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31.
Recent studies have shown that tumour cells express tumour necrosis factor-inducible gene 6 (TSG-6) and its protein, which is known to play a key role in regulating excessive immune responses and proliferation and growth of mesenchymal stem cells (MSCs). It has not been confirmed whether the inhibition of TSG-6 for tumour cells can suppress tumour cell growth and regulate the activation of immune cells in the tumour microenvironment (TME). TSG-6-specific small interfering RNA was transfected into canine and human breast cancer cells (CIPp, CIPm and BT-20). TSG-6-down-regulated (siTSG-6) cells showed decreased cell proliferation, migration, and invasion abilities. Decreased mRNA expressions of NF-κB, STAT3 and Sox2, confirming that TSG-6 is an upper factor governing tumour growth and metastasis. Notably, siTSG-6 cells showed significantly decreased expression levels of CD44 and PD-L1. Direct and indirect co-culture of canine peripheral blood mononuclear cells (cPBMCs) and the siTSG-6 cells showed significant activation in M1 type macrophages and cytotoxic T cells. They also showed a tendency to decrease in the expression of CTLA-4 and increase in the expression of PD-1. In conclusion, this study suggests that the down-regulation of TSG-6 in breast cancer cells could not only suppress tumour growth and metastasis, and but also regulate TME. Since modulation of immune checkpoint proteins occurs in both tumour cells and immune cells, inhibiting TSG-6 and its protein within the TME could be novel therapeutic target for anticancer treatment.  相似文献   
32.
Mannose-binding lectin (MBL) is a key protein in innate immunity. MBL binds to carbohydrates on the surface of pathogens, where it initiates complement activation via the lectin-dependent pathway or facilitates opsonophagocytosis. In vitro studies have shown that human MBL is able to bind to Salmonella, but knowledge in relation to chicken MBL and Salmonella is lacking. In order to study this relation day-old chickens from two selected lines L10H and L10L, differing in MBL serum concentration, were either orally infected with S. Infantis (S.123443) or kept as non-infected controls. The differences between healthy L10H and L10L chicken sublines were more profound than differences caused by the S. Infantis infection. The average daily body weight was higher for L10H than for L10L, regardless of infection, indicating beneficial effects of MBL selection on growth. Salmonella was detected in cloacal swabs and the number of Salmonella positive chickens during the experiment was significantly higher in L10L than L10H, indicating that MBL may affect the magnitude of Salmonella colonisation in day-old chickens. MBL expression was determined in ceca tissue by real-time RT-PCR. L10H chickens showed a significantly higher relative expression than L10L at days 1 and 41 pi, regardless of infection. Finally, flow cytometric analysis of whole blood from infected chickens showed that L10H had a significantly higher count of all assessed leucocyte subsets on day 5 pi, and also a higher count of monocytes on day 12 pi than L10L. No difference was observed between infected and non-infected L10L chicken.  相似文献   
33.
Previously, we reported that ovarian hormones affect the immune response against E. coli isolated from the dogs affected with pyometra. In order to investigate mechanisms underlying the immune modulation, we examined the effects of ovarian hormones on the generation of dendritic cells (DCs), the most potent antigen presenting cell. DCs were differentiated from peripheral blood monocytes (PBMOs) using a cytokine cocktail. Both estrogen receptor and progesterone receptors were expressed by the PBMOs and immature DCs. When various ovarian hormones were added to the culture for the DC differentiation, progesterone significantly decreased the expression of DC maturation markers, such as CD1a, CD80 and CD86, on mature DCs. Conversely, the addition of estrogen to the cultures increased the expression of CD86, but not other maturation makers. Furthermore, DCs differentiated in the presence of progesterone did not stimulate allogeneic mononuclear cells in PB. Taken together, these results indicate that progesterone diminishes the maturation of DCs, leading to decreased immune responses against invading pathogens.  相似文献   
34.
本试验旨在研究苏氨酸和异亮氨酸对皖西白鹅屠宰性能、器官指数及肠道形态结构、消化酶活性、抗氧化和免疫指标的影响。选取30日龄体重相近的皖西白鹅180只,随机分为3组,每组3个重复,每个重复20只。对照组饲喂基础饲粮,苏氨酸组在基础饲粮中添加2.0 g/kg的L-苏氨酸,异亮氨酸组在基础饲粮中添加2.5 g/kg的L-异亮氨酸。试验期60 d。结果表明:1)各组之间90日龄屠宰性能和器官指数无显著差异(P>0.05)。2)异亮氨酸组60日龄十二指肠和空肠绒毛高度、隐窝深度显著或极显著高于对照组(P<0.05或P<0.01),苏氨酸组60日龄十二指肠、空肠和回肠隐窝深度及90日龄十二指肠和回肠绒毛高度显著或极显著高于对照组(P<0.05或P<0.01)。3)苏氨酸组和异亮氨酸组60、90日龄十二指肠胰蛋白酶活性极显著高于对照组(P<0.01),苏氨酸组60、90日龄十二指肠麦芽糖酶活性及90日龄空肠淀粉酶、乳糖酶活性显著或极显著高于对照组(P<0.05或P<0.01)。4)异亮氨酸组60日龄空肠总抗氧化能力显著高于对照组和苏氨酸组(P<0...  相似文献   
35.
