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Hans R, Thavaselvam D. Immunoassay-based evaluation of rOmp28 protein as a candidate for the identification of Brucella species. J Med Microbiol 2023; 72. [PMID: 37367949 DOI: 10.1099/jmm.0.001718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/28/2023] Open
Abstract
Introduction. Brucellosis is an important bacterial zoonosis, re-emerging as a serious public health concern in developing countries. Two major species, Brucella melitensis and Brucella abortus, cause recurrent facile infection in human. Therefore, rapid and accurate diagnosis for early disease control and prevention is needed in areas with low disease burden.Hypothesis. This study evaluated the sandwich enzyme-linked immunosorbent assay (ELISA) (S-ELISA) immunoassay for potential use of whole-cell (WC) and recombinant outer-membrane protein (rOmp28)-derived IgG polyclonals in sensitive detection of Brucella.Aim. Immunoassay-based WC detection of Brucella species in important sub-clinical matrices at lower limits of detection.Methodology. We purified recombinant rOmp28 with Ni-NTA gel affinity chromatography and produced IgG polyclonal antibodies (pAbs) using BALB/c mice and New Zealand white female rabbits against different antigens (Ags) of Brucella. Checkerboard sandwich ELISA and P/N ratio (optical density of 'P' positive test sample to 'N' negative control) were used for evaluation and optimization of the study. The pAbs were characterized using Western blot analysis and different matrices were spiked with WC Ag of Brucella.Results. Double-antibody S-ELISA was developed using WC Ag-derived rabbit IgG (capture antibody at 10 µg ml-1) and rOmp28-derived mice IgG (detection antibody at 100 µg ml-1) with a detection range of 102 to 108 cells ml-1 and a limit of detection at 102 cells ml-1. A P/N ratio of 1.1 was obtained with WC pAbs as compared to 0.6 and 0.9 ratios with rOmp28-derived pAbs for detecting B. melitensis 16M and B. abortus S99, respectively. An increased P/N ratio of 4.4 was obtained with WC Ag-derived rabbit IgG as compared to 4.2>4.1>2.4 ratios obtained with rabbit IgGs derived against cell envelope (CE), rOmp28 and sonicated antigen (SA) of Brucella with high affinity for rOmp28 Ag analysed on immunoblots. The rOmp28-derived mice IgG revealed two Brucella species at P/N ratios of 11.8 and 6.3, respectively. Upon validation, S-ELISA detected Brucella WCs in human whole blood and sera samples with no cross-reactivity to other related bacteria.Conclusion. The developed S-ELISA is specific and sensitive in early detection of Brucella from different matrices of clinical and non-clinical disease presentation.
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Affiliation(s)
- Richa Hans
- Division of Biodetector Development Test and Evaluation, Defence Research and Development Establishment, Defence Research and Development Organisation, Jhansi Road, Gwalior - 474002, India
| | - Duraipandian Thavaselvam
- Director (PM) O/o Director General Life Sciences (DGLS), Defence Research and Development Organization (DRDO) Headquarters, Ministry of Defence, SSPL Campus, Timarpur, New Delhi - 110011, India
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Zhang G, Dong H, Feng Y, Jiang H, Wu T, Sun J, Wang X, Liu M, Peng X, Zhang Y, Zhang X, Zhu L, Ding J, Shen X. The Pseudogene BMEA_B0173 Deficiency in Brucella melitensis Contributes to M-epitope Formation and Potentiates Virulence in a Mice Infection Model. Curr Microbiol 2022; 79:378. [DOI: 10.1007/s00284-022-03078-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Accepted: 10/07/2022] [Indexed: 11/06/2022]
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Shi F, Tang Y, Xu ZH, Sun YX, Ma MZ, Chen CF. Visual typing detection of brucellosis with a lateral flow immunoassay based on coloured latex microspheres. J Appl Microbiol 2021; 132:199-208. [PMID: 34319629 DOI: 10.1111/jam.15240] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Revised: 07/05/2021] [Accepted: 07/19/2021] [Indexed: 11/29/2022]
Abstract
AIMS Treatment and preventive control strategies for Brucella melitensis (B. melitensis) and Brucella abortus (B. abortus) infection differ. A lateral flow immunoassay (LFIA) for the rapid typing and detection of brucellosis by using polychromatic dye-doped latex microspheres (LMs) as a labelling material was developed. METHODS AND RESULTS This LFIA utilizes a double-antigen sandwich method in which the BP26 protein is used as the diagnostic antigen to detect brucellosis infection and the OMP31 protein is used as the identified antigen to distinguish between bovine and sheep brucellosis. Thus, people and animals infected with brucellosis can be diagnosed according to the different colours of the signals displayed on the detection lines. The results indicated that the accuracy of this assay was found to reach 98%, and the immunochromatographic test strip is highly accurate, shows good sensitivity and can facilitate typing diagnosis, among other features. CONCLUSIONS The established LFIA can distinguish B. melitensis infection from B. abortus infection and produces results in a short period of time while retaining the advantages of LFIAs. SIGNIFICANCE AND IMPACT OF THE STUDY This technology lays a foundation for the development of multi-disease test strips and the establishment of methods for rapid, multi-specimen quantitative detection and is thus of great importance for the development of medical diagnostic technologies.
