In infectious pancreatic necrosis virus carrier Atlantic salmon, Salmo salar L., post-smolts, almost all kidney macrophages ex vivo contain a low level of non-replicating virus

The level of infection by infectious pancreatic necrosis virus (IPNV) of kidney macrophages from 12 asymptomatic carrier Atlantic salmon post-smolts was studied. Kidney leucocytes were fractionated on 34/51% Percoll gradients, allowed to adhere to plastic wells overnight, washed to remove non-adherent cells and cultured for up to 7 days with or without renewal of medium on day 3. On day 1, supernatants were harvested, macrophages were counted, lysed and IPNV in the supernatants and lysates was titred in chinook salmon embryo (CHSE-214) cells. The multiplicity of infection ranged between 1:2.2 and 1:7.4 (virus:macrophages). On day 3, the titres of IPNV in macrophage lysates decreased and in wells where the medium was renewed on day 3, IPNV was no longer detectable on day 7. In the supernatants, one fish was positive for IPNV on day 1, four fish on day 3 but none were detectably positive on day 7. In parallel wells in which the medium was not renewed, on day 7 IPNV was detected in macrophage lysates of three fish and the supernatants were also IPNV positive in two of these fish. This suggests that virus might be shed from infected macrophages and then reinfect other macrophages. When macrophages were serially diluted in wells and cultured for 24 h, IPNV could be cultured from macrophage lysates of wells containing between two and 70 macrophages. These results indicate that a very high proportion of the adherent kidney macrophages must be infected with very few non-replicating virions.     

牛磺酸对有丝分裂原刺激的小鼠免疫细胞功能的影响

为探讨牛磺酸对有丝分裂原刺激的小鼠免疫细胞功能的影响,本实验体外设计了终浓度为0.5、5、50、和500μg/mL四个浓度梯度。开展了Tau对有丝分裂原刺激的小鼠腹腔巨噬细胞和脾淋巴细胞功能影响的研究。结果Tau对LPS刺激的腹腔巨噬细胞分泌IL-1β具有免疫增强作用;对LPS刺激的小鼠腹腔巨噬细胞的增殖反应无显著作用。Tau对LPS刺激的脾淋巴细胞增殖反应在一定浓度范围内无显著作用,但当浓度较高时,有显著的抑制作用;Tau对ConA刺激的脾淋巴细胞分泌IL-2具有极显著的增强和调节作用;Tau在较高浓度时对LPS刺激的脾淋巴细胞分泌IgG也具有极显著的促进作用。牛磺酸对有丝分裂原刺激的小鼠腹腔巨噬细胞和脾淋巴细胞的免疫功能具有增强和调节作用。     

SCAMP对小鼠免疫系统功能影响的探讨

小鼠腹腔注射不同剂量的鲨鱼软骨酸性粘多糖 (SCAMP)后 ,其胸、脾指数增高 ,并在一定剂量范围内有浓度依赖关系。 5mg/kg体重剂量的SCAMP能显著活化小鼠腹腔巨噬细胞 ,与对照组相比 ,试验组巨噬细胞在外观形态上微绒毛变少、变长 ,伪足伸出 ,形状变得不规则 ;免疫球蛋白G含量也明显增加 ,同时小鼠腹腔巨噬细胞中酸性磷酸酶和谷胱甘肽过氧化物酶活性增加。     

枸杞多糖对小鼠体内外免疫巨噬细胞功能的影响

探讨枸杞多糖（LBP）对小鼠体内外免疫巨噬细胞功能的影响。本研究分别通过小鼠碳粒廓清实验、直接对小鼠原代单核巨噬细胞进行刺激和MTT比色的方法来研究枸杞多糖（LBP）对小鼠体内外单核免疫巨噬细胞的影响。     

Profiling microRNA expression in bovine alveolar macrophages using RNA-seq

MicroRNAs (miRNAs) are important regulators of gene expression and are known to play a key role in regulating both adaptive and innate immunity. Bovine alveolar macrophages (BAMs) help maintain lung homeostasis and constitute the front line of host defense against several infectious respiratory diseases, such as bovine tuberculosis. Little is known, however, about the role miRNAs play in these cells. In this study, we used a high-throughput sequencing approach, RNA-seq, to determine the expression levels of known and novel miRNAs in unchallenged BAMs isolated from lung lavages of eight different healthy Holstein–Friesian male calves. Approximately 80 million sequence reads were generated from eight BAM miRNA Illumina sequencing libraries, and 80 miRNAs were identified as being expressed in BAMs at a threshold of at least 100 reads per million (RPM). The expression levels of miRNAs varied over a large dynamic range, with a few miRNAs expressed at very high levels (up to 800,000 RPM), and the majority lowly expressed. Notably, many of the most highly expressed miRNAs in BAMs have known roles in regulating immunity in other species (e.g. bta-let-7i, bta-miR-21, bta-miR-27, bta-miR-99b, bta-miR-146, bta-miR-147, bta-miR-155 and bta-miR-223). The most highly expressed miRNA in BAMs was miR-21, which has been shown to regulate the expression of antimicrobial peptides in Mycobacterium leprae-infected human monocytes. Furthermore, the predicted target genes of BAM-expressed miRNAs were found to be statistically enriched for roles in innate immunity. In addition to profiling the expression of known miRNAs, the RNA-seq data was also analysed to identify potentially novel bovine miRNAs. One putatively novel bovine miRNA was identified. To the best of our knowledge, this is the first RNA-seq study to profile miRNA expression in BAMs and provides an important reference dataset for investigating the regulatory roles miRNAs play in this important immune cell type.     

