轮状病毒肠炎肠外器官损伤的临床研究

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人轮状病毒疫苗研究进展

轮状病毒(RV)是引起婴幼儿和幼龄动物腹泻的主要病原体,轮状病毒无特效药物进行治疗,只能通过疫苗免疫预防,因此,轮状病毒疫苗的合理应用在降低全世界轮状病毒性腹泻的发病率和死亡率中显得尤为重要。但目前商品化的口服减毒活疫苗存在潜在的安全性问题以及在中低收入国家免疫效力不高的缺陷,需要研发更加安全、高效的疫苗来防控轮状病毒性腹泻。近年来,随着轮状病毒研究的不断深入,鉴定出了新的轮状病毒血清型,并且有4种轮状病毒疫苗通过世界卫生组织的使用资格预审,还有一些新型疫苗正处于研发阶段。本文根据各国学者的研究对轮状病毒疫苗研究进展做一综述,为进一步研究提供一定的参考。     

对一步夹心法轮状病毒单克隆抗体酶标试剂盒的评价

以一步夹心法轮状病毒单克隆抗体酶标试剂盒及聚丙烯酰胺凝胶电泳对253份粪样进行检测,结果显示试剂盒敏感度和特异度分别为96.36％和96.28％;阳性预示值和阴性预示值分别为98.15％和92.45％;试剂盒批内和批间变异系数分别为4.65％和8.06％。表明本试剂盒敏感性和特异性均好,且较稳定,适用于临床快速诊断。     

河北卢龙地区猪C组轮状病毒流行状况和VP6基因多样性分析

目的 了解GCRV在我国卢龙地区猪中流行状况和VP6蛋白编码基因的多样性特点,为猪GCRV的深入研究提供依据.方法 采集2007年冬至2008年春河北卢龙地区腹泻和正常猪粪便标本共793份.采用巢式反转录-聚合酶链反应(Nested RT-PCR)的方法对GCRV进行检测,并对测定序列进行同源性和系统进化分析.结果 在793份粪便标本中,GCRV阳性率为16.65％,卢龙地区猪GCRV毒株间同源性差异较大.核苷酸进化树表明,猪GCRV多样性显著.由氨基酸进化分析可知,同一宿主的GCRV氨基酸序列亲缘关系更近.结论 2007-2008年冬春两季,C组轮状病毒在我国卢龙地区猪中感染率较高.VP6基因多样性广泛存在.实验提供的数据为进一步研究猪GCRV的分子流行特征提供了基础.     

轮状病毒感染性脓毒症患儿血清CRP、免疫球蛋白水平变化及其与心肌酶谱的相关性研究

目的：分析轮状病毒感染性脓毒症患儿血清CRP、免疫球蛋白水平变化及其与心肌酶谱的关系。方法选择在本院接受住院治疗的56例轮状病毒感染性脓毒症患儿作为观察组,选择同期在本院注射疫苗的56例健康小儿作为对照组,比较两组研究对象的血清CRP、免疫球蛋白水平及心肌酶谱指标值差异,分析血清CRP、免疫球蛋白水平与心肌酶谱相关性。结果(1)观察组患儿血清CRP水平显著高于对照组(P<0.05),但其血清IgG、IgM、IgA等免疫球蛋白水平均显著低于对照组(P<0.05);(2)观察组患儿的血清高敏心肌肌钙蛋白(hs-cTnT)、肌酸激酶(CK)、肌酸激酶同工酶(CK-MB)等心肌酶谱指标值明显高于对照组(P<0.05);(3)血清CRP水平与hs-cTnT、CK、CK-MB呈正相关(P<0.05),IgG、IgM、IgA水平与hs-cTnT、CK、CK-MB呈负相关(P<0.05)。结论轮状病毒感染性脓毒症患儿血清CRP、心肌酶谱水平升高,免疫球蛋白水平降低,且心肌酶谱指标值与血清CRP、免疫球蛋白含量具有相关性。     

Role of myeloid differentiation factor 88 in Rhesus rotavirus-induced biliary atresia

Background

Biliary atresia (BA) is a unique neonatal disease resulting from inflammatory and fibrosing obstruction of the extrahepatic biliary tree. Previous studies have demonstrated the critical role of innate immunity and the Th1 response to activated inflammatory cells and overexpressed cytokines in the pathogenesis of BA. Myeloid differentiation factor 88 (MyD88) is a critical adaptor molecule that has been shown to play a crucial role in immunity. We investigated the role of MyD88 in the inflammatory response and development of cholangiopathy in murine BA.

Methods

MyD88 knockout (MyD88^−/−) and wild-type (WT) BALB/c pups were injected with Rhesus rotavirus or saline on day 1 of life. The mice were monitored for clinical symptoms of BA, including jaundice, acholic stools, bilirubinuria, and death. The liver and extrahepatic bile ducts were harvested for histologic evaluation and the quantification of viral content, determination of cytokine expression, and detection of inflammatory cells.