This study investigated whether offspring from n‐3‐supplemented breeders have an enhanced performance and immune organ weight when fed a post‐hatch n‐3‐enriched diet in comparison with their control‐fed counterparts and the importance of timing of omega‐3 supplementation. Therefore, 480 Ross‐308 broiler breeder hens were fed one of four different diets (120/treatment). The control diet (CON) was a basal diet, rich in n‐6 fatty acids (FA). The three other diets were enriched in n‐3 FA, formulated to obtain a different EPA/DHA ratio of 1/1 (EPA = DHA), 1/2 (DHA) or 2/1 (EPA). At 33 weeks of age, eggs were incubated to obtain 1440 offspring. They were set up according to their maternal diet and sex in 48 pens of 30 chicks each (12 pens per maternal treatment: six male and six female). Half of the offspring were given a post‐hatch control diet, whereas to other half received an n‐3‐supplemented diet. Zootechnical performance was followed for starter, grower and finisher phase, and at the end of each phase two, chicks per pen were sacrificed to determine the weight of the immune organs. No interaction was found between maternal and post‐hatch n‐3 treatment for zootechnical performance. An interaction arose between the maternal and post‐hatch n‐3 supplementation for proportional bursa weight at day 1 and day 14 and proportional liver weight at day 14, but effects on immune organ weight were rather limited. Offspring post‐hatch n‐3 supplementation did not enhance maternal n‐3 supplementation.  相似文献   
36.
为了研究纯化浓缩的猪细小病毒灭活疫苗的免疫效果,应用微滤/超滤管式陶瓷膜分离系统对猪细小病毒细胞收获液进行纯化浓缩,使浓缩液病毒平均含量由10~(4.7)TCID_(50)/mL提高到10~(6.5)TCID_(50)/mL;将纯化浓缩的病毒液经检验合格后,进行甲醛灭活,与注射用矿物白油佐剂制成油包水灭活疫苗;按照猪细小病毒灭活疫苗的质量标准,对制备的灭活疫苗进行检验与免疫效果试验。结果显示:纯化浓缩的猪细小病毒液杂蛋白去除率平均达到71.6%左右;制备的三组灭活疫苗检验均合格;免疫至63 d时,免疫猪体内抗猪细小病毒抗体(HI)水平分别为:纯化浓缩的灭活疫苗平均高达9.62 log_2稀释倍数,常规疫苗平均为8.78log_2稀释倍数,差异显著(P0.05)。试验表明:疫苗病毒细胞收获液进行膜纯化技术处理后,免疫效果显著优于未经纯化的常规灭活疫苗。  相似文献   
37.
通过对仙游县2014年秋季猪O型口蹄疫免疫抗体检测,了解和掌握仙游县猪口蹄疫免疫效果,以更好地指导今后动物疫病防控工作。  相似文献   
38.
