Inflammation-induced changes in serum modulate chicken macrophage function

Inflammation-induced changes in serum protein profiles and the effects of such serum on a chicken macrophage cell line HD11 were studied to find whether the changes in serum affect cellular immunity. Four-week-old male broiler chickens were injected subcutaneously with either olive oil or 50% croton oil mixed in olive oil to induce inflammation. The birds were bled at 48 h after injection, and serum protein profiles were compared using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and densitometric evaluation. At 48 h post-injection the serum from croton oil-injected birds showed distinct changes in protein profiles characterized by a selective increase or decrease in levels of several serum proteins. The protein bands which showed increases had relative molecular weights (Mr) corresponding to 65 kilo Daltons (kD), 42 kD, and two or more proteins with Mr≥200 kD. The levels of serum albumin (49 kD), and a 56 kD protein were reduced in croton oil-injected birds. The modulating effects of such serum on HD11 cells were studied using bacterial lipopolysaccharide (LPS) or phorbol myristate acetate (PMA) induced functional activation of these cells. The LPS-induced interleukin-6 (IL-6) production by HD11 cells was not affected by the presence of either olive oil-treated control or croton oil-treated inflammatory serum but nitrite production was enhanced by the inflammatory serum. Similarly, inflammatory serum also enhanced PMA-induced respiratory burst measured using dichlorofluorescein diacetate (DCF-DA) oxidation mediated by reactive oxygen intermediates. These results suggest that inflammatory serum can modulate macrophage function by influencing the production of reactive oxygen and nitrogen species which could affect their phagocytic and bactericidal activities.     

鸡热应激与热应激蛋白的作用机理研究

高温导致畜禽热应激问题的危害正日益突出并倍受关注。针对这些问题本刊推出“热应激专栏”,目的是为缓解夏季普遍存在的畜禽热应激提供理论和技术支持,使从业者能通过一些技术手段来规避热应激带来的损失。由于时间的仓促,本期组织的稿件内容覆盖面不是很全,但是以后会陆续推出有关内容,希望大家能继续关注。同时我们也希望专家、学者能踊跃地发表真知灼见与广大读者分享,把热应激理论、防制调控推到一个更高的阶段。     

四君子汤对小鼠腹腔巨噬细胞吞噬功能的影响

四君子汤是补益脾胃的代表方剂,主要根据"脾胃中州""脾虚易生湿""湿重易伤脾"的中医理论组方遣药,临床实践中常用作治疗脾虚证和各种虚证.     

DON暴露对雏鸡免疫功能的影响

本试验旨在通过脱氧雪腐镰刀菌烯醇(deoxynivalenol,DON)暴露雏鸡体内毒理试验,根据免疫器官指数与病理剖检、血清抗体效价和免疫球蛋白水平的变化,研究DON对雏鸡免疫功能的影响。选取临床检查健康的120只1日龄海兰蛋公鸡,按单因素试验设计,随机分成4组,每组30只。试验雏鸡饲喂相同的全价日粮,从8日龄开始,低剂量组、中剂量组和高剂量组分别按采食量含DON 0.27,1.68,12.21mg/kg的剂量灌胃染毒,对照组灌服等量的生理盐水,每隔7d染毒1次,共染毒5次。试验期为36d。每次染毒前1d,每组随机抽取10只鸡,翅下静脉采血,分离血清,用于检测免疫球蛋白水平和抗体效价。试验结束时,每组随机屠宰20只,取胸腺、法氏囊和脾脏,计算免疫器官指数,并观察病理变化。结果显示:与对照组相比,低、中剂量组血清免疫球蛋白水平呈现降低的趋势,但差异不显著(P0.05),高剂量组显著降低(P0.05);各试验组血清抗体效均价差异不显著(P0.05);低、中剂量组脾脏指数显著升高(P0.05),中剂量组胸腺指数显著降低(P0.05),高剂量组脾脏和胸腺指数均显著降低(P0.05)。病理切片观察发现,各试验组脾脏和法氏囊均出现不同程度的水肿,胸腺出现不同程度充血、淤血,高剂量组伴有大量浆液渗出。结果表明:DON暴露能影响免疫器官指数和免疫球蛋白水平,并损害免疫器官,从而降低雏鸡的免疫功能。     

