Antibody Detection on Mycoplasma capricolum subsp. Capripneumoniae in Qinghai Province

[Objective] The aim was to investigate the prevalence of Mycoplasma capricolum subsp. Capripneumoniae in Qinghai Province. [Method] By using indirect hemagglutination test kit for detecting Mycoplasma capricolum subsp. Capripneumoniae,208 goat serums were detected. [Result] The positive rate of goat sera was 16.3%,and the positive rate of sera from different regions ranged from 6.7% to 24.3%. [Conclusion] The infection rate of Mycoplasma capricolum subsp. Capripneumoniae was high in Qinghai Province,so it is necessary to strengthen the prevention and control of this disease.

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。

Clinical application of SARS-CoV-2 antibody detection and monoclonal antibody therapies against COVID-19

The purpose of this study was to investigate the clinical application of severe acute respiratory distress syndrome coronavirus-2(SARS-CoV-2)specific antibody detection and anti-SARS-CoV-2 specific monoclonal antibodies(mAbs)in the treatment of coronavirus infectious disease 2019(COVID-19).The dynamic changes of SARS-CoV-2 specific antibodies during COVID-19 were studied.Immunoglobulin M(IgM)appeared earlier and lasted for a short time,while immunoglobulin G(IgG)appeared later and lasted longer.IgM tests can be used for early diagnosis of COVID-19,and IgG tests can be used for late diagnosis of COVID-19 and identification of asymptomatic infected persons.The combination of antibody testing and nucleic acid testing,which complement each other,can improve the diagnosis rate of COVID-19.Monoclonal anti-SARS-CoV-2 specific antibodies can be used to treat hospitalized severe and critically ill patients and non-hospitalized mild to moderate COVID-19 patients.COVID-19 convalescent plasma,highly concentrated immunoglobulin,and anti-SARS-CoV-2 specific mAbs are examples of anti-SARS-CoV-2 antibody products.Due to the continuous emergence of mutated strains of the novel coronavirus,especially omicron,its immune escape ability and infectivity are enhanced,making the effects of authorized products reduced or invalid.Therefore,the optimal application of anti-SARS-CoV-2 antibody products(especially anti-SARS-CoV-2 specific mAbs)is more effective in the treatment of COVID-19 and more conducive to patient recovery.

Development and application of antibody microarray for white spot syndrome virus detection in shrimp

Detecting white spot syndrome virus （WSSV） in shrimp in high efficiency and veracity is important for disease prevention in aquaculture. Antibody-based mieroarray is a novel proteomic technology that can meet the requirements. In this study, we developed an antibody microarray for WSSV-detection in a specific and parallel way at multiple samples. First, seven slides each with different modifications were characterized by atomic force microscope, and were compared in the efficiency of immobilizing proteins. Of the seven, 3-dimensional structured agarose gel-modified slides were chosen appropriate for the microarray for having higher signal value and superior spot size. A purified rabbit anti-WSSV antibody was arrayed as the capture antibody of the microarray on the agarose gel-modified slides, and then the mieroarray slides were incubated in the tissue homogenate of sampled shrimp and the antibody-antigen complex was detected by Cy3-conjugated anti-WSSV monoclonal antibody. The results were measured by a laser chipscanner and analyzed with software. To obtain satisfied fluorescence signal intensity, optimal conditions were searched. The detection limit of the antibody microarray for WSSV is 0.62μg/mL, with a woven long shelf life for 6 months at 4℃ or 8 months at -20℃. Furthermore, concordance between antibody microarray and traditional indirect ELISA reached 100% for WSSV detection. These results suggest that the antibody microarray could be served as an effective tool for diagnostic and epidemiological studies of WSSV.

