Cryptosporidium are important causative parasitic protozoa that cause gastrointestinal discomfort and diarrhea in humans and animals, posing a huge threat to public health. Ruminants serve as the main source of Cryptosporidium infection. However, the relationship between this intestinal parasite and host gut microbiota in Tibetan sheep remains almost unknown. In the present study, using nested PCR targeting the SSU rRNA gene, we detected Cryptosporidium in 9% (38/420) of fecal samples. The positive rate was significantly higher in 4-7 month-old lambs than in adult sheep. Infection of Cryptosporidium spp. was associated with limited overall structural and functional alterations of the host gut microbiota, characterized by increased the relative abundance of Escherichia and reduced functional pathways related to amino acid biosynthesis and nucleotide/nucleoside biosynthesis. Additionally, the data indicates that age served as a primary determinant of the gut microbiota, whereas Cryptosporidium load showed no significant association with microbial variation. Machine learning model analysis revealed that these differential microbial features could effectively discriminate between infected and uninfected animals. These findings elucidate that Cryptosporidium infection is associated with specific and limited gut microbiota alterations in sheep.

Helminths can manipulate their host’s gut microbiota, with the expansion of the lactobacilli population being a common feature. This process profoundly influences host immunoregulation, yet the underlying mechanisms remain almost unknown. Using a tissue-dwelling helminth model (larval Echinococcus multilocularis) while validating key findings from other helminth infections, we show that helminths harness the antibacterial program of host innate immunity to transform the host gut microbiome and control gut microbiota-mediated immunity. Using multifaceted techniques, we elucidate that cathelicidin-related antimicrobial peptide (CRAMP), derived from the expanded CD11b+CD206+ macrophages rather than the intestinal epithelial cells, is the key component that enters into the gut ecological system and enhances the fitness of Lactobacillus by selectively killing gram-negative microbes like enterobacteria. Furthermore, through in vitro cell culturing and in vivo dietary intervention experiments, we demonstrate that this regulation from innate immunity is boosted via toll-like receptor signaling by helminth’s secretory products, which could be sufficiently tuned down by dietary vitamin D through its receptor and cyp27b1. Importantly, using microbiota-targeted treatment methods, we prove that this signaling bolsters gut microbiota-mediated host intestinal Foxp3+ Treg cell expansion and parasite survival and that therapies targeting this signaling are effective in treating infection. We outline a dietary micronutrient-dependent mechanism by which helminths leverage host innate immunity to edit the host gut microbiome and thereby control immunosuppression precisely.

Monieziasis is a prevalent issue in small ruminant husbandry, primarily caused by Moniezia expansa and M. benedeni in China. There is a critical need for highly sensitive methods for disease surveillance and prevention. In this study, we developed a visual assay combining recombinase polymerase amplification (RPA) with a lateral flow strip (RPA-LFD) for the rapid detection of Moniezia spp. in sheep fecal samples. Seven primer/probe sets were designed based on a specific fragment of the M. expansa β-tubulin gene (MTUB). The RPA-LFD assay performed optimally under reaction conditions of 39 ℃ for 15 min, with a primer-to-probe ratio of 4:0.6. The optimized method demonstrated high specificity for Moniezia spp., with no cross-reactivity with genomic DNA from other common gastrointestinal parasites in ruminant livestock. The detection limit was 10 copies/μL of plasmid DNA or 10 pg/μL of M. expansa genomic DNA per reaction. When compared to PCR using clinical and sheep-simulated samples, the RPA-LFD assay exhibited equivalent detection capability, achieving 95.7 % consistency (K value = 0.939, p < 0.001). These results suggest that the RPA-LFD method is a reliable and portable diagnostic tool for routine screening, monitoring, and rapid confirmation of monieziasis in sheep flocks, particularly in endemic areas and remote regions.

