Immunisation with the BCG and DTPw vaccines induces different programs of trained immunity in mice

In addition to providing pathogen-specific immunity, vaccines can also confer nonspecific effects (NSEs) on mortality and morbidity unrelated to the targeted disease. Immunisation with live vaccines, such as the BCG vaccine, has generally been associated with significantly reduced all-cause infant mortality. In contrast, some inactivated vaccines, such as the diphtheria, tetanus, whole-cell pertussis (DTPw) vaccine, have been controversially associated with increased all-cause mortality especially in female infants in high-mortality settings. The NSEs associated with BCG have been attributed, in part, to the induction of trained immunity, an epigenetic and metabolic reprograming of innate immune cells, increasing their responsiveness to subsequent microbial encounters. Whether non-live vaccines such as DTPw induce trained immunity is currently poorly understood. Here, we report that immunisation of mice with DTPw induced a unique program of trained immunity in comparison to BCG immunised mice. Altered monocyte and DC cytokine responses were evident in DTPw immunised mice even months after vaccination. Furthermore, splenic cDCs from DTPw immunised mice had altered chromatin accessibility at loci involved in immunity and metabolism, suggesting that these changes were epigenetically mediated. Interestingly, changing the order in which the BCG and DTPw vaccines were co-administered to mice altered subsequent trained immune responses. Given these differences in trained immunity, we also assessed whether administration of these vaccines altered susceptibility to sepsis in two different mouse models. Immunisation with either BCG or a DTPw-containing vaccine prior to the induction of sepsis did not significantly alter survival. Further studies are now needed to more fully investigate the potential consequences of DTPw induced trained immunity in different contexts and to assess whether other non-live vaccines also induce similar changes.     

Development of an IgG-Fc fusion COVID-19 subunit vaccine,AKS-452

AKS-452 is a biologically-engineered vaccine comprising an Fc fusion protein of the SARS-CoV-2 viral spike protein receptor binding domain antigen (Ag) and human IgG1 Fc (SP/RBD-Fc) in clinical development for the induction and augmentation of neutralizing IgG titers against SARS-CoV-2 viral infection to address the COVID-19 pandemic. The Fc moiety is designed to enhance immunogenicity by increasing uptake via Fc-receptors (FcγR) on Ag-presenting cells (APCs) and prolonging exposure due to neonatal Fc receptor (FcRn) recycling. AKS-452 induced approximately 20-fold greater neutralizing IgG titers in mice relative to those induced by SP/RBD without the Fc moiety and induced comparable long-term neutralizing titers with a single dose vs. two doses. To further enhance immunogenicity, AKS-452 was evaluated in formulations containing a panel of adjuvants in which the water-in-oil adjuvant, Montanide™ ISA 720, enhanced neutralizing IgG titers by approximately 7-fold after one and two doses in mice, including the neutralization of live SARS-CoV-2 virus infection of VERO-E6 cells. Furthermore, ISA 720-adjuvanted AKS-452 was immunogenic in rabbits and non-human primates (NHPs) and protected from infection and clinical symptoms with live SARS-CoV-2 virus in NHPs (USA-WA1/2020 viral strain) and the K18 human ACE2-trangenic (K18-huACE2-Tg) mouse (South African B.1.351 viral variant). These preclinical studies support the initiation of Phase I clinical studies with adjuvanted AKS-452 with the expectation that this room-temperature stable, Fc-fusion subunit vaccine can be rapidly and inexpensively manufactured to provide billions of doses per year especially in regions where the cold-chain is difficult to maintain.     