Antigen Detection in Canine Blastomycosis: Comparison of Different Antibody-Antigen Combinations in Two Competitive ELISAs

This present study was designed to evaluate four different Blastomyces dermatitidis antibody-antigen combinations (B5896 and T-58 antibodies and B5896 and WI-R antigens) for the detection of antigen in 36 urine specimens from dogs with blastomycosis using a standard indirect ELISA (STD) and a biotin-streptavidin ELISA (B-SA). The antigen detection sensitivity values ranged from 81% (B-SA: T-58 Ab + WI-R Ag) to 100% (STD and B-SA: B5896 Ab + WI-R Ag;B5896 Ab + B5896 Ag) with the antibody-antigen combinations in the two assays. Optimal detection was evidenced when the B5896 Ab was allowed to react with the urine specimens for 30 min at 37?C and then placed in the B-SA ELISA plates containing the B5896 Ag. The greatest absorbance value obtained with this antibody-antigen com-bination was 0.903 (range of 0.596 - 0.903) as compared to the control value of 1.246. The difference between the control absorbance and the test absorbance values was 0.343 which was considerably greater than the control-test values with the other combinations. This study thus showed that the results obtained in antigen detection assays are dependent upon the antibody used to react with the urine specimens as well as the antigen used in the enzyme immunoassay.

Sensitivity and Specificity Determinations with Isoelectric Focusing Fractions of <i>Blastomyces dermatitidis</i>for Antibody Detection in Serum Specimens from Infected Dogs

Blastomycosis and histoplasmosis manifest as lung and systemic fungal infections in mammals caused by Histoplasma capsulatum, and Blastomyces dermatitidis. These infections exhibit cross reactivity of antibodies which makes a correct diagnosis potentially elusive. The purpose of this study was to gain an understanding of which isoelectric focusing fractions (RotoforTM) of B. dermatitidis were reactive or cross reactive with serum specimens from dogs infected with B. dermatitidis, H. capsulatum, and Cryptococcus neoformans. Three serum specimens from dogs that were infected with B. dermatitidis, two dogs infected with H. capsulatum, and one dog infected with C. neoformans were assayed against the 20 B. dermatitidis RotoforTM fractions. Reactivity was determined using the indirect enzyme linked immunoassay (ELISA). Reactivity with B. dermatitidis was found predominantly in the protein fractions 1 - 6, and cross reactivity with H. capsulatum, and C. neoformans sera was found within the B. dermatitidis protein fractions 15 - 19.

ELISA Detection of Antibody against Canine Distemper Virus in Fox

Canine distemper is one of the most important common viral epidemics in farmed foxes. In this study, the whole blood samples of foxes that had been immunized with canine distemper vaccine were collected from a farming area in Changli County. The antibody against canine distemper virus in the 85 prepared serum samples were detected with a double-antibody sandwich ELtSA method. The results showed among the 85 samples from the 4 farms, 81 samples were antibody-positive, and only 4 samples had no antibody against canine distemper. The overall antibody level was higher in that farming area. It is indicated canine distemper vaccination and vaccination program have gotten attention from most of the local farmers, and the immune effect of canine distemper vaccine is better.

Detection of Atrazine Residue in Food Samples by a Monoclonal Antibody-based Enzyme-linked Immunosorbent Assay

Atrazine（AT,2-chloro-4-ethylamino-6-isopropyl-amino-s-triazine）has been detected in ground water in several areas of the United States for many years,as well as in China,wherein the growth rate of its gross

Comparison of Multiplex Fluorescent PCR with Serum Type-specific Antibody Detection in Diagnosis of Genital Herpes

Objectives: To compare multiplex fluorescent PCRwith serum type-specific antibody detection in thediagnosis of herpes simplex virus (HSV) infection andto evaluate its significance in the diagnosis of genitalherpes.Methods: We detected HSV infection in 121 speci-mens collected from patients with genital herpesusing both multiplex fluorescent PCR and serum type-specific antibody detection. HSV viral isolation wasused as the standard control.Results: When compared with the viral isolation, thesensitivity and specificity for multiplex fluorescentPCR were 100% and 88.89%, respectively afterdiscrepant analysis. The sensitivity and specificity fortype-specific antibody detection was 77.68 % and77.78 %, respectively. However, the type-specificantibody detected HSV in two asymptomatic patientswhile the multiplex fluorescent PCR couldn’t detectany HSV DNA from those specimens.Conclusions: Multiplex fluorescent PCR is a verysensitive and specific method for detection and typingof HSV in the lesion of genital herpes, it failed todetect HSV DNA from the asymptomatic patients.Serum type-specific antibody detection was a lesssensitive and specific test but could detect the specificantibody from some asymptomatic patients. Thecombination of these two techniques would allow rapid,sensitive and accurate detection and typing of HSVand help clinical diagnosis and epidemiologic survey-ing of genital herpes.

