerous the amount of lymphoid tissue was much less than in the lingual and palatine tonsils. Most of the follicular germinal centres lacked a darkly stained corona. CD4 positive were more numerous than CD8+ lymphocytes and were distributed in the parafollicular and inter-follicular areas. Large clusters of mucus acini positive for glycogen, acidic and neutral mucopolysaccharides separated lymphoid tissue from deeply placed striated muscle. Only a few high endothelial venules were observed in the parafollicular and inter-follicular areas. These had relatively few vesiculo vacuolar or other organelles in their high endothelial cells and few lymphocytes attaching to their walls.  相似文献   

17.
Immunohistological characterisation of ovine rectal tissue has revealed the presence of lymphoid follicles, predominantly in the submucosa, that closely resemble those found in intestinal Peyer's patches (PPs). Distinct T (CD4+, CD8+, gammadelta-TCR+) and B (CD21+, CD45R+) lymphocyte staining patterns were observed within and around follicles of the rectal mucosa. In addition, IgA+ and IgE+ cells were also found at this tissue site, with both phenotypes commonly residing in the lamina propria. RT-PCR examination of the cytokines expressed in the rectal mucosal tissue revealed consistently high levels of TGFbeta and IL-8 mRNA, low levels of IL-2 mRNA and no detectable IL-4 mRNA. The presence of lymphoid follicles, IgA+ plasma cells and IgA-inducing cytokines in rectal tissue of sheep indicate that this may be a suitable route for delivering mucosal vaccines.  相似文献   

18.
CD3+是T细胞群的重要表面标志,呼吸道黏膜下分布的CD3+淋巴细胞作为抗感染黏膜免疫的基础,在保护机体抵抗呼吸道感染中发挥重要作用。为了解黄牛呼吸道CD3+淋巴细胞和淋巴组织的分布,本研究运用HE染色法和免疫组织学方法对5头7岁健康婆罗门黄牛的鼻黏膜、气管、肺内支气管及肺脏组织的CD3+淋巴细胞和淋巴组织的分布进行了研究。结果显示,黄牛的鼻黏膜、气管、肺内支气管和肺脏组织中均分布有CD3+淋巴细胞,且主要分布于黏膜上皮间及其下方固有层中及腺体周围;在鼻黏膜和肺脏组织中分布有CD3+淋巴细胞形成的弥散淋巴组织。牛呼吸道中CD3+淋巴细胞数量在鼻黏膜和肺脏组织中分布最多,气管黏膜、肺内支气管黏膜次之。本试验结果明确了CD3+淋巴细胞在黄牛呼吸道中的分布谱,表明黄牛呼吸道具备引发局部黏膜免疫的基础条件,为牛呼吸道黏膜免疫及呼吸道疾病防治研究提供了数据支撑。  相似文献   

19.
雏鸡感染IBDV后法氏囊显微和超微结构的观察   总被引:1,自引:0,他引:1  
运用光镜、电镜技术,观察了雏鸡实验感染传染性法氏囊病病毒(IBDV)后,其法氏囊显微和超微结构的动态变化。光镜观察表明,在感染早期,淋巴滤泡髓质部的淋巴细胞发生坏死,间质轻度水肿。感染后4d,淋巴滤泡皮质内的毛细血管呈一典型的出血带环绕髓质,髓质部的淋巴细胞多已坏死、崩解。继之,整个淋巴滤泡呈网络状或囊状空泡。感染6d以后,固有膜内的网状细胞和毛细血管大量增生,新的淋巴滤泡形成。电镜观察证明,在感染早期,淋巴细胞质内的内质网与核膜扩张,线粒体嵴紊乱或空泡化。继之,淋巴细胞核液化,细胞坏死、崩解。巨噬细胞和多核巨细胞大量出现,其胞浆内含有大量吞噬体和吞噬泡。  相似文献   

20.
为研究T淋巴细胞和B淋巴细胞在鸡食管扁桃体中的出现、迁移、组织定位分布以及数量变化规律等一系列发育过程,本研究通过免疫组织化学方法,应用CD3和IgA单克隆抗体,研究鸡食管扁桃体的组织结构发育过程和淋巴细胞的发育过程。结果显示,各时期T、B淋巴细胞主要分布在两个部位:隐窝固有层和皱襞固有层,尤其是在隐窝固有层中T、B淋巴细胞较多;随着日龄增长,食管扁桃体中T、B淋巴细胞数量逐渐增多,并在35日龄时达到稳定;许多粘液腺周围形成淋巴聚集物,并突入腺腔,粘液腺上皮转化为淋巴上皮;21日龄之后,B淋巴细胞以IgA+细胞为主,数量超过CD3+细胞。研究表明,随着年龄增长,鸡食管扁桃体的免疫功能逐渐增强,并在21日龄之前以细胞免疫为主,21日龄之后以IgA介导的粘膜免疫为主。  相似文献   

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