Antibody responses of turkeys experimentally exposed to Mycoplasma synoviae.

The antibody response of turkeys exposed to Mycoplasma synoviae intravenously and by way of air sacs was determined by tube agglutination, plate agglutination, hemagglutination-inhibition (HI), and gel diffusion precipitin tests. The results suggested that continued antigenic stimulation was lacking in most turkeys and that the response was due mostly to IgM-type immunoglobulin. Under those conditions, both types of agglutination tests were effective and were more sensitive indicators of exposure than the HI test. The gel diffusion precipitin test was not considered effective under the conditions of this study. HI activity occurred in serums of intravenously exposed turkeys within 4 days of exposure. The sensitivity of this activity to 2-mercaptoethanol treatment suggested that IgM was responsible.     

Cell-mediated and humoral immune response of chickens to Mycoplasma synoviae.

The leukocyte migration-inhibition test was employed to demonstrate the presence of cell-mediated immunity and to ascertain its relation to immunoglobulin production in Mycoplasma synoviae infection in chickens. With peripheral leukocytes and a preparation of M. synoviae used as antigen, good discrimination was obtained between naturally or experimentally infected birds and uninfected control birds. Only the infected groups showed significant inhibition. Positive migration inhibition values developed in the second week of infection, often before the appearance of hemagglutination-inhibition titers, and continued to accompany the production of immunoglobulins with some degree of correlation for at least 6 or 12 months.     

Serological responses of chickens to low challenge doses of Mycoplasma synoviae

Groups of eight chickens were challenged with 10-fold dilutions of one of two strains of Mycoplasma synoviae (MS); each challenge group contained two noninfected sentinels. Both strains were highly efficient in colonizing the respiratory tract with challenge doses as low as 76 and 24 color-changing units/bird. Infection spread rapidly (within 7 days) to sentinels, while uninfected control chickens separated from infected chickens by two empty pens remained uninfected for the 56-day experimental period. Although sentinels and birds challenged with the lowest doses had weaker or slightly slower antibody responses in some cases as measured by serum plate agglutination, enzyme-linked immunosorbent assay (ELISA), and hemagglutination inhibition (HI), they generally exhibited a typical antibody response. Agglutination reactions tended to be weak, but a high percentage of tests (generally >30% from day 14 postchallenge) were positive. ELISA results were variable, and in some cases reactor rates were low (generally <20%), even though the chickens were colonized in the upper respiratory tract. The HI test was reliable in detecting infected groups; usually >50% were positive from 14 days postchallenge. Mean HI titers were higher when using hemagglutination antigens prepared from the homologous MS strain as compared with antigen prepared from the heterologous strain or with standard antigen prepared from WVU 1853.     

The humoral immune response of chickens to Mycoplasma gallisepticum and Mycoplasma synoviae studied by immunoblotting

The humoral immune response over time of White Leghorn chickens experimentally infected with Mycoplasma gallisepticum or M. synoviae by an aerosol inoculation or a contact exposure were compared by immunoblotting. The response of chickens infected with M. gallisepticum were similar with respect to proteins recognized and intensity of response, regardless of mode of infection. On the other hand, chickens infected by aerosolization of M. synoviae responded to more proteins and with greater intensity than did M. synoviae contact-exposed birds. Chickens infected with M. gallisepticum responded with antibodies to over 20 proteins, while chickens infected with M. synoviae responded with antibodies to 12 proteins. Field sera from chickens naturally infected on commercial poultry farms with M. gallisepticum or M. synoviae were analyzed by immunoblotting and were found to react with a number of mycoplasma proteins. However, no correlation was seen when comparing intensity of immunoblot staining and hemagglutination-inhibition titer of the field sera. The experimental antisera were used to identify species-specific proteins of M. gallisepticum and M. synoviae. Six immunogenic species-specific proteins of M. gallisepticum with relative molecular masses of 82 (p82), 65-63 (p64), 56 (p56), 35 (p35), 26 (p26), and 24 (p24) kilodaltons (kDa) were identified. Two species-specific proteins of M. synoviae with relative molecular masses of 53 (p53) and 22 (p22) kDa were identified. Additionally, a highly immunogenic 41 (p41) kDa protein of M. synoviae was identified. Species-specific proteins identified in these mycoplasmas and the 41 kDa protein of M. synoviae were purified by preparative SDS-PAGE in amounts sufficient for further characterization and for use in serodiagnostic tests.     

