酶标法相对定量检测Vero细胞疫苗中宿主细胞蛋白

目的　建立定量检测Vero细胞疫苗中宿主细胞蛋白 (hostcellprotein ,HCP)的方法 ,并用该方法检测Vero细胞乙脑疫苗中HCP含量。方法　模拟Vero细胞疫苗生产工艺 ,制备Vero细胞HCP及其免疫血清 ,经过DEAEProteinASepharoseCL -4B亲和层析 ,制备纯化的抗Vero细胞HCPIgG。通过对检测条件的优化 ,确立了酶标法相对定量检测Vero细胞疫苗中宿主细胞蛋白的方法 ,并用该方法对Vero细胞乙脑疫苗的收获物、中间产品及纯化样品收样前杂蛋白中HCP进行定量分析。结果　该方法可以检测Vero细胞疫苗加入保护剂前任何阶段产品中HCP含量。结论　ELISA法可以相对定量检测Vero细胞HCP的含量。     

应用CHO细胞法检测百日咳疫苗中的残余毒性

根据百日咳毒素（PT）能特异地使中华地鼠卵巢细胞（CHO）聚集的性质，采用CHO细胞分析法检测了18批全细胞百白破疫苗（DTPw）和12批无细胞百白破疫苗（DTPa）。存放于4℃的两种疫苗中，DTPw聚集CHO细胞滴度的几何均值（GMT）是30.79±2．316,DTPa不产生聚集、两种疫苗在37℃存放4周后，DTPw聚集滴度的GMT是948．09±1．598．DTPa是205．67±1．392。实验结果表明，百日咳疫苗存在明显的毒性逆转现象，与动物试验不一致。因此建议采用CHO方法检测百日咳疫苗中PT的毒性。     

细胞荧光转化灶法检测狂犬病病毒滴度

目的应用细胞荧光转化灶(fluorescence focus units assay,FFU)法检测狂犬病病毒滴度。方法将狂犬病病毒稀释后接种BSR细胞,培养22~24 h,用FITC标记的抗狂犬病病毒特异性抗体进行染色,计数病毒感染细胞的荧光灶数,计算病毒滴度。采用乳鼠半数致死量(median lethal dose,LD50)法和建立的方法分别测定14批狂犬病病毒滴度,分析两者间的相关性;取同一份病毒液,于不同时间点检测3次,每个时间点重复检测6次,验证方法的重复性;取3份滴度不同的病毒液,由2个操作者在不同时间重复测定3次,验证方法的中间精密性;将同一份病毒液按2倍梯度稀释,共9个稀释度,分别检测病毒滴度,重复测定3次,确定该方法的线性范围。应用建立的方法检测38批CTNCEC株狂犬病病毒滴度。结果乳鼠LD50法测定14批狂犬病病毒的-Lg LD50值范围为4.20~8.19,FFU法Lg FFU值范围为3.76~7.69,两种方法检测结果趋势相同,线性回归相关系数R-Sq(调整)=96.1%,存在良好的正相关性;同一个时间点检测6次及不同时间点检测3次的CV值均小于2.00%;两个操作者在不同时间重复测定3次的CV值均小于8.00%,两个操作者之间的检测结果差异无统计学意义(P>0.05);样品浓度与Lg FFU呈良好的线性关系,R-Sq(调整)=99.3%,线性范围为2.26~6.12。38批CTNCEC株狂犬病病毒滴度平均Lg FFU在3.63~7.69之间,SD值在0.021~0.57之间,CV值小于10.00%。结论建立的细胞FFU法准确性、重复性、中间精密度好,该方法可用于检测狂犬病病毒滴度。     

