Influenza viruses are major respiratory pathogens known to infect human and a variety of animals and are widely prevalent worldwide.Genome structure of influenza D virus(IDV)is identical to that of influenza C virus(I...Influenza viruses are major respiratory pathogens known to infect human and a variety of animals and are widely prevalent worldwide.Genome structure of influenza D virus(IDV)is identical to that of influenza C virus(ICV),and phylogenetic analyses suggest that IDV and ICV share a common ancestry and high homology.To date,the prevalence of ICV and IDV in China is unclear,but these viruses represent a potential threat to public health due to cross-species transmission and zoonotic potential.To efficiently monitor ICV and IDV,it is necessary to establish a dual detection method to understand their prevalence and conduct in-depth research.A duplex real-time PCR method for the simultaneous detection of ICV and IDV was developed.TaqMan fluorescent probes and specific primers targeting NP gene of ICV and PB1 gene of IDV were designed.This method exhibited good specificity and sensitivity,and the detection limit reached 1 × 10^(1) copies/pL of plasmid standards of each pathogen.Thirty-one clinical swine samples and 10 clinical cattle samples were analyzed using this method.One positive sample of IDV was detected,and the accuracy of clinical test results was verified by conventional PCR and DNA sequencing.The duplex real-time PCR detection method represents a sensitive and specific tool to detect IG/and IDV,It provides technical support for virus research and clinical diagnosis of ICV and IDV.This information will benefit animal and human health.展开更多
C-type lectin receptors (CLRs) are representative pattern recognition receptors that recognize microbial polysaccharides expressed on antigen-presenting cells. In the present study, we carried out further detailed ana...C-type lectin receptors (CLRs) are representative pattern recognition receptors that recognize microbial polysaccharides expressed on antigen-presenting cells. In the present study, we carried out further detailed analysis on the involvement of Dectin-2, a CLR that senses high mannose polysaccharide, in innate immune responses induced by influenza virus hemagglutinin (HA). Treatment of HA with periodate or PNGase F induced lower interleukin (IL)-12p40 secretion by conventional dendritic cells (DCs) compared with the untreated group. In contrast, treatment with O-glycosidase did not affect cytokine production. Green fluorescent protein expression in canonical Dectin-2-transducing cells was approximately 3% - 12% following HA stimulation, except with the A/H1N1pdm09 subtype HA. This expression was markedly reduced in cells possessing mutated amino acids in the carbohydrate recognition domain of Dectin-2, especially following stimulation with HA derived from the A/H3N2 subtype. Interferon (IFN)-α production from CD11c<sup>+</sup>Siglec-H<sup>+</sup>PDCA-1<sup>+</sup> plasmacytoid DCs was significantly increased in Dectin-2 knockout mice compared with wild-type mice upon stimulation with HA except for the B/Yamagata lineage HA. These results suggested that Dectin-2 is involved in initiating inflammatory responses via mannose polysaccharide on HA. However, other mechanisms may function in the antiviral response, including the type I IFN axis.展开更多