极速实时荧光聚合酶链反应与常规方法对新型布尼亚病毒检测的评价

目的探讨极速实时荧光聚合酶链反应(polymerase chain reaction,PCR)、实时荧光PCR、酶联免疫吸附测定(enzyme-linked immunosorbent assay,ELISA)和胶体金免疫层析法(gold immunochromatography assay,GICA)4种方法检测新型布尼亚病毒的特异度和灵敏度,为发热伴血小板减少综合征的早期诊断提供依据。方法采集2017年6月1日至9月30日山东大学附属济南市传染病医院86例临床诊断为发热伴血小板减少综合征患者的血清样本,分别应用极速实时荧光PCR、实时荧光PCR、ELISA和GICA 4种方法进行检测。统计学分析采用χ^2检验。结果86份患者血清标本中,极速实时荧光PCR、实时荧光PCR、IgM-ELISA、IgG-ELISA、IgM-GICA、IgG-GICA的新型布尼亚病毒阳性分别为82份(95.34%)、79份(91.86%)、41份(47.67%)、8份(9.3%)、19份(22.09%)和3份(3.49%)。极速实时荧光PCR特异度为100%,灵敏度达到1×103拷贝/mL,3次重复扩增试验显示其Ct值变异系数均<2%。在发热伴血小板减少综合征进展的1期、2期、3期病程中,极速实时荧光PCR的阳性检出率为41份(97.62%)、34份(94.44%)、7份(87.50%),实时荧光PCR的阳性检出率为39份(92.86%)、33份(91.67%)、7份(87.50%),在1期和2期两个病程,极速实时荧光PCR阳性检出率略高;IgM-ELISA阳性检出率从1期(28.57%)到3期(87.50%)显著增高,2期、3期与1期相比,差异均有统计学意义(χ^2=8.347、7.561,均P<0.01);IgM-GICA的阳性检出率从1期(14.29%)到2期(33.33%)也有增高,差异有统计学意义(χ^2=3.962,P<0.05),但与其他方法相比,其检出率偏低。1期,实时荧光PCR阳性检出率显著高于ELISA(IgM和IgG)和GICA(IgM和IgG),差异均有统计学意义(χ^2=33.740、55.080、49.010、64.340,均P<0.01)。2期,实时荧光PCR的阳性检出率高于ELISA(IgM和IgG)和GICA(IgM和IgG),差异均有统计学意义(χ^2=7.700、46.720、23.700、50.630,均P<0.01)。3期,极速实时荧光PCR、实时荧光PCR和IgM-ELISA表现出同样高的阳性检出率,远高于IgG-ELISA和GICA(IgM和IgG)。实时荧光PCR阳性检出率和IgG-ELISA、IgM-GICA、IgG-GICA之间差异均有统计学意义(均χ^2=6.250,P<0.05)。结论极速实时荧光PCR在新型布尼亚病毒的早期检测中有更高的灵敏度和特异度,且重复性好、稳定度高,与传统实时荧光PCR相比大大缩短了扩增时间,对发热伴血小板减少综合征的早期快速诊断具有重要价值。     

广州地区无偿献血人群人类疱疹病毒8型血清流行病学调查

目的：了解广州地区无偿献血者HHV-8的感染情况，为制定预防策略提供依据。方法：采用ELISA法检测3135名无偿献血者血浆HHV-8IgG抗体。结果：3135名献血者中6名血浆标本被检出HHV-8IgG抗体阳性，均为汉族、男性献血员，总阳性率为0．19％。不同年龄和性别组HHV-8感染率差异无统计学意义。结论：广州地区无偿献血人群HHV-8的感染率较低。     

酶联免疫吸附试验、间接荧光抗体试验、间接免疫过氧化物酶染色试验诊断人体旋毛虫病的初步研究

用ELISA、IFA和IIP试验检测11例旋毛虫病人血清特异性抗体,阳性率分别为72.72％、81.82％和81.82%。它们之间无统计学差异,3项试验结果间存在良好一致性。 同时检测了30份健康献血员血清和20例其他寄生虫病人血清(包括华支睾吸虫病、四川肺吸虫病、日本血吸虫病、包虫病和阿米巴肝脓肿),旋毛虫病人组的ELISA、IFA和IIP阳性率明显为高。 由于3项免疫学试验均具有较好的特异性和灵敏性,故可以单独或联合用于人体旋毛虫病的诊断和流行病学调查。     