腮腺炎减毒活疫苗感染性滴度荧光定量RT-PCR检测方法的建立及验证

目的建立腮腺炎减毒活疫苗感染性滴度荧光定量RT-PCR检测方法,并进行验证。方法针对腮腺炎减毒活疫苗株S79血凝素(hemagglutinin,H)基因保守区域设计特异性引物和Taq Man荧光探针;以05008批腮腺炎减毒活疫苗S79株成品作为参考品,将参考品或供试品稀释后,接种于长成单层的Vero细胞中,采用低渗合并冻融法将细胞破碎,吸取上清,进行荧光定量RT-PCR。优化病毒感染时间,并对该方法的特异性、精密性及准确性进行验证。结果病毒感染的最佳时间为18 h;建立的荧光定量RT-PCR法只对腮腺炎减毒活疫苗具有特异性扩增,对灭活的腮腺炎减毒活疫苗、水痘病毒、狂犬病病毒、麻疹病毒、风疹病毒和Vero细胞均无扩增曲线出现;该方法检测4个浓度(1、1:5、1:52、1:53)样品6组数据的相对标准偏差(relative standard deviation,RSD)均5%,不同操作人员于不同日期检测4个浓度(1、1:5、1:52、1:53)样品的标准曲线回归方程R2均大于0.97,RSD均5%;该方法与细胞病变法测得的11批腮腺炎减毒活疫苗成品的病毒滴度值之差均≤0.2 Lg CCID50/ml,两组数据差异无统计学意义(P0.05)。结论建立的荧光定量PCR法检测腮腺炎减毒活疫苗感染性滴度特异性较强,精密性和准确性良好,且快速方便,可应用于企业生产过程中的内部质控。     

饲养细胞用于挽救濒死的珍稀贴壁细胞

目的挽救濒于死亡的珍稀贴壁细胞。方法将濒于死亡的RINm5F细胞接种到一定量体外培养的小鼠腹腔细胞中,经过一段时间的培养,待RINm5F细胞逐渐长成岛状时,传代并再连续添加2次饲养细胞培养后,传2代,冻存。结果濒于死亡的RINm5F细胞与饲养细胞共培养,随着时间的延长,细胞生长速度加快,饲养细胞逐渐死亡,再经2次与饲养细胞共培养,细胞已恢复正常生长,冻存后复苏生长状态良好。结论添加饲养细胞的方法可用于挽救濒于死亡的细胞。     

滤膜法与国标法用于微生物检测的比较研究

探讨了采用滤膜法与国标法(GB/T 4789.2-2003)在食品、化妆品等领域进行微生物检测的优缺点.微生物检测主要通过大肠杆茵、阴沟肠杆茵、金黄色葡萄球茵、绿脓杆菌的回收率以及活茵总数的检出结果和检出率来具体体现.结果表明,滤膜法在灵敏度、可靠性、检出率、活茵回收率等方面明显优于国标法,检验结果更加真实.     

CHO-K1细胞簇集法检测百日咳毒素毒性的优化及验证

目的对CHO-K1细胞簇集法检测百日咳毒素(pertussis toxin,PT)毒性进行优化及验证。方法以国家PT标准品为参考品,将PT标准品倍比稀释后与CHO-K1细胞混合培养,显微镜观察PT能引起CHO-K1细胞簇集的程度。对细胞浓度、孵育时间进行优化,并对方法的特异性、敏感度、重复性进行验证。结果方法的最佳细胞浓度为2.5×105个/ml,最佳孵育时间为24 h。只有PT活性成分能使CHO-K1细胞发生簇集,最低检测限为10 pg/ml;2名试验员6次检测结果表明,该方法重复性良好。结论 CHO-K1细胞簇集法可及时、准确地检测出生产过程中PT含量,适用于百日咳发酵过程监测。     

用于固定化酶和细胞的陶瓷载体

本文简述了酶和细胞的固定化方法及作为载体材料之一的陶瓷的一些特性。结合固定化酶和细胞的性质和应用情况,认为采用陶瓷载体具有一系列的优点。文中列举了采用陶瓷做载体的实例。认为陶瓷作为固定化酶和细胞的载体可促进固定化酶和细胞技术及生物反应器的发展。此外还指出这一领域尚有很多问题还需要深入地进行研究。     

感染性物质包装检测标准方法的研究

感染性物质运输安全与否关系到民众的健康与生命安全,目前相关机构也在不断的加强感染性物质运输的管理,并不断在完善管理体制。本文通过对感染性物质包装的相关要求进行分析研究,为感染性物质包装检测提供参考,规范感染性物质包装检测工作。另外,通过在实践检测工作中的相关经验就感染性物质包装检测中的液压试验方法进行了重点论述。     

微生物法生产丙烯酰胺固定化细胞的改性研究

以添加天然物质提高海藻酸钙的机械强度及酶活性，为实际生产应用提供了可能。     

Electrochemical Sensors for Detection of Markers on Tumor Cells

In recent years, the increasing incidence and mortality of cancer have inspired the development of accurate and rapid early diagnosis methods in order to successfully cure cancer; however, conventional methods used for detecting tumor cells, including histopathological and immunological methods, often involve complex operation processes, high analytical costs, and high false positive rates, in addition to requiring experienced personnel. With the rapid emergence of sensing techniques, electrochemical cytosensors have attracted wide attention in the field of tumor cell detection because of their advantages, such as their high sensitivity, simple equipment, and low cost. These cytosensors are not only able to differentiate tumor cells from normal cells, but can also allow targeted protein detection of tumor cells. In this review, the research achievements of various electrochemical cytosensors for tumor cell detection reported in the past five years are reviewed, including the structures, detection ranges, and detection limits of the cytosensors. Certain trends and prospects related to the electrochemical cytosensors are also discussed.     

