Clinical value of chemiluminescence method for detection of antinuclear antibody profiles

BACKGROUND Antinuclear antibodies(ANAs)are crucial in diagnosing autoimmune diseases,mainly systemic lupus erythematosus(SLE).This study aimed to compare the performance of chemiluminescence assay(CLIA)and line immunoassay(LIA)in detecting ANAs in patients with autoimmune diseases,evaluate their diagnostic accuracy for SLE,and develop a novel diagnostic model using CLIA-detected antibodies for SLE.Specimens from patients with autoimmune diseases and physical examination specimens were collected to parallel detect specific antibodies.Individual antibodies'diagnostic performance and a model combining multiple antibodies were assessed.The findings provide valuable insights into improving the diagnosis of SLE through innovative approaches.AIM To compare the performance of CLIA and LIA in detecting ANAs in patients with autoimmune diseases,assess their accuracy for SLE,and develop a novel diagnostic model using CLIA-detected antibodies for SLE.METHODS Specimens have been obtained from 270 patients with clinically diagnosed autoimmune disorders,as well as 130 physical examination specimens.After that,parallel detection of anti-double-stranded DNA(dsDNA)antibody,anti-histone(Histone)antibody,anti-nucleosome(Nuc)antibody,anti-Smith(Sm)antibody,anti-ribosomal P protein(Rib-P)antibody,anti-sicca syndrome A(Ro60)antibody,anti-sicca syndrome A(Ro52)antibody,anti-sicca syndrome(SSB)antibody,anticentromere protein B(Cenp-B)antibody,anti-DNA topoisomerase 1(Scl-70)antibody,anti-histidyl tRNA synthetase(Jo-1)antibody,and anti-mitochondrial M2(AMA-M2)antibody was performed using CLIA and LIA.The detection rates,compliance rates,and diagnostic performance for SLE were compared between the two methodologies,followed by developing a novel diagnostic model for SLE.RESULTS CLIA and LIA exhibited essentially comparable detection rates for anti-dsDNA antibody,anti-Histone antibody,anti-Nuc antibody,anti-Sm antibody,anti-Rib-P antibody,anti-Ro60 antibody,anti-Ro52 antibody,anti-SSB antibody,anti-Cenp-B antibody,anti-DNAScl-70 antibody,anti-Jo-1 antibody and anti-AMA-M2 antibody(P>0.05).The two methods displayed identical results for the detection of anti-dsDNA antibody,anti-Histone antibody,anti-Nuc antibody,anti-Sm antibody,anti-Ro60 antibody,anti-Ro52 antibody,anti-SSB antibody,anti-Cenp-B antibody,anti-Scl-70 antibody,and anti-AMA-M2 antibody(Kappa>0.7,P<0.05),but showed a moderate agreement for the detection of anti-Rib-P antibody and anti-Jo-1 antibody(Kappa=0.671 and 0.665;P<0.05).In addition,the diagnostic performance of these antibodies detected by both methods was similar for SLE.The diagnostic model's area under the curve values,sensitivity,and specificity,including an anti-dsDNA antibody and an anti-Ro60 antibody detected by CLIA,were 0.997,0.962,and 0.978,respectively.These values were higher than the diagnostic performance of individual antibodies.CONCLUSION CLIA and LIA demonstrated excellent overall consistency in detecting ANA profiles.A diagnostic model based on CLIA-detected antibodies can successfully contribute to developing a novel technique for detecting SLE.

E-选择素在胚胎着床过程中小鼠子宫内膜的表达规律

目的:研究E-selectin在胚胎着床及早期分化中的作用。方法:用RT-PCR、Immunoblot、Western bolt法检测小鼠 胚胎着床前后蜕膜组织E-seleetin的表达。结果:E-选择素在孕4天的小鼠子宫内膜中的表达出现升高,第5天达到峰值,随后 妊娠第6、第7天E-selectin蛋白的表达则逐渐下降至正常水平。结论:提示E-选择素可能参与了胚胎着床过程。

Seroepidemiology of Helicobacter pylori infection in elderly people in the Beijing region, China

AIM: To investigate seroepidemiology of cagA+ and vacA+ strains of Helicobacter pylori (H. pylori) in an elderly population in Beijing and to determine risk factors for seropositivity.