紫衫醇对小鼠不同组织巨噬细胞功能的影响

为了探讨紫杉醇(Paclitaxel,PA)对小鼠不同组织巨噬细胞增殖和功能的影响。无菌操作制备小鼠腹腔、骨髓和脾脏巨噬细胞,在体外细胞培养体系中分别加入不同浓度40、80、160 ng/mL的PA和脂多糖(LPS)共培养,采用MTT法检测细胞增殖,ELISA和Griess法分别检测细胞分泌TNF-α和NO量,瑞氏-吉姆萨染色法测定腹腔巨噬细胞吞噬能力。结果表明： PA促进腹腔巨噬细胞和LPS诱导的腹腔和骨髓巨噬细胞增殖,但抑制脾脏和骨髓巨噬细胞以及LPS诱导的脾脏巨噬细胞增殖;PA抑制不同组织巨噬细胞分泌TNF-α,但促进腹腔和脾脏巨噬细胞分泌NO;PA提高了腹腔巨噬细胞吞噬鸡红细胞的能力。PA对小鼠不同组织巨噬细胞的免疫功能均有影响,这为进一步阐明PA的免疫调节机理提供了新的理论依据。     

重组tHsp70对罗非鱼腹腔巨噬细胞免疫功能的影响

利用酵母分泌表达的重组罗非鱼热休克蛋白70(heat shock protein 70 of tilapia,tHsp70),与海豚链球菌(Streptococcus iniae)抗原在体外非共价结合形成tHsp70-抗原复合物,通过对体外培养的腹腔巨噬细胞NO释放水平、吞噬活性及免疫相关基因表达进行检测,研究tHsp70对罗非鱼细胞免疫功能的影响。结果显示,tHsp70在体外能够与海豚链球菌菌体、胞外分泌物(extracellular bacteria products,ECP)结合形成tHsp70-抗原复合物;tHsp70-抗原复合物和tHsp70均可显著增强罗非鱼腹腔巨噬细胞的贴壁和生长、NO释放及吞噬活性(P<0.01),而ECP单独作用可引起腹腔巨噬细胞死亡,显著降低腹腔巨噬细胞NO释放(P<0.05),但tHsp70与ECP体外非共价结合后可减轻ECP对巨噬细胞的损伤;tHsp70-抗原复合物和tHsp70作用于腹腔巨噬细胞,白细胞介素8(IL-8),热休克蛋白70(HSP70),CXC趋化因子受体4(CXCR4)和颗粒蛋白前体(PGRN)4个基因的表达量均显著高于海豚链球菌抗原单独刺激和无刺激对照组(P<0.01)。研究表明tHsp70具有免疫增强和免疫佐剂的功能,为开发罗非鱼链球菌病Hsp70-肽疫苗提供了实验依据。     

动物铁过负荷的临床和实验室诊断技术

为动物铁过负荷建立简单、快捷的临床和实验室诊断技术,利用临床自然病例,采用病理解剖学、组织学和组织化学染色技术,对病猪及病犬的淋巴结、脾脏、肺脏、肝脏和肾脏进行了病理解剖学和组织病理学观察和研究.结果表明,随着铁过负荷的程度不同,富含巨噬细胞的淋巴结呈现出由棕黄色至棕褐色的不同色泽;在H.E染色的组织学标本中,可见巨噬细胞内含有数量不等的棕黄色含铁血黄素颗粒;在普鲁氏蓝染色的组织学标本中,含铁血黄素颗粒则呈蓝色.动物发生铁过负荷时,过剩的铁主要沉积在单核巨噬细胞系统的胞浆内,其次是肝细胞的胞浆内.     

Identification of genes required for the fitness of Rhodococcus equi during the infection of mice via signature-tagged transposon mutagenesis

Rhodococcus equi is a Gram-positive facultative intracellular bacterium that causes pyogranulomatous pneumonia in foals and immunocompromised people. In the present study, signature-tagged transposon mutagenesis was applied for the negative selection of R. equi mutants that cannot survive in vivo. Twenty-five distinguishable plasmid-transposon (plasposon) vectors by polymerase chain reaction (PCR), each containing a unique oligonucleotide tag, were constructed and used to select the transposon mutants that have in vivo fitness defects using a mouse systemic infection model. Of the 4,560 transposon mutants, 102 mutants were isolated via a real-time PCR-based screening as the mutants were unable to survive in the mouse model. Finally, 50 single transposon insertion sites were determined via the self-cloning strategy. The insertion of the transposon was seen on the virulence plasmid in 15 of the 50 mutants, whereas the remaining 35 mutants had the insertion of transposon on the chromosome. The chromosomal mutants contained transposon insertions in genes involved in cellular metabolism, DNA repair and recombination, gene regulation, non-ribosomal peptide synthesis, and unknown functions. Additionally, seven of the chromosomal mutants showed a reduced ability to multiply in the macrophages in vitro. In this study, we have identified several biosynthetic pathways as fitness factors associated with the growth within macrophages and survival in mice.     

PCV2感染对猪肺泡巨噬细胞Fc受体数量和吞噬功能的影响

将猪圆环病毒2型(PCV2)BF株经口、鼻接种40日龄健康普通仔猪,在接种后不同时间宰杀,收集肺泡巨噬细胞(PAM),同时设立对照组。用EA花环试验测定Fc受体数目,用吞噬鸡红细胞试验测定吞噬功能,来分析PCV2感染对PAM某些生物学活性的影响。结果显示,PAM表面Fc受体数和吞噬鸡红细胞数的变化规律一致,与对照组相比,两者数量在接种后3 d时下降至最低,之后回升,14 d时基本恢复正常。本研究表明,PCV2感染可引起PAM吞噬和清除病原的能力出现短暂下降。