Olaparib-Based Photoaffinity Probes for PARP-1 Detection in Living Cells

The poly-ADP-ribose polymerase (PARP) is a protein from the family of ADP-ribosyltransferases that catalyzes polyadenosine diphosphate ribose (ADPR) formation in order to attract the DNA repair machinery to sites of DNA damage. The inhibition of PARP activity by olaparib can cause cell death, which is of clinical relevance in some tumor types. This demonstrates that quantification of PARP activity in the context of living cells is of great importance. In this work, we present the design, synthesis and biological evaluation of photo-activatable affinity probes inspired by the olaparib molecule that are equipped with a diazirine for covalent attachment upon activation by UV light and a ligation handle for the addition of a reporter group of choice. SDS-PAGE, western blotting and label-free LC-MS/MS quantification analysis show that the probes target the PARP-1 protein and are selectively outcompeted by olaparib; this suggests that they bind in the same enzymatic pocket. Proteomics data are available via ProteomeXchange with identifier PXD018661.     

SPR-Based Detection of ASF Virus in Cells

African swine fever (ASF) is one of the most dangerous hemorrhagic infectious diseases that affect domestic and wild pigs. Currently, neither a vaccine nor effective treatments are available for this disease. As regards the degree of virulence, ASFV strains can be divided into high, moderate, or low virulence. The main detection methods are based on the use of the polymerase chain reaction (PCR). In order to prevent an uncontrolled spread of ASF, new on-site techniques that can enable the identification of an early-stage disease are needed. We have developed a specific immunological SPR-based assay for ASFV antigen detection directly in liquid samples. The developed assay allows us to detect the presence of ASFV at the dose of 10³ HAD₅₀/_mL.     

Comparison of FACS and PCR for Detection of BCMA-CAR-T Cells

Chimeric-antigen-receptor (CAR)-T-cell therapy is already widely used to treat patients who are relapsed or refractory to chemotherapy, antibodies, or stem-cell transplantation. Multiple myeloma still constitutes an incurable disease. CAR-T-cell therapy that targets BCMA (B-cell maturation antigen) is currently revolutionizing the treatment of those patients. To monitor and improve treatment outcomes, methods to detect CAR-T cells in human peripheral blood are highly desirable. In this study, three different detection reagents for staining BCMA-CAR-T cells by flow cytometry were compared. Moreover, a quantitative polymerase chain reaction (qPCR) to detect BCMA-CAR-T cells was established. By applying a cell-titration experiment of BCMA-CAR-T cells, both methods were compared head-to-head. In flow-cytometric analysis, the detection reagents used in this study could all detect BCMA-CAR-T cells at a similar level. The results of false-positive background staining differed as follows (standard deviation): the BCMA-detection reagent used on the control revealed a background staining of 0.04% (±0.02%), for the PE-labeled human BCMA peptide it was 0.25% (±0.06%) and for the polyclonal anti-human IgG antibody it was 7.2% (±9.2%). The ability to detect BCMA-CAR-T cells down to a concentration of 0.4% was similar for qPCR and flow cytometry. The qPCR could detect even lower concentrations (0.02–0.01%). In summary, BCMA-CAR-T-cell monitoring can be reliably performed by both flow cytometry and qPCR. In flow cytometry, reagents with low background staining should be preferred.     