Comparison of antibody detection with <i>Blastomycesdermatitidis</i>yeast lysate antigens in serum specimens from immunized rabbits and infected dogs

This present study was designed to evaluate B. dermatitidis antigens, prepared from two isolates (B5896, 597), when the yeast cells were allowed to lyse in distilled water for one day or seven days. The indirect enzyme-linked immunosorbent assay (ELISA) was used to determine the ability of the lysate reagents to detect antibodies in 30 rabbit and 30 dog serum specimens. Mean absorbance values with B5896 lysate antigen ranged from 1.637 (day 1) to 1.461 (day 7) and absorbance values with 597 antigen ranged from 1.579(day 1) to 1.396 (day 7) with the serum specimens from immunized rabbits. Serum specimens from infected dogs yielded absorbance values ranging from 1.672 (day 1) to 1.763 (day 7) with the B5896 and values ranging from 1.909 (day 1) to 1.224 (day 7) with the 597. Optimal reactivity was obtained with the day 1 lysate using both lysate antigens against the rabbit sera and with the 597 antigen against the dog sera. Slightly greater reactivity was evidenced with the day 7 B5896 antigen when the dog sera was tested. Comparative studies are continuing in order to produce an optimal anti-genic preparation for antibody detection in blastomycosis.

Comparison of Antibody Detection with Yeast Lysate Antigens Prepared from Blastomyces dermatitidis Dog Isolates from Wisconsin and Tennessee

Blastomyces dermatitidis, the causative agent of blastomycosis, a potentially lethal dimorphic fungal disease of humans and animals has been difficult to diagnose in the clinical laboratory. We are attempting to develop and improve immunodiagnostic assays by producing novel yeast lysate reagents for the detection of antibodies in blastomycosis. The objective of this study was to use lysate antigens prepared from four B. dermatitidis antigens isolated from dogs infected with blastomycosis from two different endemic areas (Wisconsin and Tennessee) testing for the detection of antibodies in serum specimens from immunized rabbits and infected dogs using the indirect ELISA. In the dog sera, absorbance values ranged from 0.774 to 1.350, while the rabbit sera values ranged from 0.533 to 1.191. Antigen T-58 appeared to lack any geographical specificity in antibody detection, which could prove useful in future immunodiagnostic detection of blastomycosis infections.

Development of a Multi-Plex Electrochemiluminescent Assay for the Detection of Serum Antibody Responses to Meningococcal Conjugate Vaccines

Neisseria meningitidis is a gram negative diplococcal bacterium. Worldwide, N. meningitidis is the leading cause of bacterial meningitis and sepsis, with five serogroups (A, B, C, Y, and W-135) responsible for the majority of the disease. Multivalent (A, C, Y, and W-135) polysaccharide and conjugate vaccines have been licensed in the United States and elsewhere and are widely available. We have developed a multi-plexed electrochemiluminescent assay to quantitate serum antibody responses to meningococcal polysaccharides A, C, Y, and W-135 to allow for rapid evaluation of li- censed and investigational vaccines. A 96-well plate containing a carbon electrode arrayed with polysaccharides A, C, Y, and W-135 on separate spots within each well has been developed for simultaneous detection of polysaccharidespecific antibodies in serum samples from vaccinated individuals. The assay conditions were optimized using the anti-meningococcal serogroup A/C reference serum pool, CDC 1992 (NIBSC 99/706), through evaluation of plate types, coating polysaccharide concentrations, and blocking and serum diluent buffers. Comparison of single and multiplex assays demonstrated the sensitivity, specificity, and speed of the multi-plex format for the quantification of serum antibody responses to N. meningitidis polysaccharides A, C, Y and W-135.