Ovine theileriosis is an important tick-borne protozoan disease. It has been reported that three Theileria species are responsible for ovine theileriosis in China, which are T. luwenshuni, T. uilenbergi, and T. ovis. Here, we established three detection techniques based on loop-mediated isothermal amplification (LAMP) and nanoparticle-based lateral flow biosensor (LFB) for the infection of the three Theileria species. Three LAMP primer sets were designed targeting the nucleotide sequences of the 28S rRNA gene of T. luwenshuni, T. uilenbergi, and T. ovis. We used LAMP coupled with real-time fluorescence detection to optimize the concentrations of dNTP Mix, MgSO4, and Bst 2.0 DNA polymerase, as well as the reaction temperature of the LAMP assay, and then combined LAMP with LFB (LAMP-LFB). The entire detection assay process, including genomic DNA extraction (40 min), LAMP reaction (40 min), and LFB readout (<5 min), can be completed within 85 min. The established assays can specifically detect species of T. luwenshuni, T. uilenbergi, and T. ovis infection without cross-reaction with other Theileria, Babesia, and Anaplasma species. The detection limits of the LAMP-LFB assays for T. luwenshuni, T. uilenbergi, and T. ovis plasmid templates were 2.72 × 102 copies/μL, 2.96 × 103 copies/μL, and 3.05 × 101 copies/μL, respectively. Finally, we compared the established LAMP-LFB assay with the traditional PCR assay. The results showed that the total coincidence rates were 96.67 % (T. luwenshuni), 96.67 % (T. uilenbergi), and 93.33 % (T. ovis), respectively. In general, we developed a rapid, simple, sensitive, and specific technique for differential detection of T. luwenshuni, T. uilenbergi, and T. ovis infection in small ruminants.

Helminths serve as principal regulators in modulating host immune responses, and their excretory-secretory proteins are recognized as potential therapeutic agents for inflammatory bowel disease. Nevertheless, our comprehension of the mechanisms underlying immunoregulation remains restricted. This investigation delves into the immunomodulatory role of a secretory protein serpin (Emu-serpin), within the larval stage of Echinococcus multilocularis. Our observations indicate that Emu-serpin effectively alleviates dextran sulfate sodium-induced colitis, yielding a substantial reduction in immunopathology and an augmentation of anti-inflammatory cytokines. Furthermore, this suppressive regulatory effect is concomitant with the reduction of gut microbiota dysbiosis linked to colitis, as evidenced by a marked impediment to the expansion of the pathobiont taxa Enterobacteriaceae. In vivo experiments demonstrate that Emu-serpin facilitates the expansion of M2 phenotype macrophages while concurrently diminishing M1 phenotype macrophages, alongside an elevation in anti-inflammatory cytokine levels. Subsequent in vitro investigations involving RAW264.7 and bone marrow macrophages reveal that Emu-serpin induces a conversion of M2 macrophage populations from a pro-inflammatory to an anti-inflammatory phenotype through direct inhibition. Adoptive transfer experiments reveal the peritoneal macrophages induced by Emu-serpin alleviate colitis and gut microbiota dysbiosis. In summary, these findings propose that Emu-serpin holds the potential to regulate macrophage polarization and maintain gut microbiota homeostasis in colitis, establishing it as a promising candidate for developing helminth therapy for preventing inflammatory diseases.

Cysticercosis pisiformis, a highly prevalent parasitic disease worldwide, causes significant economic losses in the rabbit breeding industry. Previous investigations have identified a novel microRNA, designated as novel-miR1, within the serum of rabbit infected with Cysticercus pisiformis. In the present study, we found that C. pisiformis-derived novel-miR1 was released into the rabbit serum via exosomes. Through computational analysis using TargetScan, miRanda, and PITA, a total of 634 target genes of novel-miR1 were predicted. To elucidate the functional role of novel-miR1, a dual-luciferase reporter assay was utilized and demonstrated that novel-miR1 targets rabbit Toll-like receptor 2 (TLR2). Rabbit peripheral blood lymphocytes (PBLCs) were transfected with novel-miR1 mimic and mimic NC, and the in vitro experiments confirmed that novel-miR1 suppressed the expression of pro-inflammatory cytokines such as TNF-α, IL-1β, and IL-6 through the nuclear factor kappa B (NF-κB) pathway. In vivo experiments demonstrated that novel-miR1 was significantly upregulated during the 1–3 months following infection with C. pisiformis in rabbits. Notably, this upregulation coincided with a downregulation of TLR2, P65, pP65, TNF-α, IL-1β, and IL-6 in PBLCs. Collectively, these results indicate that the novel-miR1 derived from C. pisiformis inhibited the rabbits’ immune response by suppressing the NF-κB-mediated immune response. This immune modulation facilitates parasite invasion, survival, and establishment of a persistent infection.