Organic barn dust extract exposure impairs porcine macrophage function in vitro: Implications for respiratory health

Respiratory diseases are responsible for a significant amount of animal morbidity and mortality in the swine industry, including the majority of nursery and grower/finisher deaths. Innate immunity, including the maintenance of lung macrophage health and function, is an important defense mechanism against respiratory pathogens and their associated losses. Chronic exposure of swine industry workers to airborne barn dust results in significant predisposition to airway diseases and impairment of alveolar macrophage (AM?) function. Because of their importance in maintaining normal respiratory function, this study was designed to evaluate the impact of barn dust on swine macrophages. As measures of macrophage function, we evaluated the activation of NF-κB, cytokine production, cell surface marker expression and the phagocytic and antibacterial capabilities of porcine macrophages after in vitro exposure to an organic swine barn dust extract (ODE). ODE treatment induced AM? secretion of both pro- and anti-inflammatory cytokines, suggesting a complex activation profile. Additionally, ODE induced expression of genes (TLR2, NOD2) involved in sensing Gram-positive bacteria, a major component of barn dust. ODE exposure also enhanced the expression of several cell surface markers of activation, including a receptor for the porcine reproductive and respiratory syndrome virus. Moreover, two key functions of AM?, phagocytosis and bacterial killing, were impaired after exposure to ODE. Treatment with ODE for the first 72 h of differentiation also inhibited the ability of monocyte-derived macrophages to translocate NF-κB to the nucleus following endotoxin stimulation. Taken together, these results demonstrate, for the first time, that organic dust extract exposure negatively affects pig macrophage activation and function, potentially enhancing host susceptibility to a variety of respiratory infections.     

复方中药注射液对小鼠腹腔巨噬细胞吞噬能力的影响

随着人们健康意识的加强．畜产品的安全问题越来越受到广大消费者的普遍关注。大量的生产试验证明，中兽药在畜禽饲养中具有化学兽药无法替代的优势，它本身具有天然性、多功能性、微毒副作用、无抗药性等特点。基于此笔者等研究开发了一种复方中药注射液，现将其对小鼠腹腔巨噬细胞吞噬能力的影响作如下报告。     

穿心莲内酯提高异嗜性粒细胞吞噬和杀伤鸡大肠杆菌O78功能的体外试验

模拟大肠杆菌O78在血液中被鸡异嗜性粒细胞吞噬杀伤的过程,利用激光共聚焦和涂板茵落计数的方法研究中药单体成分穿心莲内酯对异嗜性粒细胞吞噬杀伤大肠杆菌O78活性的影响.结果显示,穿心莲内酯质量浓度为1 mg/L时有极显著的提高异嗜性粒细胞吞噬大肠杆菌O78的作用(P＜0.01),并且在异嗜性粒细胞发挥杀伤作用的12h后有极显著的增强其杀伤作用的功效(P＜0.01).结果表明,穿心莲内酯能够提高异嗜性粒细胞吞噬、杀伤大肠杆菌O78的活性,从而起到增强机体抗病能力,提高机体免疫力的作用.     

Morphologic changes in chicken cells after in vitro exposure to Mycoplasma gallisepticum

Mycoplasma gallisepticum (MG) was used to expose chicken peripheral blood lymphocytes (PBLs), red blood cells (RBCs), heterophils, and chicken tumor cells (MSB-1 and HD-11 cells). Incubation of PBLs with MG for 3 hr resulted in extensive clumping of lymphocytes. Incubation of the MSB-1 cells with MG also caused clumping of the cells, with many of the cells showing perforations and others showing capping of the surface projections. Incubation of RBCs with MG resulted in an altered cell surface morphology, a decrease in cell size, and perforation. There were no discernible changes on the surface of the heterophils and the HD-11 cells. However, the HD-11 cells appeared to have a decreased ability to attach to the surface of the plastic and to have a decreased ability to respond to chemoattractant fMLP after 24 hr of incubation. These results suggest that, under the conditions used, MG caused certain damage to peripheral blood cells and a significant decrease in chemotactic response in the HD-11 cells.     