鸡滑液囊支原体的分离和鉴定研究

从河南某肉种鸡场疑似鸡滑液囊支原体感染的病鸡跗关节样品进行病原的分离与鉴定.分离菌经瑞氏染色,在油镜下呈球形或椭圆形.在固体培养基上表现为细小、光滑、致密的小菌落,菌落形态为“煎蛋状”.L型细菌鉴定发现菌体仍保持原有形态.菌体能够吸附红细胞,分解葡萄糖,但不能分解精氨酸和尿素,还可致SPF鸡胚死亡,说明该分离菌为支原体.进一步的血清学试验结果表明,该分离菌为鸡滑液囊支原体,而不是鸡毒支原体.根据已发表的鸡滑液囊支原体血凝素基因序列vlhA设计合成一对引物,经PCR扩增,该菌体能够扩增出鸡滑液囊支原体(773 bp)的特异性片段.人工感染试验结果显示,SPF鸡能够复制出自然病例.     

Isolation of Mycoplasma synoviae from infectious synovitis of chickens

This report describes the first isolations of Mycoplasma synoviae from the synovial sheaths and joints of commercial chickens affected with synovitis in Australia. Over 4 years 3 separate outbreaks were investigated in which up to 20% of birds exhibited clinical signs of poor growth and "hot foot" syndrome (swollen inflamed footpads). Once an outbreak occurred, chronic infection of the farm usually ensued. Grossly the hocks and footpads were swollen by a purulent exudate and associated inflammatory changes with histological features of a severe acute synovitis. Seroconversion of the flocks occurred at the time of the development of lesions. M. synoviae specific antibodies were demonstrated by ELISA in the joint fluid of affected birds. It is concluded that the cases described are similar to avian infectious synovitis syndrome caused by M. synoviae previously described overseas.     

7株鸡滑液囊支原体四川分离株全基因组分析

旨在了解滑液囊支原体(Mycoplasma synoviae,MS)遗传多样性,本研究对7株MS四川分离株进行全基因组测序及生物信息学分析.采用Illumina HiSeq平台和PE文库结合方式全基因组测序,运用各数据库注释,用MEGAX软件将7株MS与NCBI收录的8株MS全基因比较.结果 显示,分离自同一鸡场的4株...     

Evaluation of innate immune responses in bovine forestomachs

Previous studies had indicated an active role of bovine forestomachs in the response to alimentary disorders as well as to inflammatory and infectious processes in both the gastro-intestinal (GI) tract and elsewhere. We investigated the potential of bovine forestomachs to receive, elaborate and produce signals and mediators of the innate immune response. Indeed, we detected the expression of Toll IL-1R8/single Ig IL-1-related receptor (TIR8/SIGIRR) and other receptors and cytokines, such as Toll-like receptor (TLR)4, interleukin (IL)-1β, IL-10 and Caspase-1 in the forestomach walls of healthy cows. Their presence suggests an active role of forestomachs in inflammatory disorders of the GI tract and other body compartments. Moreover, interferon (IFN)-γ was revealed in ruminal content. We confirmed and further characterized the presence of leukocytes in the rumen fluids. In particular, T-, B-lymphocytes and myeloid lineage cells were detected in the ruminal content of both rumen-fistulated heifers and diseased cows. An acidogenic diet based on daily supplements of maize was shown to inhibit leukocyte accumulation, as opposed to a control, hay-based diet, with or without a soy flour (protein) supplement. On the whole, results indicate that bovine forestomachs can receive and elaborate signals for the immune cells infiltrating the rumen content or other organs. Forestomachs can thus participate in a cross-talk with the lymphoid tissues in the oral cavity and promote regulatory actions at both regional and systemic levels; these might include the control of dry matter intake as a function of fundamental metabolic requirements of ruminants.     