为了深入研究猪带绦虫丝氨酸蛋白酶抑制分子(Ts-serpin-2)对THP-1细胞炎性细胞因子分泌的调节作用,本实验通过RT-PCR从猪带绦虫成虫扩增获得Ts-serpin-2(TsM_000807300)的编码序列CDS,利用毕赤酵母表达Ts-serpin-2重组蛋白.利用发色底物特异性反应检测Ts-serpin-2蛋白对猪胰蛋白酶、胰弹性蛋白酶、牛α-糜蛋白酶、猪胃蛋白酶、木瓜酶、凝血酶和组织蛋白酶G的抑制效果.重组蛋白Ts-serpin-2处理THP-1细胞24 h,应用qRT-PCR和ELISA方法检测各炎性细胞因子差异表达水平.结果显示,真核酵母表达的重组蛋白Ts-serpin-2分子量约为48 kDa,具有蛋白酶抑制活性,对牛α-糜蛋白酶、猪胰弹性蛋白酶及猪胰蛋白酶的活性均有明显的抑制作用.重组蛋白Ts-serpin-2可抑制LPS活化的THP-1细胞促炎性细胞因子IL-1β、IL-6、IL-12α、IFN-γ和iNOS2 mRNA的转录水平,促进IL-4刺激的THP-1细胞抗炎性细胞因子IL-10的表达.ELISA结果显示,Ts-serpin-2能够抑制巨噬细胞分泌致炎因子TNF-α、IL-6和IFN-γ,刺激IL-10的分泌,与qRT-PCR检测结果基本一致.上述研究结果表明猪带绦虫Ts-serpin-2可通过调节宿主巨噬细胞分泌的炎性因子影响虫体入侵过程中宿主的免疫应答.

Infection of Taenia pisiformis cysticercus is very frequently found in lagomorphs and causes serious economic losses to rabbit breeding industry. T. pisiformis cysticercus has evolved numerous strategies to manipulate their hosts. The release of exosomes is of importance in the interaction between host and parasite. However, the mechanism by which T. pisiformis cysticercus evades the host immune system for long-term survival within the host remains unclear. Using small RNA sequencing and TMT labelling proteomic, we profiled the expression patterns of miRNAs and proteins in rabbit peritoneal macrophages treated with T. pisiformis cysticercus exosomes. Seven differentially expressed (DE)-miRNAs and six DE-proteins were randomly selected to validate the accuracy of the sequencing data by qRT-PCR or western blot. Functions of DE-miRNAs and proteins were analyzed using public data bases. And DE-miRNAs-DE-proteins correlation network were established. CCK-8 assay was used to evaluate the effect of exosomes on macrophages proliferation. Cell cycle of macrophages, isolated from T. pisiformis-infected rabbits, was determined using flow cytometry. A total of 21 miRNAs were significantly differentially expressed, including three worm-derived miRNAs. The expressions of miRNAs and proteins were consistent with the sequencing results. DE-miRNAs targets were related to cell proliferation and apoptosis. Exosomes treatment resulted in a decrease of macrophages proliferation. In vivo, T. pisiformis cysticercus significantly induced S phase cell arrest. Moreover, DE-proteins were related to production of interferon-gamma and interleukin-12, and immunoregulation. Correlation network analysis revealed a negative correlation relationship between DE-miRNAs and DE-proteins. Among them, novel334 and tpi-let-7-5p have potential regulatory effects on IL1β and NFκB2 respectively, which imply that novel334-IL1β/tpi-let-7-5p-NFκB2 axis may be an important way that T. pisiformis cysticercus modulates host immune response through exosomes. Further understanding of these potential regulatory mechanisms will contribute to clarify the mechanism of escape mediated by T. pisiformis exosomes.