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Affiliation(s)
- Feng Shi
- College of Life Science, Shihezi University, Shihezi, Xinjiang, P. R. China
| | - Yan Tang
- College of Animal Science and Technology, Shihezi University, Shihezi, Xinjiang, P. R. China
| | - Zhi-Hua Xu
- College of Life Science, Shihezi University, Shihezi, Xinjiang, P. R. China
| | - Yi-Xiao Sun
- College of Life Science, Shihezi University, Shihezi, Xinjiang, P. R. China
| | - Ming-Ze Ma
- College of Life Science, Shihezi University, Shihezi, Xinjiang, P. R. China
| | - Chuang-Fu Chen
- College of Animal Science and Technology, Shihezi University, Shihezi, Xinjiang, P. R. China
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Khurana SK, Sehrawat A, Tiwari R, Prasad M, Gulati B, Shabbir MZ, Chhabra R, Karthik K, Patel SK, Pathak M, Iqbal Yatoo M, Gupta VK, Dhama K, Sah R, Chaicumpa W. Bovine brucellosis - a comprehensive review. Vet Q 2021; 41:61-88. [PMID: 33353489 PMCID: PMC7833053 DOI: 10.1080/01652176.2020.1868616] [Citation(s) in RCA: 62] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Brucellosis is a zoonotic disease of great animal welfare and economic implications worldwide known since ancient times. The emergence of brucellosis in new areas as well as transmission of brucellosis from wild and domestic animals is of great significance in terms of new epidemiological dimensions. Brucellosis poses a major public health threat by the consumption of non-pasteurized milk and milk products produced by unhygienic dairy farms in endemic areas. Regular and meticulous surveillance is essentially required to determine the true picture of brucellosis especially in areas with continuous high prevalence. Additionally, international migration of humans, animals and trade of animal products has created a challenge for disease spread and diagnosis in non-endemic areas. Isolation and identification remain the gold standard test, which requires expertise. The advancement in diagnostic strategies coupled with screening of newly introduced animals is warranted to control the disease. Of note, the diagnostic value of miRNAs for appropriate detection of B. abortus infection has been shown. The most widely used vaccine strains to protect against Brucella infection and related abortions in cattle are strain 19 and RB51. Moreover, it is very important to note that no vaccine, which is highly protective, safe and effective is available either for bovines or human beings. Research results encourage the use of bacteriophage lysates in treatment of bovine brucellosis. One Health approach can aid in control of this disease, both in animals and man.
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Affiliation(s)
| | - Anju Sehrawat
- ICAR-Central Institute for Research on Buffaloes, Hisar, India
| | - Ruchi Tiwari
- Department of Veterinary Microbiology and Immunology, College of Veterinary Sciences, UP Pandit Deen Dayal Upadyaya Pashu Chikitsa Vigyan Vishwavidyalya Evam Go-Anusandhan Sansthan (DUVASU), Mathura, Uttar Pradesh, India
| | - Minakshi Prasad
- Department of Animal Biotechnology, College of Veterinary Sciences, Lala Lajpat Rai University of Veterinary and Animal Sciences (LUVAS), Hisar, India
| | - Baldev Gulati
- ICAR-National Research Centre on Equine, Hisar, India
| | - Muhammad Zubair Shabbir
- Quality Operations Laboratory, University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Rajesh Chhabra
- Department of Veterinary Microbiology, College of Veterinary Sciences, Lala Lajpat Rai University of Veterinary and Animal Sciences (LUVAS), Hisar, India
| | - Kumaragurubaran Karthik
- Central University Laboratory, Tamil Nadu Veterinary and Animal Sciences University, Chennai, Tamilnadu, India
| | - Shailesh Kumar Patel
- Division of Pathology, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly, India
| | - Mamta Pathak
- Division of Pathology, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly, India
| | - Mohd Iqbal Yatoo
- Division of Veterinary Clinical Complex, Faculty of Veterinary Sciences and Animal Husbandry, Sher-E-Kashmir University of Agricultural Sciences and Technology of Kashmir, Srinagar, Jammu and Kashmir, India
| | - Vivek Kumar Gupta
- Centre for Animal Disease Research and Diagnosis, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly, India
| | - Kuldeep Dhama
- Division of Pathology, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly, India
| | - Ranjit Sah
- Department of Microbiology, Tribhuvan University Teaching Hospital, Institute of Medicine, Kathmandu, Nepal
| | - Wanpen Chaicumpa