本试验在断奶仔猪饲粮中添加不同水平的粪肠球菌,研究其替代抗生素对断奶仔猪生长性能、腹泻指数和腹泻率、血液生化指标以及免疫器官的影响。选取120头(28±2)日龄平均体重为(7.60±0.81)kg的"杜×长×大"断奶仔猪,随机分为5组,每组6个重复(公母各占1/2),每个重复4头,每个重复为1圈。对照组饲喂基础饲粮,抗生素组在基础饲粮中添加100mg/kg硫酸黏菌素和400 mg/kg杆菌肽锌,3个粪肠球菌组分别在基础饲粮中添加40、200和1 000 mg/kg粪肠球菌,试验期31 d。试验结果显示:1)在1~14 d,饲粮中添加抗生素和粪肠球菌对断奶仔猪的平均日采食量(ADFI)、平均日增重(ADG)以及料重比(F/G)无显著影响(P0.05)。在15~31 d,与对照组和抗生素组相比,200和1 000 mg/kg组可极显著提高ADFI和ADG(P0.01)。在1~31 d,与对照组相比,200和1 000 mg/kg组的ADFI均极显著提高(P0.01),而ADG分别显著和极显著增加(P0.05和P0.01);与抗生素组相比,1 000 mg/kg组可极显著提高ADFI(P0.01),而200和1 000 mg/kg组的ADG分别显著和极显著增加(P0.05和P0.01)。2)在1~14 d,与对照组相比,40 mg/kg组的腹泻指数和腹泻率显著降低(P0.05)。在15~31 d和1~31 d,与对照组和抗生素组相比,40和1 000 mg/kg组均可在一定程度上降低腹泻率(P0.05)。3)与对照组相比,粪肠球菌可以显著提高血液中总蛋白含量(P0.05),其中200和1 000 mg/kg组达到极显著水平(P0.01),且这2组分别可以显著和极显著提高球蛋白含量(P0.05和P0.01)。与抗生素组相比,200和1 000 mg/kg组可以显著提高总蛋白含量(P0.05)。与对照组相比,抗生素组和1 000 mg/kg组的白球比显著降低(P0.05),另外,抗生素组血液中谷丙转氨酶和谷草转氨酶活性显著降低(P0.05),200 mg/kg组的谷丙转氨酶活性显著降低(P0.05)。4)与对照组相比,1 000 mg/kg组的肝脏重量和脾脏指数有一定程度的提高(P0.05),与抗生素组相比,200和1 000 mg/kg组可显著提高肝脏重量(P0.05)。结果表明,饲粮中添加粪肠球菌可改善断奶仔猪的生长性能(饲喂15~31 d),降低腹泻率,提高仔猪免疫力,其中添加量为1 000 mg/kg时效果最好。  相似文献   
39.
为了探讨在饲粮中添加不同水平紫苏籽提取物对蛋鸡产蛋高峰后期生产性能、生殖激素及免疫功能的影响,本试验选用体重、产蛋率基本一致的48周龄海兰褐蛋鸡480只,采用单因素完全随机试验设计,随机分为4组,每组6个重复,每个重复20只。对照组饲喂基础饲粮,试验Ⅰ、Ⅱ、Ⅲ组分别在基础饲粮中添加0.01%、0.02%、0.03%的紫苏籽提取物,试验期30 d。结果表明:1)与对照组相比,饲粮中添加0.01%、0.02%、0.03%紫苏籽提取物均能降低料蛋比,但差异不显著(P0.05),4组间日均采食量、破软蛋率无显著差异(P0.05),添加0.03%紫苏籽提取物能极显著提高蛋鸡产蛋率和日均产蛋量(P0.01);2)与对照组相比,添加0.01%、0.02%、0.03%紫苏籽提取物能极显著提高蛋鸡血清中孕酮(第15天)和雌二醇(第15和30天)的含量(P0.01),添加0.03%紫苏籽提取物能极显著降低蛋鸡血清中睾酮含量(P0.01);3)与对照组相比,添加0.01%、0.02%、0.03%紫苏籽提取物能极显著提高蛋鸡血清中白细胞介素-2(IL-2)含量(P0.01),添加0.02%、0.03%紫苏籽提取物能极显著提高蛋鸡血清中免疫球蛋白G(Ig G)含量(P0.01),添加0.03%紫苏籽提取物能极显著提高蛋鸡血清中免疫球蛋白A(Ig A)含量(P0.01)。由此可知,饲粮中紫苏籽提取物添加水平为0.03%时,能极显著提高蛋鸡产蛋高峰后期产蛋率、日均产蛋量和免疫功能。  相似文献   
40.
本试验旨在以"无菌鸡"为模型,研究添加鸡源性乳酸菌和盲肠内容物后,对仔鸡肠道发育、黏膜形态及免疫器官发育的影响。试验选用无特定病原体(SPF)种蛋80枚,经无菌孵化后,选择健康仔鸡60羽,分3组(每组20羽),转入3台无菌隔离器内饲养,并分别饲喂:无菌饲粮(CT组)、无菌饲粮+乳酸菌液(LB组)、无菌饲粮+鸡盲肠内容物(CC组);饲养21 d后试验结束,于试验7、14、21日齡从各组取6只进行屠宰,测定鸡肠道各段长度和免疫器官重量,并对肠道黏膜形态显微观察。结果显示:饲喂乳酸菌或盲肠内容物的仔鸡各阶段中的空肠长度均高于CT组,盲肠长度和体积均低于CT组的无菌鸡;仔鸡的脾脏指数高于CT组(P=0.010);饲喂乳酸菌或盲肠内容物后仔鸡的十二指肠、空肠和回肠隐窝深度降低、绒毛高度/隐窝深度增大。本试验说明,饲喂肠道菌群能促进仔鸡肠道发育,盲肠体积变小;同时促进脾脏的发育,提高机体免疫力。  相似文献   
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