GENE ENGINEERING EB VIRUS MEMBRANE ANTIGEN IN DETECTION OF MA-IgA ANTIBODY(COMPARISON WITH VCA-IgA AND EA-IgA ANTIBODIES)

With gene engineering EB virus membrane antigen as the diagnostic antigen, indirect immunofluo-rescence (IF) assay was used to detect IgA antibody against EB virus membrane antigen (MA-IgA) in sera from 202 nasopharyngeal carcinoma (NPC) patients and 315 controls (normal and patients with other tumors). MA-IgA antibody was positive in 96.8% of the pretreatment NPC patients with a GMT of 1:36.3. MA-IgA detection by this method was more sensitive than EA-IgA detection by IE. In contrast, patients with tumors other than NPC were negative for MA-IgA antibody. 9.1% of VCA-IgA positive persons were MA-IgA positive with a GMT of less than 1:5. No MA-IgA positive was found in VCA-IgA negatives. The results indicated that this method was relatively specific. In the treatment group, the positive rate and GMT of MA-IgA antibody declined with increase in survival time and the decline was faster than VCA-IgA. When recurrence or distant metastasis developed, similar to VCA-IgA and EA-IgA antibodies, the positive rate and GMT of MA-IgA antibody increased to its pretreatment level. Therefore, MA-IgA detection might be valuable in the early diagnosis and monitor of NPC.

Comparison of Two Enzyme Immunoassays and Four Lysate Antigens for the Detection of Antibody in Canine Blastomycosis

Blastomycosis, the systemic fungal disease of humans and animals caused by Blastomyces dermatitidis and the cryptic species Blastomyces gilchristii, is often misdiagnosed as a bacterial or viral pulmonary disease. Therefore, the development of improved immunodiagnostic assays for this disease has been the primary focus of research in our laboratory. The present study was designed to evaluate four Blastomyces yeast-phase lysate antigenic preparations (human, 597, Eagle River, WI;dog, ERC-2, WI;Human, B5927, Mountain Iron, MN;soil, 85, Georgia, ATCC 56920) for their ability to detect antibody in 48 serum specimens from dogs with diagnosed blastomycosis using an indirect ELISA (STD) compared to a biotin-streptavidin ELISA (B-SA). All four lysate antigens were able to detect antibodies in the specimens with mean absorbance values ranging from 0.930 (B5927) to 1.142 (ERC-2) with the STD ELSA and from 1.395 (B5927) to 1.775 (85) with the B-SA ELISA. The results indicated that both ELISA methods could be utilized for antibody detection, but the B-SA ELISA exhibited greater sensitivity than the STD ELISA with all four of the lysates.

Diagnostic performance and problem analysis of commercial tuberculosis antibody detection kits in China

Background: The diagnosis of bacterium-negative pulmonary tuberculosis(TB) and extra-pulmonary TB is challenging clinically. The detection of the anti-TB antibody has an important, auxiliary, clinical diagnostic value. Therefore, TB antibody detection kits should be screened and evaluated, and the reagents with the highest sensitivity and specificity should be chosen and used clinically.Methods: The diagnostic performance of 7 commercially available TB antibody detection kits(kits A, B, C, D, E, F and G) based on the gold immunoassay detection of immunoglobulin(Ig) G or IgM antibodies were simultaneously evaluated and compared in 62 TB cases and 56 non-TB cases in a laboratory. A retrospective analysis including 2549 cases was carried out to assess the clinical diagnosis values of bacteriological examinations and TB antibody tests(kits B and H used in the clinic).Results: The sensitivities of TB antibody kits A, B, C, D, E, F and G in the sera from 62 TB patients were 50.0%, 83.9%, 38.7%, 9.7%, 48.4%, 69.4% and 79.0%, respectively; the sensitivities in the sera from 24 smear-negative TB patients were 29.2%, 79.2%, 29.2%, 12.5%, 29.2%, 54.2% and 79.2%, respectively; the specificities in the sera from 56 nonTB patients were 73.2%, 25.0%, 85.7%, 96.4%, 78.6%, 78.6% and 50.0%, respectively. Of the 2549 clinically diagnosed cases, there were 1752 pulmonary TB cases, 505 extra-pulmonary TB cases, 87 old pulmonary TB cases and 205 non-TB cases. The positive results for smear, culture, TB antibody kit B and kit H in pulmonary TB cases were 39.8%(543/1365), 48.6%(372/765), 45.8%(802/1752) and 25.2%(442/1752), respectively; the results in extra-pulmonary TB cases were 3.4%(6/178), 5.8%(4/69), 35.4%(179/505), and 11.3%(57/505), respectively; the results in old pulmonary TB cases were 0%(0/64), 0%(0/30), 32.2%(28/87), and 9.2%(8/87), respectively; and the results in non-TB cases were 0%(0/121), 0%(0/56), 21.5%(44/205), and 2.4%(5/205), respectively. Of 624 smear-positive and/or culture-positive pulmonary TB cases, the sensitivities of antibody test kits B and H were 53.0% and 36.4%, respectively. Of 901 smear-negative and/or culture-negative pulmonary TB cases, the sensitivities of antibody test kits B and H were 42.5% and 19.0%, respectively. The positive rate of antibody detection in the bacterium-positive pulmonary TB cases was significantly higher than that in the bacterium-negative pulmonary TB cases(P<0.05).Conclusion: The colloidal gold-labeled TB antibody IgG detection assay is a simple, rapid and economical method that provides a better clinical auxiliary diagnosis value on TB, especially in smear-negative pulmonary TB and extrapulmonary TB. The production, quality control, screening and evaluation of antibody detection kits are very important for its clinical application.