脊髓血管畸形血管内皮生长因子在脑脊液的表达

目的探讨脊髓血管畸形是否存在血管内皮生长因子(VEGF)表达,及其表达与临床特征之间是否存在相关性。方法在手术中留取56例脊髓血管畸形的脑脊液标本,其中动静脉畸形(SCAVM)23例,硬脊膜动静脉瘘(SDAVF)19例,海绵状血管瘤(CM)14例;以我院12例蛛网膜下腔阻滞病人脑脊液作为对照组,分别通过酶联免疫吸附方法(ELISA)测定脊髓血管畸形脑脊液中VEGF含量。结果SCAVM脑脊液中VEGF浓度为(277±66)pg/ml、SDAVF为(318±54)pg/ml、CM为(146±32)pg/ml均高于正常对照组(123±27)pg/ml。术前栓塞和出血均可导致脑脊液VEGF升高。结论VEGF与脊髓血管畸形的发生、发展存在一定关系,出血和栓塞均可影响VEGF的表达。     

两种清除法测定低密度脂蛋白胆固醇的临床评价

目的对表面活性剂清除法 (SUR法 )和过氧化氢酶清除法 (CAT法 )两种低密度脂蛋白胆固醇 (LDL C)均相测定法进行临床评价。方法将上述两种方法与聚乙烯硫酸沉淀法 (PVS法 )进行比较 ,分析各自方法的精密度、准确性、特异性和干扰因素。结果两种清除法与PVS法 (X)具有良好的相关性 ,SUR法 (Y1) :Y1=0 .9311X +0 .10 2 2 ,r =0 .980 1;CAT法 (Y2 ) :Y2 =0 .94 0 1X +0 .0 991,r=0 .9832。高、中、低三种LDL C浓度混合血清所测定结果表明两种方法均具有良好的精密度 ,总CV值SUR法 3.4 5 - 3.89% ,CAT法 3.5 1- 3.99% ,均达到临床满意的程度。两法线性范围均较宽 (线性均至 8.2 2mmol/L) ,最低检测浓度均为 0 .12mmol/L ,平均回收率SUR法为 98.0 % ,CAT法为 97.6 %。TG <14 .2mmol/L ,Hb <5g/L ,HDL C <3.88mmol/L ,胆红素 <4 5 0 μmol/L对两法基本无影响。 结论两种LDL C清除法测定结果的准确度和精密度均符合临床要求 ,适宜自动分析 ,值得在临床推广应用。     

四甲基联苯胺在ELISA和免疫斑点试验中的应用

本文以间接法ELISA检测轮状病毒特异性IgG为模型,对新底物四甲基联苯胺(TMB)与邻苯二胺(OPD)进行了比较研究,结果发现,TMB具有下列优点:①稳定性好;②敏感性高;③酶结合物和H_2O_2用量少。而且TMB又无致癌性,故是辣根过氧化酶较理想的底物。此外,还首次将TMB应用于免疫斑点试验,获得成功。     

Antibodies against saline-soluble components of skeletal muscle in myasthenia gravis

Summary Antibodies against phosphate-buffered-saline extracts (SE) of non-acetylcholine receptor (AChR) skeletal muscle antigens were found in patients with myasthenia gravis (MG). The antigenicity of SE was distributed in three fractions with molecular masses of over 200 kDa, 90–150 kDa and 7–14 kDa on gel filtration. These fractions shared common antigenicities. Further analysis of 90–150 kDa fractions on sodium dodecyl sulphate polyacrylamide gel electrophoresis showed five major bands, ranging from 105 kDa to 275 kDa. The antibodies against SE were detected in 52% (58/112) of the MG patients; incidence and titres were higher in the thymoma group (n=21; 90% and 0.872 respectively) than in the non-thymoma group (n=91; 43% and 0.200, P<0.001). In patients without a thymoma, these antibodies were frequently observed in late-onset disease and the severe generalized form (P<0.01). In 4 of 7 ocular MG patients without anti-AChR antibodies, low but appreciable levels of anti-SE antibodies were found. In 73% (11/15) of generalized MG patients treated with prednisolone and thymectomy, anti-SE antibody titres changed in association with those of anti-AChR antibodies and with the clinical course. Both antibody titres increased synchronously in patients who developed crises.