Experimentally induced synovitis of chickens with Mycoplasma synoviae: effects of dexamethasone treatment.

Specific - pathogen - free chickens were inoculated in the right tibiometatarsal joint with a synovitis-derived Mycoplasma synoviae strain before or during dexamethasone treatment. Development of synovitis in chickens inoculated during the drug treatment was apparently delayed in comparison with development of synovitis in non-treated chickens. Severity of clinical synovitis in chickens inoculated before the drug was given was apparently less than that in chickens not treated or in chickens treated with dexamethasone. Histopathologic changes in the early stage of the infection (1 to 2 weeks) were not modified by dexamethasone treatment, although those changes in the succeeding stage (6 to 7 weeks) were greatly lessened. A relationship was observed between the dosage of dexamethasone and the severity of synovitis, as well as the kinds of cells that infiltrated into the joint lesions. Although serum antibody titers in chickens treated with an excessive dose of dexamethasone were markedly lower, clinical, bacteriologic, and histopathologic observations in chickens treated with dexamethasone were similar to those previously found in surgically thymectomized chickens. These results may support the theory that multiple synovitis of chickens caused by M synoviae infection develops mainly because of an immune response, especially by thymus-dependent functions.     

鸡滑液囊支原体的流行调查及不同地区分离株药物敏感性分析

为了解近年来鸡滑液囊支原体感染的流行情况,自2015年1月-2017年12月,对广东、广西、江苏、浙江、福建等地10个不同地区养殖场的感染情况进行调查分析。结果显示,该病在调查的10个不同地区均有发生,感染鸡群多见于l～4月龄,平均感染日龄为60日龄;8个不同品种鸡的平均感染率为8.89%,平均死亡率为2.16%。感染率和死亡率均存在品种差异,其中817肉杂鸡及清远麻鸡的感染死亡率最高。从157份疑似鸡滑液囊支原体感染鸡的病料中分离到96株田间流行株,各地区随机取1株进行10种常用抗菌药物的敏感性测定。结果表明,10株临床分离株均对泰妙菌素、泰万菌素、泰乐菌素及多西环素较为敏感,对金霉素、庆大霉素等的敏感性显著下降且出现不同程度的耐受性,对盐酸环丙沙星、沙拉沙星敏感性较差,此结果可为临床合理用药提供参考。     

In vitro susceptibilities to fluoroquinolones in current and archived Mycoplasma gallisepticum and Mycoplasma synoviae isolates from meat-type turkeys

Monitoring of susceptibility to antibiotics in field isolates of pathogenic avian mycoplasmas is important for appropriate choice of treatment. Our study compared in vitro susceptibility to enrofloxacin and difloxacin in recent (2005-2006) isolates of Mycoplasma gallisepticum and Mycoplasma synoviae from meat-type turkey flocks with archived (1997-2003) isolates and reference strains. Comparison of minimal inhibitory concentration (MIC) values determined by microtest, agar dilution and commercial Etest showed good agreement, but underscored the need for standardized methods for testing. Notably, while the commercial Etest was convenient and accurate for determining MICs for enrofloxacin in the range 0.002-0.094mug/ml, the endpoint of inhibition for M. gallisepticum and M. synoviae strains with MIC values >/=1.0mug/ml could not be determined. A decrease in susceptibility to both fluoroquinolones was detected in archived strains but to a greater degree in recent isolates, most of which had MICs above the NCCLS susceptibility breakpoint for these antibiotics (相似文献   