A Real-Time,Plate-Based BRET Assay for Detection of cGMP in Primary Cells

Cyclic guanosine monophosphate (cGMP) is a second messenger involved in the regulation of numerous physiological processes. The modulation of cGMP is important in many diseases, but reliably assaying cGMP in live cells in a plate-based format with temporal resolution is challenging. The Förster/fluorescence resonance energy transfer (FRET)-based biosensor cGES-DE5 has a high temporal resolution and high selectivity for cGMP over cAMP, so we converted it to use bioluminescence resonance energy transfer (BRET), which is more compatible with plate-based assays. This BRET variant, called CYGYEL (cyclic GMP sensor using YFP-PDE5-Rluc8), was cloned into a lentiviral vector for use across different mammalian cell types. CYGYEL was characterised in HEK293T cells using the nitric oxide donor diethylamine NONOate (DEA), where it was shown to be dynamic, reversible, and able to detect cGMP with or without the use of phosphodiesterase inhibitors. In human primary vascular endothelial and smooth muscle cells, CYGYEL successfully detected cGMP mediated through either soluble or particulate guanylate cyclase using DEA or C-type natriuretic peptide, respectively. Notably, CYGYEL detected differences in kinetics and strength of signal both between ligands and between cell types. CYGYEL remained selective for cGMP over cAMP, but this selectivity was reduced compared to cGES-DE5. CYGYEL streamlines the process of cGMP detection in plate-based assays and can be used to detect cGMP activity across a range of cell types.     

Re-evaluation of Adhesive Fracture Energy

A model to evaluate the Energy Release Rate (ERR) of adhesives using the Double Cantilever Beam (DCB) specimen is described. The model accounts for the adhesive bond thickness and its material properties. The analysis, considered as an improvement to the built-in cantilever beam model, treats the adherend as a finite beam which is partly free and partly supported by an elastic foundation and the adhesive bond as a thin strip under prescribed displacement. The results show significant effect of the adhesive parameters on the total ERR and that the built-in cantilever model underestimates the ERR. In general, the contribution of the adhesive bond to the ERR increases for softer adhesives, shorter cracks and thicker bonds.     

红细胞自身抗体的检测及结果分析

目的分析红细胞自身抗体阳性患者的临床诊断,探讨红细胞自身抗体的临床意义。方法采用微柱凝胶抗球蛋白试验,筛检和鉴定患者红细胞血型不规则抗体,根据抗体是否凝集其自身红细胞,鉴别同种抗体或自身抗体;对鉴定存在红细胞自身抗体的患者,进行红细胞直接抗球蛋白试验,并分析其临床诊断。结果在46000名检测红细胞血型不规则抗体的患者中,检出23名红细胞自身抗体阳性,其中红细胞直接抗球蛋白试验阳性者13名。在23名红细胞自身抗体阳性者中,临床诊断为自身免疫溶血性疾病6名,系统性红斑狼疮5名,Evans综合征2名,自身免疫性肝炎2名,药物性急性自身免疫溶血性贫血1名,过敏性紫癜性肾炎1名,Ⅰ型糖尿病酮症酸中毒1名,溃疡性结肠炎1名,4名未检出与自身免疫相关。结论红细胞自身抗体可出现于多种自身免疫性疾病或与自身免疫相关疾病患者的血浆中,检测红细胞自身抗体对自身免疫性疾病的诊断及治疗有参考意义。     

融合表达IL-2和EGFP逆转录病毒载体的构建

目的构建融合表达IL-2和EGFP报告基因的逆转录病毒载体。方法设计载体pRevTet-On和pEGFP-C1的接头序列,经酶切连接重组为过渡载体pRevEGFP-C1,同时对质粒pBV220-IL-2和pEGFP-C1进行酶切,连接重组为过渡载体pEGFP-C1-IL-2。分别酶切质粒pRevEGFP-C1和pEGFP-C1-IL-2,琼脂糖凝胶电泳回收目的片段IL-2,并将其连接到pRevEGFP-C1的多克隆位点(MCS)中,转化至E.coliDH5α进行扩增,提取质粒DNA获得重组体pRevEGFP-C1-IL-2。结果经分析鉴定,所构建的重组载体pRevEGFP-C1-IL-2完全正确。结论已成功地构建了融合表达IL-2和EGFP的逆转录病毒载体pRevEG-FP-C1-IL-2。     

一种检测环境样品和细胞中肼的香豆素类比率型荧光探针

以香豆素为荧光团,4-溴丁酰基为识别基团,设计合成了一种比率型肼荧光探针COCB。其结构通过1HNMR、13CNMR和HRMS确证。肼对探针COCB中溴代丁酰基的选择性脱保护使分子内电荷转移(ICT)过程恢复；COCB在 420 nm 处蓝色荧光衰减,而在 480 nm 处青色荧光增强,实现了对肼的比率检测。COCB对肼表现出高选择性、高灵敏度和强抗干扰能力,并能在较宽的线性范围(0~250 μmol/L)和pH范围(6~11)内检测肼,检出限低至0.15μmol/L。此外,COCB合成简便,细胞毒性较低,已成功用于实际水样、土壤以及活细胞中肼的检测。