Sequential morphological changes in chicken erythrocytes after in vivo and in vitro exposure to phenylhydrazine-hydrochloride

In acute haemolytic anaemia of chickens, induced with the oxidant chemical phenylhydrazine-hydrochloride, maximum degenerative changes in the in vivo exposed erythrocytes occurred on day 3 after injection. Microspherocytic transformation, dumb-bell shaped red blood cells and foamy squashed nuclei predominated. Heinz body formation was the cytoplasmic hallmark of the haemolytic anaemia. Marked reticulocytosis on day 5 indicated spontaneous regeneration. In vitro exposure to the chemical agent evoked similar morphological aberrations/Heinz bodies, microspherocytic transformation and nuclear degeneration. These were induced much earlier, presumably because of the absence of a protective internal milieu. Nevertheless, a basic similarity in morphology was evident. The in vitro test system might be suitable for screening oxidant chemicals and drugs.     

Impairment of macrophage function in Mongolian gerbils.

Chemiluminescence studies on superoxide generation by phagosomes using opsonized zymosan showed the highest fluorescence in murine splenic macrophages among four different kinds of splenic or peritoneal macrophages from mice or gerbils. Murine splenic macrophages phagocytized two to three times more latex particles than gerbil splenic macrophages, but peritoneal macrophages did not show a significant difference in phagocytic activity between mice and gerbils. Phagocytosis by macrophages was determined by a technique based on measurement of the release of hydrogen peroxide and myeloperoxidase from phagosomes using microspheres conjugated with 3-(p-hydroxyphenyl) propionic acid (HPPA-MS). HPPA is a substrate of lysosomal myeloperoxidase. The fluorescence of HPPA-HPPA-MS produced by phagocytized HPPA-MS was measured with an immunoreaction analysis system (IMRAS), and the enzyme activities of the four different kinds of peritoneal or splenic macrophages from mice and gerbils were compared. All four kinds of macrophages produced HPPA-HPPA-MS in their phagosomes during phagocytosis and murine splenic macrophages showed the highest level of enzyme activity.     

Modulation of bovine mammary neutrophil function during the periparturient period following in vitro exposure to recombinant bovine interferon gamma

Effects of recombinant bovine interferon (rBoIFN) gamma on mammary gland neutrophil activity during the periparturient period were studied. Bovine mammary gland neutrophils were isolated and incubated in mammary gland secretions obtained from Holstein-Friesian cattle during the last 2 weeks of gestation. Cell functions were evaluated following treatment with 10 U, 100 U, and 1000 U of rBoIFN-gamma. Bacterial phagocytosis, bactericidal activity and chemiluminescence were significantly lower for neutrophils incubated in mammary gland secretions when compared with control neutrophils incubated in Hank's balanced salt solution. Treatment of mammary neutrophils with rBoIFN-gamma reversed the suppressive effects of mammary secretions resulting in higher chemiluminescent activity and significantly more bacterial phagocytosis and bactericidal activity when compared with untreated controls. Results from these preliminary in vitro data suggest that rBoIFN-gamma therapy may modulate mammary gland neutrophil functions in vivo and possibly facilitate the rapid clearance of mastitis-causing pathogens mammary glands during the periparturient period.     