1株鸡滑液囊支原体的分离鉴定与全基因组分析

鸡滑液囊支原体（Mycoplasma synoviae,MS）能引起家禽呼吸道疾病、传染性滑膜炎、蛋壳顶端异常及生长迟缓等,给全球养禽业带来巨大的经济损失。然而不同国家和地区MS的耐药性和致病性存在差异,因此本研究旨在挖掘福建MS菌株的特征。作者采集福建省疑似患MS的病鸡关节腔内容物,对菌株进行分离鉴定,并利用三代联合二代测序技术对其进行全基因组测序。结果显示,该分离株病原特性稳定,已保藏至中国典型培养物保藏中心,保藏编号为CCTCC No.：M 2021210,并将其命名为MS-FJ01。MS-FJ01基因组全长为795 381 bp,GC含量为28.39%;预测编码基因数为704个,占整个基因组的90.48%;并在COG、GO和KEGG数据库分别注释到476、382、425个基因。通过各数据库的分析,注释了40个耐药相关基因,4个碳水化合物相关酶基因,136个病原与宿主互作相关基因,47个毒力因子相关基因,106个膜转运蛋白相关基因,25个限制修饰相关基因。通过与MS HN01和MS 5-9基因组进一步比较发现,MS-FJ01与这两个中国菌株均存在良好的共线性关系,且与MS 5-9的亲缘关系更近。本研究阐明了福建MS菌株的基因组结构、通过相关数据库的分析,预测和注释了其基因的功能,为深入研究MS提供参考依据。     

Fowl adenoviruse-4 infection induces strong innate immune responses in chicken

Fowl adenovirus (FAdV), as the causative agent of hepatitis-hydropericardium syndrome (HHS), poses a significant threat to the poultry industry in China in recent years. In this study, we investigated the immunopathogenesis of a FAdV-4 strain HN/151025 in 60-day-old chickens. The virus was highly virulent in chickens, with a broader tissue tropism in chickens, causing 60 % mortality. Postmortem findings of dead chickens showed mild HHS and liver degeneration and necrosis. Importantly, FAdV-4 infection induced significant upregulation of genes encoding most toll-like receptors, some cytokines (interleukin-1β, 2, 6, 8, and 18, and interferon-γ), most of avian β-defensins, myeloid differentiation primary response protein 88, p38 mitogen-activated protein kinases, and inducible nitric oxide synthase, in tissues of infected chicken, especially in spleen and bursa of Fabricius. There was also a significant positive correlation between FAdV-4 genome load and the mRNA expression levels of most of these factors in specific infected tissues. The results indicated the potential role of these proteins in host immune response against FAdV-4 infection. However, overexpression of these proteins might contribute to tissue damage of FAdV-4 infected chickens, and eventually lead to chicken death.     

Evaluation of local and systemic immune responses induced by intramuscular injection of a Mycoplasma hyopneumoniae bacterin to pigs

OBJECTIVE: To evaluate immune responses induced by administration of Mycoplasma hyopneumoniae bacterin to pigs. Animals-60 healthy 7- to 10-day-old cross-bred boars. PROCEDURE: Pigs were assigned to 1 of 4 pig groups (15 pigs/group): vaccinated, challenged; vaccinated, nonchallenged; nonvaccinated, challenged; nonvaccinated, nonchallenged. Vaccinated pigs received IM injections of a mycoplasma bacterin on days 0 and 14, whereas nonvaccinated pigs received saline (0.9% NaCl) solution. Pigs in the challenged groups were inoculated intratracheally with M hyopneumoniae on day 42. Pigs were euthanatized and necropsied 41, 44, 48, and 70 days after the first vaccination, and proportion of lung surface with pneumonic lesions was determined. Percentage of lymphocyte subpopulations and number of interferon-gamma (IFN-gamma) secreting lymphocytes in blood and tissues, cytokine and antibody concentrations in bronchoalveolar lavage (BAL) fluid, and serum antibody concentrations were determined. RESULTS: Vaccination against and infection with M hyopneumoniae induced a local mucosal immune response in the respiratory tract of pigs. Proportion of lung surface with pneumonic lesions in vaccinated challenged pigs was reduced on day 70, compared with nonvaccinated challenged pigs. Vaccination stimulated the production of M hyopneumoniae-specific IFN-gamma secreting blood lymphocytes. Tumor necrosis factor-alpha concentration in BAL fluid on day 70 was increased in nonvaccinated challenged pigs, compared with vaccinated challenged pigs. CONCLUSIONS AND CLINICAL RELEVANCE: Vaccination against M hyopneumoniae induced local, mucosal, humoral, and cellular immune responses. Moreover, vaccination reduced the severity of lung lesions in challenged pigs, suggesting that mucosal antibodies, mediation of the inflammatory response, and cell-mediated immune responses are important for control of mycoplasmal pneumonia in pigs.     