Influenza C virus, a member of the Orthomyxoviridae family, causes flu-like disease but typically only with mild symptoms. Humans are the main reservoir of the virus, but it also infects pigs and dogs. Very recently, ...Influenza C virus, a member of the Orthomyxoviridae family, causes flu-like disease but typically only with mild symptoms. Humans are the main reservoir of the virus, but it also infects pigs and dogs. Very recently, influenza C-like viruses were isolated from pigs and cattle that differ from classical influenza C virus and might constitute a new influenza virus genus. Influenza C virus is unique since it contains only one spike protein, the hemagglu- tinin-esterase-fusion glycoprotein HEF that possesses receptor binding, receptor destroying and membrane fusion activities, thus combining the functions of Hemaggiutinin （HA） and Neuraminidase （NA） of influenza A and B viruses. Here we briefly review the epidemiology and pathology of the virus and the morphology of virus particles and their genome. The main focus is on the structure of the HEF protein as well as on its co- and post- translational modification, such as N-glycosylation, disulfide bond formation, S-acylation and proteolytic cleavage into HEF1 and HEF2 subunits. Finally, we describe the functions of HEF： receptor binding, esterase activity and membrane fusion.展开更多
目的探讨合并肺炎的甲型H1N1流感患者血浆中相关细胞因子、C反应蛋白(CRP)及T淋巴细胞计数在病程中的变化特征,为临床早期诊断与治疗提供参考。方法检测16例合并肺炎的住院甲型H1N1流感患者血浆中相关细胞因子[γ干扰素(IFN-γ),白细胞...目的探讨合并肺炎的甲型H1N1流感患者血浆中相关细胞因子、C反应蛋白(CRP)及T淋巴细胞计数在病程中的变化特征,为临床早期诊断与治疗提供参考。方法检测16例合并肺炎的住院甲型H1N1流感患者血浆中相关细胞因子[γ干扰素(IFN-γ),白细胞介素6(IL-6),白细胞介素8(IL-8),肿瘤坏死因子-α(TNF-α),转化生长因子-β1(TGF-β1)]水平、CRP及T淋巴细胞计数的变化。根据患者入院时血气分析中动脉血氧分压(PaO2)水平,分为重症组(PaO2<60 mm Hg)9例与轻症组(PaO2≥60 mm Hg)7例;另设健康对照组8例。结果治疗前后(发病第7天、14天采血样),各组IFN-γ,IL-6,IL-8,TNF-α等水平变化无统计学意义(P>0.05),各组间差异亦无统计学意义(P>0.05)。治疗前重症组TGF-β1水平较轻症组明显增加,差异有统计学意义(P<0.05),治疗后重症组TGF-β1仍维持较高水平,与治疗前相比差异无统计学意义(P>0.05),部分病例在恢复期(体温正常,气短减轻,血氧正常)发现肺纤维化征象。CRP水平的升高与低淋巴细胞血症在重症组和轻症组均常见,但重症组治疗前淋巴细胞总数更低,与轻症组相比差异有统计学意义(P<0.05);治疗后,两组低淋巴细胞血症明显改善,与治疗前相比差异均有统计学意义(P<0.05),CRP水平的明显下降仅见于轻症组,差异有统计学意义(P<0.05)。所有幸存者的CRP水平与淋巴细胞总数均迅速地恢复至正常,相反,治疗后CRP水平无明显下降者及淋巴细胞总数无明显上升者预后较差。结论通过对血浆相关细胞因子水平(IFN-γ,IL-6,IL-8,TNF-α,TGF-β1)的测定发现,合并肺炎的甲型H1N1流感病例血浆中,只有TGF-β1是过度产生的;其他细胞因子水平无变化的原因可能与大部分入选病例使用糖皮质激素有关,糖皮质激素可抑制机体针对甲型H1N1流感病毒感染的免疫反应。治疗前血中TGF-β1水平、T淋巴细胞总数与疾病严重性有关,可能对疾病严重性有预测作用。血中升高的TGF-β1水平与甲型H1N1流感合并肺炎患者肺纤维化的发生之间的关系仍需进一步研究。展开更多
基金This work was financially supported by the National Key Research and Development Program of China(2017YFD0500101)the Fundamental Research Funds for the Central Universities(Y0201900459).
文摘Influenza viruses are major respiratory pathogens known to infect human and a variety of animals and are widely prevalent worldwide.Genome structure of influenza D virus(IDV)is identical to that of influenza C virus(ICV),and phylogenetic analyses suggest that IDV and ICV share a common ancestry and high homology.To date,the prevalence of ICV and IDV in China is unclear,but these viruses represent a potential threat to public health due to cross-species transmission and zoonotic potential.To efficiently monitor ICV and IDV,it is necessary to establish a dual detection method to understand their prevalence and conduct in-depth research.A duplex real-time PCR method for the simultaneous detection of ICV and IDV was developed.TaqMan fluorescent probes and specific primers targeting NP gene of ICV and PB1 gene of IDV were designed.This method exhibited good specificity and sensitivity,and the detection limit reached 1 × 10^(1) copies/pL of plasmid standards of each pathogen.Thirty-one clinical swine samples and 10 clinical cattle samples were analyzed using this method.One positive sample of IDV was detected,and the accuracy of clinical test results was verified by conventional PCR and DNA sequencing.The duplex real-time PCR detection method represents a sensitive and specific tool to detect IG/and IDV,It provides technical support for virus research and clinical diagnosis of ICV and IDV.This information will benefit animal and human health.