Evaluation of differentially expressed proteins following serum exposure in avian pathogenic Escherichia coli

Colibacillosis, caused by avian pathogenic Escherichia coli (APEC), is an extraintestinal disease that causes great economic loss to the poultry industry each year. APEC must overcome host defenses, such as immune system components found in serum, in order to establish infection; however, the mechanism of such serum resistance has been elusive. In the present study, a proteomic approach was used to evaluate APEC proteins that were differentially expressed after exposure to chicken serum to identify specific proteins that may be involved in serum resistance of APEC isolates. Proteins were isolated and separated by two-dimensional (2D) gel electrophoresis, and 10 protein spots corresponding to differentially expressed proteins were chosen for sequencing using electrospray ionization tandem mass spectrometry. Eight proteins were identified among the spots, some of which have previously been associated with the virulence of E. coli. Significantly, an outer-membrane protein previously associated with serum resistance, OmpA, was among those proteins identified, further indicating that differential regulation of this protein may be involved in serum resistance. This study opens the door to future research using a proteomic approach to identify the key players in serum resistance of APEC.     

Induction of chicken interferon by avian infectious bronchitis virus.

The ability of nine strains of avian infectious bronchitis virus (IBV) to induce chicken interferon has been investigated using Semliki Forest virus for the tests. The Beaudette, H120 and Connecticut 46 strains induced interferon in the allantoic fluids of embryonated hens' eggs, the highest titre (1 : 30) being associated with Beaudette; but these as well as the Massachusetts M-41 and H52 strains failed to yield interferon in primary monolayer cultures of chick kidney cells as did all nine strains in organ cultures of chick embryo trachea. None of six strains of IBV investigated was susceptible to the inhibitory effects of chicken interferon.     

Induction of acid-stable canine interferon in vivo and in vitro.

Dogs were able to produce only small quantities of circulating interferon after intraperitonal injection of Newcastle disease virus or polyinosinic-polycytidylic acid. Similarly, canine cell cultures produced very low concentrations of interferon in response to Newcastle disease virus or polyinosinic-polycytidylic acid and no detectable concentrations of interferon in response to pyran copolymer or tilorone hydrochloride. The antiviral substance met the physiochemical characteristics classically associated with interferon.     

鸡热应激的危害及防治措施

我国大部分地区夏季炎热期达3个月之久，长江以南地区高温持续时间更长，严重影响鸡群的生长和生产性能，导致鸡群采食量减少，体重下降，肉仔鸡生长缓慢，蛋鸡产蛋率下降，给养鸡业带来重大经济损失。因此，在夏季必须重视鸡舍的防暑降温，加强饲养管理，并通过某些营养素的调节来改善热应激造成的鸡群生产性能的下降，确保鸡群能安全渡夏，从而提高鸡群在热应激状态下的经济效益。     

鸡的体温与热调节

鸡有独特的体温与热调节机制和规律,这些机制和规律是由其独特的解剖生理学和行为特点所决定的。1鸡体温调节机能发育与体温变化规律1.1鸡体温与热调节机能发育鸡的体温与热调节机能发育较早,体温恒定调节中枢发育是从胚胎时期就开始,出壳后虽不完善,但可以由绒毛覆盖来补充。在孵化期,鸡胚的温度超过37℃,刚出壳的雏鸡只有30℃,以后升高,在最适宜环境温度条件下的白来航鸡出壳12h体温39～40℃,10日龄40.3℃,20日龄达到40.9℃,体温调节机能发育逐步完善,30日龄41℃,成年鸡体温平均41.5℃。出壳雏鸡绒毛潮湿,蒸发散热量大,使刚出壳雏鸡体温下…     

Induction of the 68 kDa major heat-shock protein in different Theileria annulata- and virus-transformed bovine lymphoblastoid cell lines.

Expression of the major inducible heat-shock protein of 68 kDa (hsp68) has been analyzed in peripheral blood mononuclear cells (PBMC) from cattle and in six Theileria annulata- and two bovine leukemia virus-transformed bovine lymphoblastoid cell lines (BoLCL). By metabolic labeling, hsp68 could be detected in PBMC and BoLCL only after heat-shock, but not under normal culture conditions. Immunoblot analysis with an hsp68 reactive monoclonal antibody similarly revealed a strong hsp68 response after heat-shock in BoLCL, and no hsp68 expression under normal culture conditions. Normally kept PBMC, however, were weakly positive with the antibody. The data are discussed with respect to the constitutive expression of hsp68 seen in several other cell lines.