Immunoproteome analysis of soluble and membrane proteins of Shigella flexneri 2457T

AIM: To profile the immunogenic proteins of Shigella flexneri (S. flexneri) expressed during human infection using a proteomic approach. METHODS: Soluble and membrane protein extractions of S. flexneri 2457T were separated by two-dimensional gel electrophoresis (2-DE). Proteins were transferred to PVDF membrane and immunoblotted with sera from shigellosis patients. Reactive protein spots were matched to Coomassie stained gels run in parallel, cut out and trypsin digested. Matrix-assisted laser desorption/ionization time of flight-mass spectrometry (MALDI-TOF-MS) was used to determine the peptide mass fingerprints, which were searched in the MASCOT database to identify the protein. RESULTS: A total of 8 immunoreactive proteins were successfully identified from the Coomassie stained gels in three repeats. Six of these proteins have not previously been reported as immunogenic in S. flexneri. These proteins could be potential candidates for vaccine or attenuation studies. CONCLUSION: Soluble and membrane proteins of S. flexneri 2457T have been screened by 2-DE and immunoblotting with sera from shigellosis patients. Eight proteins are identified as immunogenic.

A Comparative Study on Detection of the Expression of Alternative Oxidase in Tobacco Callus with the Monoclonal Antibody Against Alternative Oxidase and Antibody Against-Synthetic Polypeptide Antibody

从经过不同温度处理的烟草 (NicotianarusticaL .)愈伤组织中提取并纯化线粒体蛋白 ,分别与交替氧化酶的单克隆抗体和抗合成多肽抗体进行免疫杂交。结果表明 :交替氧化酶的含量随温度的下降而显著上升 ;单克隆抗体的特异性较高于抗合成多肽抗体 ,但后者与交替氧化酶同样有良好的亲和性。因此 ,用合成多肽方法制备的抗体可以用于交替氧化酶的研究中。

Serological diagnosis of Epstein-Barr virus infection: Problems and solutions

Serological tests for antibodies specific for Epstein-Barr virus(EBV) antigens are frequently used to define infection status and for the differential diagnosis of other pathogens responsible for mononucleosis syndrome. Using only three parameters [viral capsid antigen(VCA) Ig G, VCA Ig M and EBV nuclear antigen(EBNA)-1 Ig G],it is normally possible to distinguish acute from past infection: the presence of VCA Ig M and VCA Ig G without EBNA-1 Ig G indicates acute infection, whereas the presence of VCA Ig G and EBNA-1 Ig G without VCA Ig M is typical of past infection. However, serological findings may sometimes be difficult to interpret as VCA Ig G can be present without VCA Ig M or EBNA-1 Ig G in cases of acute or past infection, or all the three parameters may be detected simultaneously in the case of recent infection or during the course of reactivation. A profile of isolated EBNA-1 Ig G may also create some doubts. In order to interpret these patterns correctly, it is necessary to determine Ig G avidity, identify anti-EBV Ig G and Ig M antibodies by immunoblotting, and look for heterophile antibodies, anti-EA(D) antibodies or viral genome using molecular biology methods. These tests make it possible to define the status of the infection and solve any problems that may arise in routine laboratory practice.

Heat-shock protein 70 expression in shrimp Fenneropenaeus chinensis during thermal and immune-challenged stress

Using western immunoblotting, we obtained heat-shock protein 70 (HSP70) induction data and distribution in different tissues from shrimp Fenneropenaeus chinensis during thermal and immune-challenged stresses. This is probably the first report of the effects of various stressors on the expression of HSP70 in shrimp. HSP70 was prominently induced in hepatopancreas and gills, but not in muscle, eyestalk and hemolymph, when the shrimp were exposed to heat shock and Vibrio anguillavium-challenged stresses. Cold shock and WSSV treatment had no significant effects on the levels of HSP70 expression in all tissues examined. HSP70 induction was greatest after 2 h exposure to heat shock stress, which was elevated after acute heat shock exposure of 10℃ above ambient temperature.