Results

Rhesus rotavirus infection produced symptoms in 100% of both MyD88^−/− and WT pups, with survival of 18% of WT and 0% of MyD88^−/− mice. Histologic analysis demonstrated bile duct obstruction in both MyD88^−/− and WT mice. Viral titers obtained 7 d after infection and expression of interferon-γ and tumor necrosis factor-α at day 3, 5, 8, and 12 after infection revealed no significant differences between the WT and MyD88^−/− mice. Flow cytometry demonstrated similar levels of activated CD8+ T cells and natural killer cells.

Conclusions

The pathogenesis of murine BA is independent of the MyD88 signaling inflammatory pathway, suggesting alternative mechanisms are crucial in the induction of the model.     

2006年至2008年上海市住院腹泻患儿A组轮状病毒的分子流行病学调查

目的 分析上海地区住院腹泻患儿A组轮状病毒(RV)基因型别、流行季节及年龄分布,以了解本地区A组RV的分子流行病学动态变化特征,为婴幼儿腹泻的预防和控制提供理论依据.方法 2006年1月至2008年12月共收集来自复旦大学附属儿科医院5岁以下腹泻患儿的5176份粪便标本.抽取其中RV抗原阳性标本380份,采用套式多重RT-PCR法进行RV的基因分型.结果 2006-2008年RV腹泻主要的流行季节是10-12月份,＜3岁的患儿占全部患儿的96.8％.380份粪标本中,222份为G3型,占58.4％,41份为G9型,占10.8％.3年间G1型、G2型均少见,G混合型以G3和G9型的混合为主.2006年和2008年均以P[8]型的流行为主,分别占64.6％(53/82)和46.8％(58/124).2007年以P[4]型为主,占38.5％(67/174).P[6]和P[9]型所占比例较低,P混合型以P[8]和P[4]型的混合为主.G未分型和P未分型在3年间均呈上升趋势.P[8]G3型(20.5％)是上海地区2006-2008年间最主要的A组RV流行株,其次包括P[4]G3型及P[m]G3型.结论 2006-2008年上海地区A组RV显示了新的分子流行病学变化特征,包括主要流行型别的改变,流行型别更趋于多样化.     

更昔洛韦联合思密达治疗轮状病毒肠炎56例效果分析

将收治的轮状病毒肠炎婴幼儿120例随机分为2组,对照组64例,使用更昔洛韦5～10mg/(kg·d)静脉滴注;观察组56例,更昔洛韦5～10 mg/(kg·d)静脉滴注,同时口服思密达,每次1/3包,3次/d。治疗后,对照组和观察组总有效率分别为62.50%(40/64)和89.29%(50/56),差异有统计学意义(P<0.05)。表明更昔洛韦联合思密达治疗婴幼儿轮状病毒肠炎疗效显著,值得推广。     

Protein deficiency reduces efficacy of oral attenuated human rotavirus vaccine in a human infant fecal microbiota transplanted gnotobiotic pig model

BackgroundLow efficacy of rotavirus (RV) vaccines in developing African and Asian countries, where malnutrition is prevalent, remains a major concern and a challenge for global health.MethodsTo understand the effects of protein malnutrition on RV vaccine efficacy, we elucidated the innate, T cell and cytokine immune responses to attenuated human RV (AttHRV) vaccine and virulent human RV (VirHRV) challenge in germ-free (GF) pigs or human infant fecal microbiota (HIFM) transplanted gnotobiotic (Gn) pigs fed protein-deficient or -sufficient bovine milk diets. We also analyzed serum levels of tryptophan (TRP), a predictor of malnutrition, and kynurenine (KYN).ResultsProtein-deficient pigs vaccinated with oral AttHRV vaccine had lower protection rates against diarrhea post-VirHRV challenge and significantly increased fecal virus shedding titers (HIFM transplanted but not GF pigs) compared with their protein-sufficient counterparts. Reduced vaccine efficacy in protein-deficient pigs coincided with altered serum IFN-α, TNF-α, IL-12 and IFN-γ responses to oral AttHRV vaccine and the suppression of multiple innate immune parameters and HRV-specific IFN-γ producing T cells post-challenge. In protein-deficient HIFM transplanted pigs, decreased serum KYN, but not TRP levels were observed throughout the experiment, suggesting an association between the altered TRP metabolism and immune responses.ConclusionCollectively, our findings confirm the negative effects of protein deficiency, which were exacerbated in the HIFM transplanted pigs, on innate, T cell and cytokine immune responses to HRV and on vaccine efficacy, as well as on TRP-KYN metabolism.