目的 建立检测家兔豆状囊尾蚴感染的滚环扩增(RCA)方法.方法 以家兔血清中豆状囊尾蚴来源的novel-miR1为诊断靶标,设计连接序列和锁式探针,并对连接序列和锁式探针的比例、反应时间、酶用量、dNTP用量以及扩增反应时间等5个重要条件进行优化,建立检测豆状囊尾蚴感染的RCA方法.将novel-miR1标准品倍比稀释为1 fmol/L至100 nmol/L的9个不同浓度的样品,评价RCA方法的灵敏度.用优化后的RCA方法分别检测健康家兔和豆状囊尾蚴感染家兔血清miRNA各20份(实验室保存样品),并通过受试者工作特征(ROC)曲线分析其敏感性和特异性.20只雌性家兔每只经口感染1 000个豆状带绦虫虫卵,采集感染前和感染后每个月的家兔血样制备血清miRNA,用优化后的RCA方法进行检测,评价其应用效果.结果 电泳结果显示,RCA扩增产物的DNA停留在加样孔中,形成一条明亮条带.反应条件优化试验结果显示,连接序列浓度为2μmol/L、锁式探针浓度为1μmol/L(连接序列和锁式探针的比为2:1)、T4 DNA连接酶为350 U、连接180 min时连接效率最高.在100μl的扩增体系中,dNTP浓度为0.5 μmol/L,扩增240 min时,RCA扩增效果最佳.优化后RCA的最低检测浓度为10 pmoI/L.RCA检测健康家兔和豆状囊尾蚴感染家兔血清miRNA样品的平均荧光值分别为53.298±1.707和97.498±5.892,差异有统计学意义(t=7.206,P＜0.01).ROC分析结果显示,当阳性临界值为61.69时,RCA方法的敏感性和特异性均为95％,AUC为0.955 0,似然比为19.00.RCA检测豆状囊尾蚴感染后不同时间的家兔血清miRNA结果显示,20份感染前的血清中19份检测结果为阴性,1份为阳性;感染后1个月的血清中,17份为阳性,2份为疑似,1份为阴性;感染后2个月的血清,1份为阴性,其余为阳性;感染后3个月的血清,3份为阴性,其余为阳性.结论 建立了检测家兔豆状囊尾蚴感染的RCA方法,该方法在豆状囊尾蚴感染后3个月内的家兔血清中检出novel-miR1,具有良好的应用潜力..

The small ubiquitin-like modifier (SUMO) plays important roles, with the SUMOylation pathway as one of its core components. In the present work, a single SUMO gene was initially identified from Taenia pisiformis and designated as TpSUMO. Bioinformatic analysis showed that the TpSUMO gene contained a 309 bp open reading frame (ORF), encoding 102 amino acids, and had a predicted molecular weight of ∼12 kDa. The amino acid sequence of TpSUMO was deduced and it shared 44.00% identity with human SUMO2 (HsSUMO2) and exhibited more than 97.78% identity with SUMOs from Taenia and Echinococcus. TpSUMO possessed a putative non-consensus site (FK11MG) within its N-terminus and a typical di-glycine (GG) motif at the C-terminus. Basic local alignment search tool (BLAST) analysis showed that only a single SUMO-related ortholog was present in each set of known genome data for fourteen tapeworm species. The precursor His-TpSUMO-FL, mature His-TpSUMO-GG and mutant His-TpSUMO-GGK11R proteins (∼18 kDa) were expressed in Escherichia coli Rosseta (DE3), and rabbit polyclonal anti-TpSUMO was generated with a high titer of 1.28 × 105. In vitro SUMOylation assay results showed that TpSUMO multimer formation in the His-TpSUMO-GG reaction could be catalyzed by the human SAE1/SAE2 and UBC9 conjugation system, but K11R mutation disrupted TpSUMO chain synthesis. Quantitative real-time PCR (qRT-PCR) further revealed that TpSUMO was ubiquitously expressed in different stages of T. pisiformis and in higher levels during an early development phase (day 14) of adult worms. Immunofluorescence localization showed that TpSUMO was detected in the bladder wall of cysticerci, in the testis in immature segment, and within eggs in the gravid proglottids. These findings indicated that TpSUMO is a new member of the SUMO protein family and may play a vital role in regulation of functions within proteins involved in worm growth and development.

Helminth infection affects over 1 billion people worldwide. However, its relationship with the gut mycobiome remains unknown.