Identification and Characterization of a New IgE-binding Protein in Mackerel (Scomber japonicus) by MALDI-TOF-MS

As fish is one source of the ‘big eight’ food allergens,the prevalence of fish allergy has increased over the past few years.In order to better understand fish allergy,it is necessary to identify fish allergens.Based on the sera from fish-allergenic patients,a 28 kDa protein from local mackerel (Scomber japonicus),which has not been reported as a fish allergen,was found to be reactive with most of the patients’ sera.The 28 kDa protein was analyzed by MALDI-TOF-MS (Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry).Mascot search in NCBI database (Date: 08/07/2010) showed that the top protein matched,i.e.triosephosphate isomerase (TPI) from Xiphophorus maculatus and Poecilia reticulata,had a mowse (molecular weight search) score of 98.In addition,TPI from Epinephelus coioides also matched this mackerel protein with a mowse score of 96.Because TPI is con-sidered as an allergen in other non-fish organisms,such as lychee,wheat,latex,archaeopotamobius (Archaeopotamobius sibiriensis) and crangon (Crangon crangon),we consider that it may also be an allergen in mackerel.

Rapid detection of intestinal pathogens in fecal samples by an improved reverse dot blot method

AIM:To develop a new, rapid and accurate reverse dot blot(RDB) method for the detection of intestinal pathogens in fecal samples.METHODS:The 12 intestinal pathogens tested were Salmonella spp., Brucella spp., Escherichia coli O157:H7, Clostridium botulinum , Bacillus cereus , Clostridium perfringens , Vibrio parahaemolyticus , Shigella spp., Yersinia enterocolitica, Vibrio cholerae, Listeria monocytogenes and Staphylococcus aureus.The two universal primers were designed to amplify two variable regions of bacterial 16S and 23S rDNA genes from all of the 12 bacterial species tested.Five hundred and forty fecal samples from the diarrhea patients were detected using the improved RDB assay.RESULTS:The methods could identify the 12 intestinal pathogens specifi cally, and the detection limit was as low as 103 CFUs.The consistent detection rate of the improved RDB assay compared with the traditional culture method was up to 88.75%.CONCLUSION:The hybridization results indicated that the improved RDB assay developed was a reliable method for the detection of intestinal pathogen in fecal samples.

Potassium bisperoxo(1,10-phenanthroline) oxovanadate suppresses proliferation of hippocampal neuronal cell lines by increasing DNA methyltransferases

Bisperoxo(1,10-phenanthroline) oxovanadate(BpV) can reportedly block the cell cycle. The present study examined whether BpV alters gene expression by affecting DNA methyltransferases(DNMTs), which would impact the cell cycle. Immortalized mouse hippocampal neuronal precursor cells(HT_(22)) were treated with 0.3 or 3 μM BpV. Proliferation, morphology, and viability of HT_(22) cells were detected with an IncuCyte real-time video imaging system or inverted microscope and 3-(4,5-dimethylthiazol-2-yl)-5(3-carboxymethonyphenol)-2-(4-sulfophenyl)-2H-tetrazolium, respectively. mRNA and protein expression of DNMTs and p21 in HT_(22) cells was detected by real-time polymerase chain reaction and immunoblotting, respectively. In addition, DNMT activity was measured with an enzyme-linked immunosorbent assay. Effects of BpV on the cell cycle were analyzed using flow cytometry. Results demonstrated that treatment with 0.3 μM BpV did not affect cell proliferation, morphology, or viability; however, treatment with 3 μM BpV decreased cell viability, increased expression of both DNMT3B mRNA and protein, and inhibited the proliferation of HT_(22) cells; and 3 μM BpV also blocked the cell cycle and increased expression of the regulatory factor p21 by increasing DNMT expression in mouse hippocampal neurons.