Development of Double Antibody Sandwich ELISA for Detection of Duck or Goose Flavivirus

In order to establish double antibody sandwich enzyme-linked immunosorbent assay （DAS-ELISA） for detection of duck or goose flavivirus, polyclonal antibody against the flavivirus strain JS804 in geese and monoclonal antibody against the E protein of flavivirus strain JS804 in geese were used as the capture antibody and detection antibody, respectively. The optimal dilution of the capture antibody and detecting antibody capable of detecting the flavivirus strain JS804 in geese were 1：3 200 and 1：160 in the check-board titration, respectively. The reaction time of sample was 1 h, and the optimal working dilution of HRP-labeled goat-anti-mouse IgG was 1：10 000. The positive standard value was 0.247 （OD450.m）. The geese flavivirus could be detected at a minimal concentration of 1.875 μg mL^-1. The ELISA had no cross-reaction with Newcastle disease virus （NDV）, Avian influenza virus （AIV）, Infectious bronchitis virus （IBV）, Infectious bursal disease virus （IBDV）, Duck hepatitis virus （DHV）, and Gosling plague virus （GPV）. Twenty clinical samples were detected by the DAS-ELISA and RT-PCR respectively, with the agreement rate of 75%. The results revealed that the DAS-ELISA possessed favorable specificity and higher sensitivity, indicating a suitable method for rapid detection of the duck or goose flavivirus.

Monoclonal antibody-based serological detection of Citrus yellow vein clearing virus in citrus groves

Citrus yellow vein clearing virus （CYVCV） is considered as the causal agent of Citrus yellow vein clearing disease and belongs to the genus Mandarivirus in the family Alphaflexiviridae. Capsid protein （CP） of CYVCV Chongqing isolate （CYVCV- CQ） was produced using a prokaryotic expression system and used as the immunogen for monoclonal antibody （MAb） production. Four highly specific and sensitive murine MAbs and one polyclonal antibody were prepared in this study. Titers of the four MAbs in ascites fluids ranged from 10-6 to 10-7 as determined by indirect enzyme-linked immunosorbent assay （ELISA）. Three serological assays, including dot enzyme-linked immunosorbent assay （dot-ELISA）, tissue blot-ELISA, and double-antibody sandwich （DAS）-ELISA, were developed for quick and reliable detections of CYVCV in citrus samples. The developed dot-ELISA and DAS-ELISA methods could detect CYVCV in the infected citrus leaf crude extracts diluted at 1：2 560 and 1：10 240 （w/v, g mL^-1）, respectively. The detection result of 125 citrus leaf samples collected from citrus groves in Yunnan Province and Chongqing Municipality of China showed that approximately 36% samples were positive for CYVCV. This virus was, however, not＇detected in any sample collected from Zhejiang or Jiangxi Province, China.