文摘C-type lectin receptors (CLRs) are representative pattern recognition receptors that recognize microbial polysaccharides expressed on antigen-presenting cells. In the present study, we carried out further detailed analysis on the involvement of Dectin-2, a CLR that senses high mannose polysaccharide, in innate immune responses induced by influenza virus hemagglutinin (HA). Treatment of HA with periodate or PNGase F induced lower interleukin (IL)-12p40 secretion by conventional dendritic cells (DCs) compared with the untreated group. In contrast, treatment with O-glycosidase did not affect cytokine production. Green fluorescent protein expression in canonical Dectin-2-transducing cells was approximately 3% - 12% following HA stimulation, except with the A/H1N1pdm09 subtype HA. This expression was markedly reduced in cells possessing mutated amino acids in the carbohydrate recognition domain of Dectin-2, especially following stimulation with HA derived from the A/H3N2 subtype. Interferon (IFN)-α production from CD11c<sup>+</sup>Siglec-H<sup>+</sup>PDCA-1<sup>+</sup> plasmacytoid DCs was significantly increased in Dectin-2 knockout mice compared with wild-type mice upon stimulation with HA except for the B/Yamagata lineage HA. These results suggested that Dectin-2 is involved in initiating inflammatory responses via mannose polysaccharide on HA. However, other mechanisms may function in the antiviral response, including the type I IFN axis.
文摘Influenza C virus, a member of the Orthomyxoviridae family, causes flu-like disease but typically only with mild symptoms. Humans are the main reservoir of the virus, but it also infects pigs and dogs. Very recently, influenza C-like viruses were isolated from pigs and cattle that differ from classical influenza C virus and might constitute a new influenza virus genus. Influenza C virus is unique since it contains only one spike protein, the hemagglu- tinin-esterase-fusion glycoprotein HEF that possesses receptor binding, receptor destroying and membrane fusion activities, thus combining the functions of Hemaggiutinin （HA） and Neuraminidase （NA） of influenza A and B viruses. Here we briefly review the epidemiology and pathology of the virus and the morphology of virus particles and their genome. The main focus is on the structure of the HEF protein as well as on its co- and post- translational modification, such as N-glycosylation, disulfide bond formation, S-acylation and proteolytic cleavage into HEF1 and HEF2 subunits. Finally, we describe the functions of HEF： receptor binding, esterase activity and membrane fusion.
文摘目的探讨合并肺炎的甲型H1N1流感患者血浆中相关细胞因子、C反应蛋白(CRP)及T淋巴细胞计数在病程中的变化特征,为临床早期诊断与治疗提供参考。方法检测16例合并肺炎的住院甲型H1N1流感患者血浆中相关细胞因子[γ干扰素(IFN-γ),白细胞介素6(IL-6),白细胞介素8(IL-8),肿瘤坏死因子-α(TNF-α),转化生长因子-β1(TGF-β1)]水平、CRP及T淋巴细胞计数的变化。根据患者入院时血气分析中动脉血氧分压(PaO2)水平,分为重症组(PaO2<60 mm Hg)9例与轻症组(PaO2≥60 mm Hg)7例;另设健康对照组8例。结果治疗前后(发病第7天、14天采血样),各组IFN-γ,IL-6,IL-8,TNF-α等水平变化无统计学意义(P>0.05),各组间差异亦无统计学意义(P>0.05)。治疗前重症组TGF-β1水平较轻症组明显增加,差异有统计学意义(P<0.05),治疗后重症组TGF-β1仍维持较高水平,与治疗前相比差异无统计学意义(P>0.05),部分病例在恢复期(体温正常,气短减轻,血氧正常)发现肺纤维化征象。CRP水平的升高与低淋巴细胞血症在重症组和轻症组均常见,但重症组治疗前淋巴细胞总数更低,与轻症组相比差异有统计学意义(P<0.05);治疗后,两组低淋巴细胞血症明显改善,与治疗前相比差异均有统计学意义(P<0.05),CRP水平的明显下降仅见于轻症组,差异有统计学意义(P<0.05)。所有幸存者的CRP水平与淋巴细胞总数均迅速地恢复至正常,相反,治疗后CRP水平无明显下降者及淋巴细胞总数无明显上升者预后较差。结论通过对血浆相关细胞因子水平(IFN-γ,IL-6,IL-8,TNF-α,TGF-β1)的测定发现,合并肺炎的甲型H1N1流感病例血浆中,只有TGF-β1是过度产生的;其他细胞因子水平无变化的原因可能与大部分入选病例使用糖皮质激素有关,糖皮质激素可抑制机体针对甲型H1N1流感病毒感染的免疫反应。治疗前血中TGF-β1水平、T淋巴细胞总数与疾病严重性有关,可能对疾病严重性有预测作用。血中升高的TGF-β1水平与甲型H1N1流感合并肺炎患者肺纤维化的发生之间的关系仍需进一步研究。