Evaluation of the role of H pylori infection in pathogenesis of gastric cancer by immunoblot assay

AIM： To elucidate the different serological reactions to H pylori using the immunoblotting technique for further understanding of its pathogenic role in gastric cancer. METHODS： A total of 54 patients were divided into two groups after upper gastrointestinal endoscopy： normal control group （25 patients） and gastric cancer group （29 patients）. Both groups were further divided into Hpylori （＋） and H pylori （-） subgroups based on the results of CLO test, Giemsa staining and culture. Sera were further analyzed with the immunoblotting technique （HelicoBIot 2.0, Genelabs Diagnostics, Singapore）. RESULTS： The positive rate of the immunoblotting test was as high as 88.9% in the H pylori （-） gastric cancer group and only 14.3% in the H pylori （-） normal control group with a statistically significant difference. CONCLUSION： The prevalence of H pylori infection is higher in gastric cancer patients than in the normal controls, suggesting that H pylori may play a role in the pathogenesis of gastric cancer.

Identification of the major allergen of Macrobrachium rosenbergii (giant freshwater prawn)

Objective:To characterize the major allergens of Macrobrachium rosenbergii.(giant freshwater prawn).Methods:Raw and cooked extracts of the giant freshwater prawn were prepared.The IgE reactivity pattern was identified by sodium dodecyl sulfate polyaerylamide gel electrophoresis(SDS-PAGE)and immunoblotting technique with the sera of 20 skin prick test(SPT)positive patients.The major allergen identified was then characterized using the proteomics approach involving a combination of two-dimensional(2-DE)electrophoresis,mass spectrometry and bioinformatics tools.Results:SDS-PAGE of the raw extract showed 23 protein bands(15-250 kDa)but those ranging from 40 to 100 kDa were not found in the cooked extract.From immunoblotting experiments,raw and cooked extracts demonstrated 11 and 5 IgE-binding proteins,respectively,with a molecular mass ranging from 15 to 155 kDa.A heat-resistant 36 kDa protein was identified as the major allergen of both extracts.In addition,a 42 kDa heat-sensitive protein was shown to be a major allergen of the raw extract.The 2-DE gel fractionated the prawn proteins to more than 50 different protein spots.Of these,10 spots showed specific:IgE reactivity with patients'sera.Matrix assisted laser desorption/ionization-lime of flight(MALDI-TOF)analysis led to identification of 2 important allergens,tropomyosin and arginine kinase.Conclusions:It can be concluded that the availability of such allergens would help in component-based diagnosis and therapy of prawn allergies.

Studies of the Kinetochore Proteins of the Regenerating Liver and the Liver Cells of Rats at Different Stages of Development

The kinetochore composition of rat liver cells was studied by indirect immunofluorescence andimmunoblotting using human anti-kinetochore/centromere autoantibodies(ACAs).Besides threemajor antigens(50kD,42 kD and 34 kD),ACAs used in this study could also identify those of 32-30 kD and 20 kD in newborn rat liver cells,90 kD in old rat liver cells,37 kD and 32-30 kD inregenerating liver cells.These results indicate that some kinetochore antigen(s)may be related to cellproliferation or specific for different stages of development.

Recognition with monoclonal antibodies of a Mr 71000 surface antigen of Plasmodium falciparum merozoites

Merozoite surface antigens can induce protective immune responses and may becandidate antigens for malaria vaccine.Four hybridoma cell lines secreting monoclonalantibodies against Plasmodium falciparum Fcc7801/HN were produced.Antibodies fromthree of the four lines showed significant growth-inhibiting effect on P.falciparum invitro.One monoclonal antibody,known as C6,conjugated the antigen located exclusivelyon the merozoite surface and distributed evenly over the entire surface,as wasdemonstrated by immunoelectron microscopy.C6 also precipitated a single protein of Mr71000.

Development of an ERK1/2 activation assay to determine relaxin-3/RXFP3 activation