Isolation of Mycoplasma synoviae from the brains of commercial meat turkeys with meningeal vasculitis

Mycoplasma synoviae (MS) was isolated from the brains of 22-week-old commercial meat turkeys displaying severe synovitis and infrequent central nervous system signs. Histological examination of the brains revealed mild-to-severe meningeal vasculitis. The vasculitis ranged from fibrinoid necrosis with little inflammation to a marked infiltration of lymphocytes and plasma cells disrupting the architecture of the vessel wall, accumulating as perivascular cuffs, and involving surrounding meninges. Occasional arteries were undergoing thrombosis. Similar lesions were occasionally seen in renal, synovial, and splenic vessels. MS isolates from the brain, trachea, and joint showed similar protein-banding patterns by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. However, the protein profile differed markedly from the standard MS reference strain, WVU 1853. This is the first known field case of MS isolation from the brains of turkeys.     

Humoral and cellular immune responses of pigs inoculated with Mycoplasma hyopneumoniae

Cellular and humoral immune responses of pigs inoculated with Mycoplasma hyopneumoniae were investigated at postinoculation weeks (PIW) 2, 4, and 6. The response of blood lymphocytes (BL) and bronchial lymph node lymphocytes (LNL) to stimulation by M hyopneumoniae antigens was evaluated by a lymphocyte-stimulation test. Specific antibodies in serum and lung washing samples were assayed by ELISA. Immunoglobulin-positive cells in lungs and bronchial lymph nodes were identified by indirect fluorescent antibody test, using isotype-specific monoclonal antibodies. At PIW 0 to 6, BL from control and M hyopneumoniae-inoculated pigs were stimulated by M hyopneumoniae cells; however, BL from inoculated pigs generally had higher stimulation indices, especially at PIW 6. The response of LNL was influenced by previous exposure to M hyopneumoniae, as indicated by higher stimulation indices (P less than 0.01) of LNL from inoculated pigs killed at PIW 2 and 6. Specific ELISA antibodies to M hyopneumoniae in lung washings from inoculated pigs consisted mainly of IgG and IgA isotypes. Examination of lung sections by indirect immunofluorescence revealed that cells producing IgM and IgA were in controls as well as M hyopneumoniae-inoculated pigs, but IgG-positive cells were only in lungs of inoculated pigs. Resolution of pneumonia appeared to correlate with development of increased sensitization of BL, as well as development of marked increases in immunoglobulins, particularly IgG in lung washings at PIW 6.     