目的 建立豆状囊尾蚴体外长期培养方法,并对其培养分泌产物进行鉴定.方法 将豆状带绦虫虫卵经口感染新西兰白兔(2 000枚/只),感染后3个月,从感染兔腹腔中收集豆状囊尾蚴.将虫体随机分为PBS组、RPMI1640组、胆汁组(RPMI1640+10％兔胆汁)和血清组(RPMI1640+10％无外泌体胎牛血清),10个/组,37℃、5％CO2培养后5min、1h、2h、12h、24 h、36 h、48 h及其后每天进行观察,记录豆状囊尾蚴头节翻出情况、虫体活力、体外存活时间及形态改变等,筛选适宜的培养条件.取50个幼虫在细胞瓶(25 cm2)中按筛选出的培养条件培养,每隔48小时收集培养液离心浓缩,取上清,蛋白质免疫印迹(Western blotting)检测豆状带绦虫烯醇化酶(Tpeno)和Tp14-3-3蛋白的表达情况.收集豆状囊尾蚴培养上清,提取外泌体,分别与阴性兔血清、CD63抗体、抗Tpeno单克隆抗体1D7和抗Tp14-3-3多克隆抗体孵育45 min,再加入胶体金标记的IgG,透射电镜观察外泌体形态,免疫电镜检测其标记蛋白CD63、Tpeno和Tp14-3-3表达情况.采用SPSS 20.0统计学软件进行数据分析,组间比较采用单因素方差分析.结果 培养前的豆状囊尾蚴呈椭圆形,有内凹的点状乳白色头节;PBS组可存活7d;RPMI 1640组可存活2个月;胆汁组存活时间最短,仅48h;血清组幼虫存活时间最长,可达3个月以上,高于其他3个组(P＜0.05).存活期内,PBS组、RPMI 1640组、胆汁组和血清组幼虫囊泡长度分别为(1.38±0.39)、(1.30±0.12)、(1.18±0.59)和(1.83±0.10)cm;宽度分别为(0.45±0.10)、(0.68±0.05)、(0.25±0.06)和(0.85±0.05)cm;血清组虫体囊泡长度和宽度与其余3组相比差异均有统计学意义(F长 度=7.58、65.93、7.11,F宽度=73.85、29.41、308.57,P＜0.05 或P＜0.01).培养 12 h 时,PBS组、RPMI 1640组、胆汁组和血清组幼虫头节翻出率分别为(33.3±5.8)％、(20.0±0.0)％、(100.0±0.0)％、(13.3±5.8)％,其中血清组与PBS和胆汁组头节翻出率差异有统计学意义(F=18.00、676.00,P＜0.01).对各组培养效果比较显示,血清组的培养液(RPMI 1640+10％无外泌体胎牛血清)为最适培养液.SDS-PAGE电泳分析结果显示,利用RPMI 1640+10％无外泌体胎牛血清培养豆状囊尾蚴,可成功提取到虫体的代谢_分泌产物和外泌体蛋白.Western blotting分析结果显示,用特异性抗体检测可见Tpeno和Tp14-3-3阳性条带,相对分子质量(Mr)分别约47 000和28 000,与预期相符.透射电镜下豆状囊尾蚴外泌体大小不一,直径为50～150 nm,为圆形或椭圆形的囊泡.免疫电镜分析显示,阴性兔血清不能识别外泌体蛋白,未见胶体金颗粒标记;外泌体标志蛋白CD63、虫体特异性蛋白Tpeno和Tp14-3-3均为阳性表达,胶体金颗粒标记明显.结论 初步建立了豆状囊尾蚴体外培养体系,可连续培养豆状囊尾蚴至少3个月以上.采用该体外培养方法培养可在培养上清中成功提取豆状囊尾蚴的外泌体.

BackgroundAlveolar echinococcosis (AE), which is caused by larval Echinococcus multilocularis, is one of the world's most dangerous neglected diseases. Currently, no fully effective treatments are available to cure this disease.MethodsIn vitro protoscolicidal assay along with in vivo murine models was applied in repurposing drugs against AE. Genome-wide identification and homology-based modeling were used for predicting drug targets. RNAi, enzyme assay, and RNA-Seq analyses were utilized for investigating the roles in parasite survival and validations for the drug target.FindingsWe identified nelfinavir as the most effective HIV protease inhibitor against larval E. multilocularis. Once-daily oral administration of nelfinavir for 28 days resulted in a remarkable reduction in parasite infection in either immune-competent or immunocompromised mice. E. multilocularis DNA damage-inducible 1 protein (EmuDdi1) is predicted as a target candidate for nelfinavir. We proved that EmuDdi1 is essential for parasite survival and protein excretion and acts as a functionally active protease for this helminth. We found nelfinavir is able to inhibit the proteolytic activity of recombinant EmuDdi1 and block the EmuDdi1-related pathways for protein export. With other evidence of drug efficacy comparison, our results suggest that inhibition of EmuDdi1 is a mechanism by which this HIV proteinase inhibitor mediates its antiparasitic action on echinococcosis.InterpretationThis study demonstrates that nelfinavir is a promising candidate for treating echinococcosis. This drug repurposing study proves that the widely prescribed drug for AIDS treatment is potent in combating E. multilocularis infection and thus provides valuable insights into the development of single-drug therapy for highly prevalent co-infection between HIV and helminth diseases.FundingThis work was supported by the National Natural Science Foundation of China (31802179), the Natural Science Foundation of Gansu Province, China (No. 21JR7RA027), and the State Key Laboratory of Veterinary Etiological Biology (No. SKLVEB2021YQRC01).