OBJECTIVE To develop ERK1/2 activation assays to detect RXFP3 activation or inhibition by its agonists or antagonists.METHODS Plated HEK-RXFP3,CHO-RXFP3,HEK293 Tand CHO-K1 cells in poly-L-lysine coated well plates.The cells were serum starved and treated with either human relaxin-3(H3relaxin)(10nmol·L-1),R3B1-22R(10μmol·L-1)and pertussis toxin(PTX,100ng·mL-1).The cells were lysed and the ERK1/2 activation was determined by SDS-PAGE followed by immunoblotting for phosphorylated ERK1/2(pERK1/2)and total ERK1/2(tERK1/2)for the lysates.RESULTSThe quantification of the data revealed that the peak of ERK1/2activation can be detected precisely at 10 min post stimulation with 10nmol·L-1 H3 relaxin in both HEK-RXFP3 and CHO-RXFP3 cell lines in all three trials compared to the cells treated with vehicle(P<0.05).However,HEK-RXFP3 cells demonstrated a transient activation of ERK1/2and CHORXFP3 cells demonstrated a continuous activation of ERK1/2which was inhibited by the Gi inhibitor,PTX.Activation of ERK1/2was significantly inhibited by pre-treating the cells with RXFP3 antagonist R3B1-22 Rin HEK-RXFP3 cells.ERK1/2 activation was observed neither in wild type HEK293 Tnor in CHO-K1 cells.CONCLUSION The developed assay can detect RXFP3 activation or inhibition by agonists and antagonists via the detection of pERK1/2 in multiple cell lines.This assay will also be useful to detect signaling pathways upstream to ERK1/2 activation mediated by RXFP3.Activation of ERK1/2 in CHO-RXFP3 cells was mediated by Gi proteins at 10 min as well as at 25-35 min time points.

Rapid immunodiagnostic assays for Mycobacterium Tuberculosis infection

Purpose: There is a need for a continued effort to develop rapid immunodiagnostic assays for tuberculosis (TB) infection with greater sensitivity and specificity that can be used in the field and in the laboratory and that can be formatted for use with multiple species. This would help to obtain definitive early diagnosis of TB. The present study was developed to determine the role of using early secreted antigenic target-6 (ESAT-6) in immunodiagnosis of Mycobacterium tuberculosis. Methods: Serum samples were obtained from TB infected patients and normal healthy controls. Two rapid immunodiagnostic assays (Enzyme-linked immunosorbent assay (ELISA) and Immunoblotting) were performed. Results: The sensitivity of immunoblotting assay was 100%;however, ESAT-6 antigen was not able to discriminate between patients and normal controls. Application of direct ELISA using ESAT-6 antigen yielded 97.6% sensitivity and 75% specificity for the diagnosis of TB infection. Conclusion: In conclusion, the detection of antibodies against ESAT-6 antigen in the sera of TB patients by direct ELISA could be used as a preliminary assay for diagnosis of human M. tuberculosis infection. A combination of the ELISA with either radiological or microscopic examination is required to overcome the low specificity of the assay for negative results.

Expression of heat shock proteins (HSP27, HSP60, HSP70, HSP90, GRP78, GRP94) in hepatitis B virus-related hepatocellular carcinomas and dysplastic nodules

AIM: Expression of heat shock proteins (HSPs) is frequently up-regulated in hepatocellular carcinoma (HCC), which evolves from dysplastic nodule (DN) and early HCC to advanced HCC. However, little is known about the differential expression of HSPs in multistep hepatocarcinogenesis. It was the purpose of this study to monitor the expression of HSPs in multistep hepatocarcinogenesis and to evaluate their prognostic significance in hepatitis B virus (HBV)related HCC.METHODS: Thirty-eight HCC and 19 DN samples were obtained from 52 hepatitis B surface antigen-positive Korean patients. Immunohistochemical and dot immunoblot analyses of HSP27, HSP60, HSP70, HSP90, glucoseregulated protein (GRP)78, and GRP94 were performed and their expression at different stages of HCC development was statistically analyzed.RESULTS: Expression of HSP27, HSP70, HSP90, GRP78, and GRP94 increased along with the stepwise progression of hepatocarcinogenesis. Strong correlation was found only in GRP78 (Spearman's r= 0.802). There was a positive correlation between the expressions of GRP78, GRP94, HSP90, or HSP70 and prognostic factors of HCC. Specifically, the expression of GRP78, GRP94, or HSP90 was associated significantly with vascular invasion and intrahepatic metastasis.CONCLUSION: The expressions of HSPs are commonly up-regulated in HBV-related HCCs and GRP78 might play an important role in the stepwise progression of HBVrelated hepatocarcinogenesis. GRP78, GRP94, and HSP90 may be important prognostic markers of HBV-related HCC, strongly suggesting vascular invasion and intrahepatic metastasis.