川西地区鸡滑液囊支原体分离株的部分生物学特性及其VlhA基因遗传进化分析

为了解鸡滑液囊支原体(MS)在川西地区的感染情况,本研究采集15个肉鸡场疑似MS感染的病鸡咽拭子、跗关节和胸部滑液囊样本共75份,对经PCR检测为阳性的样本进行MS分离,并对分离株的主要生物学特性进行研究,以及对分离株的VlhA基因进行遗传进化分析。结果显示,75份样本MS PCR阳性检出率为41.33%(31/75),11个鸡场感染该病,场阳性率为73.33%(11/15);但仅从其中3个鸡场分离到9株MS,分离株菌落与菌体形态与已知MS培养特性相符,各分离株培养浓度为10~4CCU/mL^10~6CCU/mL,分离株以5×10~5CCU接种7日龄SPF鸡胚,鸡胚于接种后7 d^9 d死亡,且分离回收到接种菌株;9株MS分离株VlhA基因的同源性为86.1%~99.9%,与参考株同源性为86.2%~95.4%,其中分离自同一鸡场的7株MS VlhA基因同源性为96.4%~99.9%;分离株VlhA基因遗传进化分析显示,其中分离自两个不同鸡场的两株MS与国内流行株的亲缘关系最近,而分离自另一鸡场的7株MS与中东地区分离的3株MS亲缘关系较近,表明MS在川西地区肉鸡场呈高感染率,MS VlhA基因变异较大。本研究为川西地区MS的进一步研究提供了基础材料和科学依据。     

鸡滑液囊支原体不同地区分离株对常用抗菌药物的敏感性试验

为调查不同地区鸡滑液囊支原体的耐药情况,从河南、江苏、安徽、河北和广东五省204份疑似鸡滑液囊支原体感染鸡的病料中分离到20株鸡滑液囊支原体,每省随机取1株进行了12种常用抗菌药物的敏感性测定。结果表明,5株鸡滑液囊支原体均对泰乐菌素较为敏感,而对恩诺沙星、氧氟沙星、盐酸环丙沙星具有不同程度的耐受性。本实验可为临床合理用药提供参考。     

Systemic innate immune responses following intrapulmonary delivery of CpG oligodeoxynucleotides in sheep

Mucosal delivery of CpG oligodeoxynucleotide (ODN) in mice has been shown to induce potent innate immunostimulatory responses and protection against infection. We evaluated the efficacy of CpG ODN in stimulating systemic innate immune responses in sheep following delivery to the pulmonary mucosa. Intrapulmonary (IPM) administration of B-Class CpG ODN in saline induced transient systemic responses which included increased rectal temperatures, elevated serum 2'5'-A synthetase and haptoglobin concentrations. The ODN dose required to induce detectable systemic responses following IPM delivery could be reduced by approximately 80% if the CpG ODN was administered in 30% emulsigen instead of saline. Intrapulmonary B-Class CpG ODN formulated in 30% emulsigen produced similar effects when compared to those seen following SC injection. These responses were CpG ODN-specific since control GpC ODN did not induce any detectable response. Intrapulmonary administration of both B-Class and the newly described C-Class CpG ODN produced similar effects indicating that both classes of CpG ODN were comparably effective in stimulating innate immune system following mucosal delivery. Administration of CpG ODN directly into the lungs or delivery of CpG ODN via an intratracheal (IT) infusion also produced similar systemic responses. These observations support the conclusion that mucosal delivery of CpG ODN is an effective route for induction of systemic acute phase responses and antiviral effector molecules in large animals, and may be helpful in controlling systemic infections.     

脂多糖诱导奶牛乳腺上皮细胞先天性免疫反应

采取荷斯坦奶牛乳腺,进行体外分离培养,并纯化细胞。用不同质量浓度(0、1、10、100mg/L)的脂多糖刺激乳腺上皮细胞,采用MTT法检测脂多糖对细胞增殖的影响,半定量PCR检测10mg/L的LPS对乳腺上皮细胞TLR4、TLR2、CD14、MD-2四个基因在不同时间(0、2、6h)mRNA表达水平的差异。结果表明,高剂量(100mg/L)的LPS对乳腺上皮细胞的增殖产生明显影响;LPS刺激乳腺上皮细胞后,导致TLR4、CD14、MD-2mRNA表达迅速升高,而TLR2mRNA弱表达。说明TLR4、CD14、MD-2参与LPS的识别,同时也说明脂多糖刺激乳腺上皮细胞后,乳腺上皮细胞能够产生先天性免疫反应。