Taenia pisiformis is one of the most widespread gastrointestinal parasites and its larvae (cysticercosis) causes significant economic loss to rabbit industry. No efficient drug is available for this disease to date. To better understand its genomics, we assembled a 211-Mb high quality genome of T. pisiformis at chromosome level with a scaffold N50 size of 20 Mbp. Totally, 12,097 protein-coding genes was predicted from the genome. Genome-level phylogenetic analysis confirmed the taxonomic affiliations with other tapeworms and revealed that T. pisiformis diverged from its closely related relative T. hydatigena ∼ 14.6 Mya. Comparative genomic analyses revealed that the T. pisiformis genome was characterized by adaptive features of strong positive selection signals from carbohydrate/lipid metabolism and body surface integrity, and of expanded gene families related to metabolism of amino acids and lipids. The high-quality genome of T. pisiformis constitutes a resource for the comparative genomics and for further applications in general parasitology.

Cysticercus pisiformis, the larval stage of Taenia pisiformis, causes serious illness in rabbits that severely impacts the rabbit breeding industry. An inhibitive Th2 immune response can be induced by let-7-enriched exosomes derived from T. pisiformis cysticercus. However, the underlying molecular mechanisms are not completely understood. Here, we report that exosomal miR-let-7-5p released by T. pisiformis cysticercus played a critical role in the activation of M2 macrophages. We found that overexpression of let-7-5p in M1 macrophages decreased M1 phenotype expression while promoting polarization to the M2 phenotype, which is consistent with experimental data in exosome-treated macrophages alone. In contrast, knockdown of let-7-5p in exosome-like vesicles promoted M1 polarization and decreased M2 phenotype expression. Furthermore, down-regulation of transcription factor CCAAT/enhancer-binding protein (C/EBP)-δ resulted in the decrease of M1 phenotype markers and increase of M2 phenotype markers. These results suggested that let-7 enriched in exosome-like vesicles from T. pisiformis metacestodes can induce M2 macrophage polarization via targeting C/EBP δ, which may be involved in macrophage polarization induced by T. pisiformis metacestodes. The finding helps to expand our knowledge of the molecular mechanism of immunosuppression and Th2 immune response induced by metacestodes.

Taenia hydatigena, a globally distributed parasite, is a canine tapeworm and causes huge economic losses in the food industry. Using LC-MS/MS, the proteomes of T. hydatigena cyst scolex, designated as CS, and the cyst without the scolex, designated as CWS, were profiled and a total of 764 different proteins were identified, 664 of which were identified in CS, 412 identified in CWS, and 312 in both. Comparative analysis revealed that CS had more abundant proteins associated with growth and development, while CWS had more abundant proteins constituting a scaffolding and protective extracellular matrix. Consistent with the sequencing data, the abundance of the five selected proteins was validated to be higher in CWS than CS by Western blotting. The current data will provide a clue for further pinpointing a role of these proteins in the biology of T. hydatigena.

主要研究猪带绦虫丝氨酸蛋白酶抑制剂Ts-serpin-1(WormBase:TsM_000065700)对宿主THP-1细胞的免疫调节作用.通过设计特异性引物和RT-PCR扩增技术,获得Ts-serpin-1编码序列,用qRT-PCR分析Ts-serpin-1基因在猪带绦虫成虫和中绦期幼虫的表达情况;构建pCold-Ts-serpin-1原核表达载体,诱导表达纯化重组蛋白Ts-serpin-1;用重组蛋白Ts-serpin-1处理THP-1细胞,采用qRT-PCR和ELISA方法检测Ts-serpin-1处理THP-1细胞后,各炎性细胞因子的变化情况.结果显示:获得的Ts-serpin-1目的基因长度为1149 bp,编码382个氨基酸,含有Serpin家族特有的反应中心环.Ts-serpin-1基因在猪带绦虫成虫和中绦期幼虫均表达,且成虫表达量显著高于幼虫.重组蛋白Ts-serpin-1的分子质量约为43ku,可抑制THP-1细胞促炎性细胞因子IL-6、IL-1β、IL-12、TNF-α、IFN-y和iNOS2的表达,促进抗炎性细胞因子IL-10和TGF-β的分泌表达.以上结果提示,Ts-serpin-1在寄生虫-宿主互作过程中可能发挥重要作用.