Non-invasive diagnosis of H pylori infection: Evaluation of serological tests with and without current infection marker CIM

AIM:To evaluate the performance of commercially available immunochromatographic (ICT) and immunoblot tests covering the current infection marker CIM and conventional ELISA for the diagnosis of H pylori infection in adult dyspeptic patients. METHODS:Consecutive non-treated dyspeptic patients undergoing diagnostic endoscopy were tested for H pylori infection by culture, rapid urease test, and histology of gastric biopsy specimens. Serum from 61 H pylori infected and 21 non-infected patients were tested for anti-H pylori IgG antibodies by commercial ELISA (AccuBindTM ELISA, Monobind, USA), ICT (Assure H pylori Rapid Test, Genelabs Diagnostics, Singapore), and immunoblot (Helico Blot 2.1, Genelabs Diagnostics, Singapore) assays. ICT and immunoblot kits cover CIM among other parameters and their performance with and without CIM was evaluated separately. RESULTS:Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of ELISA were 96.7%, 42.8%, 83.1%, 81.8%, and 82.9%, of ICT were 90.1%, 80.9%, 93.2%, 73.9%, and 87.8%, of ICT with CIM were 88.5%, 90.4%, 96.4%, 73.0%, and 89.0%, of immunoblot were 98.3%, 80.9%, 93.7%, 94.4%, and 93.9%, and of immunoblot with CIM were 98.3%, 90.4%, 96.7%, 95.0%, and 96.3%, respectively. CONCLUSION:Immunoblot with CIM had the best performance. ICT with CIM was found to be more specific and accurate than the conventional ELISA and may be useful for non-invasive diagnosis of H pylori infection.

Preparation of Polyclonal Antibodies against NS3 Protein of Japanese Encephalitis Virus

Japanese encephalitis （JE） is a central nervous system disease caused by Japanese encephalitis virus （JEV）, which can infect human and a variety of animals and cause irreversible nerve damages. NS3 protein plays an important role in the process of JEV polyprotein hydrolysis, which is essential for JEV replication. Therefore, NS3 protein may be used as a potential drug target to treat Japanese encephalitis. In this study, the pET-28a-NS3 plasmid was successfully constructed and expressed in E. coli BL21 （ DE3 ） under IPTG induction. The molecular weight of the expressed recombinant protein was 55 ku, which was consistent with the expected result. The positive serum was prepared by immunizing BALB/c mice with NS3 protein and identified by indirect immunofluorescence （IFA）. The results showed that there was a fluorescence reaction between the prepared positive serum of NS3 protein and cells infected with JEV.

Profiles of Entamoeba histolytica—specific imunoglobulins in human sera

Objective:To determine the profdes of anti-Entamoeba histolytica(E.histolytica) IgA.IgC. and IgM in sera of diarrheic and non-diarrheic individuals and partially characterize target antigens.Methods:Serum samples from thirty diarrheic and thirty non-diarrheic individuals were subjected to IgA,IgG,and IgM profiling through enzyme-linked immunosorbent assay (EI.ISA),flow cytometry,and immunoblot.Results:ELBA titer results showed that both diarrheic and non-diarrheic individuals possess high levels of E.histolytica-specific IgG compared to IgA and IgM.How cytometry data showed that diarrheic serum samples had higher mean reaction percentages against E.histolytica cells compared to non-diarrheic samples.Immunoreactive E.histolytica proteins with molecular weights ranging belween 7 kDa and 292 kDa were recognized by diarrheic serum IgG,and 170 kDa and 250 kDa by non-diarrheic serum IgG. Conclusions:Our findings suggest that serum anti-E.histolytica IgG,compared with serum anti-E.histolytica IgA and IgM responses,was generally high in both diarrheic and nondiarrheic sera,indicating a past exposure to the organism both in symptomatic patients as well as in asymptomatic carriers,respectively.In addition,serum IgG from diarrheic and non-diarrheic patients were able to detect immunogenic E.histolytica proteins.