为阐明猪带绦虫(Taenia solium)丝氨酸蛋白酶抑制剂(Tsserpin570)对蛋白酶的抑制作用,通过RT-PCR从猪带绦虫成虫cDNA扩增获得Tsserpin570(TsM_000807300)的完整CDS序列,并构建了 pCold-Tsserpin570原核表达载体,利用发色底物法检测可溶性重组蛋白Tsserpin570对蛋白酶活性的抑制作用.结果显示:RT-PCR扩增获得的Tsserpin570基因片段长1 206 bp,其蛋白的分子质量为46 ku,含有serpin家族特有的反应中心环及DEEGAE和FIVDHPFLFFI家族保守序列.qRT-PCR结果显示,Tsserpin570基因在猪带绦虫成虫和囊尾蚴阶段均有表达,且在成虫的表达量显著高于囊尾蚴的.pCold-Tsserpin570原核表达载体经IPTG诱导表达后获得可溶性重组蛋白Tsserpin570,可被猪囊尾蚴阳性血清识别.基于发色底物法检测Tsserpin570对牛α-胰糜蛋白酶、猪胰弹性蛋白酶、猪胰蛋白酶、人白细胞组织蛋白酶G、人血浆凝血酶、猪胃蛋白酶和木瓜蛋白酶等蛋白酶的活性抑制作用发现,其对牛α-胰糜蛋白酶、胰蛋白酶及弹性蛋白酶的活性均有明显的抑制作用.以上结果提示,Tsserpin570对多种丝氨酸蛋白酶均具有较强的抑制作用.

目的 建立一种多重聚合酶链式反应(multiplex polymerase chain reaction,mPCR)方法,用于快速鉴别猪囊尾蚴等4种猪的绦虫蚴.方法 比较猪带绦虫(Taenia solium)、亚洲带绦虫(Taenia asiatica)、细粒棘球绦虫(Echinococcusgranulosus)和泡状带绦虫(Taenia hydatigena)的线粒体基因组,选取tRNA-Val、tRNA-Ala、tRNA-Asp和nad1基因作为分子检测靶标,设计4条种特异性上游引物(TaF、EgF、ThF、和TsF)和1条下游通用引物(TR),通过优化反应条件和体系,建立了在一个PCR体系中即可完成对4种猪绦虫蚴的快速鉴别的mPCR方法.结果 4种猪绦虫蚴的特异性PCR引物等比例混合后,在退火温度为50℃的条件下,该mPCR方法可同时扩增出C.cellulosae、T.asiatica、E.granulosus和C.tenuicol-lis的特异性基因片段,其大小分别为478 bp、710 bp、619 bp和542 bp.PCR产物测序后经BLAST比对,与同种虫体的基因序列相似性在99％以上.结论 本研究建立的mPCR方法具有很高的种间特异性,并且可通过扩增片段的大小对4种猪绦虫蚴进行快速、准确的鉴别.

Taenia hydatigena is a widespread gastrointestinal helminth that causes significant health problems in livestock industry. This parasite can survive in a remarkably wide range of intermediate hosts and affects the transmission dynamics of zoonotic parasites. T. hydatigena is therefore of particular interest to researchers interested in studying zoonotic diseases and the evolutionary strategies of parasites. Herein we report a high-quality draft genome for this tapeworm, characterized by some hallmarks (e.g., expanded genome size, wide integrations of viral-like sequences and extensive alternative splicing during development), and specialized adaptations related to its parasitic fitness (e.g., adaptive evolutions for teguments and lipid metabolism). Importantly, in contrast with the evolutionarily close trematodes, which achieve gene diversification associated with immunosuppression by gene family expansions, in T. hydatigena and other cestodes, this is accomplished by alternative splicing and gene loss. This indicates that these two classes have evolved different mechanisms for survival. In addition, molecular targets for diagnosis and intervention were identified to facilitate the development of control interventions. Overall, this work uncovers new strategies by which helminths evolved to interact with their hosts.