- Center of Research Excellence on Therapeutic Proteins and Antibody Engineering, Department of Parasitology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
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Islam S, Barua SR, Moni SP, Islam A, Rahman AKMA, Chowdhury S. Seroprevalence and risk factors for bovine brucellosis in the Chittagong Metropolitan Area of Bangladesh. Vet Med Sci 2020; 7:86-98. [PMID: 32949434 PMCID: PMC7840193 DOI: 10.1002/vms3.348] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 07/27/2020] [Accepted: 08/16/2020] [Indexed: 01/09/2023] Open
Abstract
Brucellosis is a neglected endemic zoonosis in Bangladesh and has a significant impact on public health and animal welfare of dairy farming as well as dairy farm economics. A cross‐sectional study was conducted to evaluate the seroprevalence of and risk factors for brucellosis in dairy cattle in the Chittagong metropolitan area (CMA) of Chittagong, Bangladesh. We collected serum samples (n = 158) from six randomly selected dairy farms in the CMA between February and November, 2015. The Rose Bengal Plate Test (RBPT) and a competitive ELISA (cELISA) were used as the screening and confirmatory tests respectively. Farm level and animal level demographic and risk factor data were collected using a questionnaire. The risk factors were analysed using a multivariable logistic regression with random effects. The overall seroprevalences of antibodies against brucellosis in cattle were 21.5% (34/158) and 7.6% (12/158) based on parallel and serial interpretation of the two tests respectively. Our results revealed that 20.3% (32/158) samples were positive using the RBPT and 8.9% (14/158) were positive using the cELISA. The within‐herd seroprevalence ranged from 10% to 26.3% and 5 to 20.7% using the RBPT and cELISA tests respectively. The odds of seropositivity were significantly higher in lactating cows (OR: 2.59; 95% CI: 1.02–6.55), cows producing less than 2 litres of milk (OR: 29.6; 95% CI: 4.3–353.8), cow producing 2–12 litres of milk (OR: 4.8; 95% CI: 1.1–33.4) and cows with reproductive disorders (OR: 3.2; 95% CI: 1.2–10.1). About 7.6% (12/158) and 1.3% (2/158) of cattle were found to be infected with acute and chronic brucellosis respectively. Based on these results, we suggest that cows that have reproductive disorders and are producing little milk should be prioritized for brucellosis screening in CMA. The screening tests should be used to control brucellosis in cattle in order to protect animal welfare, human health and to minimize the economic losses.
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Affiliation(s)
- Shariful Islam
- Chittagong Veterinary and Animal Sciences University (CVASU), Chittagong, Bangladesh.,Institute of Epidemiology, Disease Control and Research (IEDCR), Dhaka, Bangladesh.,Ecohealth Alliance, New York, NY, USA
| | - Shama Ranjan Barua
- Chittagong Veterinary and Animal Sciences University (CVASU), Chittagong, Bangladesh.,Department of Livestock Services, Farmgate, Dhaka, Bangladesh
| | - Shahnaj Parvin Moni
- Chittagong Veterinary and Animal Sciences University (CVASU), Chittagong, Bangladesh
| | - Ariful Islam
- Ecohealth Alliance, New York, NY, USA.,Centre for Integrative Ecology, School of Life and Environmental Science, Deakin University, Geelong, VIC, Australia
| | | | - Sharmin Chowdhury
- Chittagong Veterinary and Animal Sciences University (CVASU), Chittagong, Bangladesh
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Tian M, Song M, Yin Y, Lian Z, Li Z, Hu H, Guan X, Cai Y, Ding C, Wang S, Li T, Qi J, Yu S. Characterization of the main immunogenic proteins in Brucella infection for their application in diagnosis of brucellosis. Comp Immunol Microbiol Infect Dis 2020; 70:101462. [PMID: 32143107 DOI: 10.1016/j.cimid.2020.101462] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 02/21/2020] [Accepted: 02/25/2020] [Indexed: 02/07/2023]
Abstract
Brucellosis is an important zoonotic bacterial disease widespread in the world. The key step of control this disease is accurate diagnosis and elimination of diseased animals. The classic diagnostic methods, such as tube agglutination test, are inaccurate and nonspecific, because of cross-reaction with Yersinia enterocolitica serotype O:9. Previously, several proteins were reported as Brucella main immunogens. In this study, we used animal infection model to evaluate antibody production against OMP16, BP26, BLS, BCSP31, VirB12, SodC and GroEL proteins and investigated their application in diagnosis of brucellosis. The results showed that the BP26 and BLS are two best immunogenic proteins. In further study, we detected 44 clinical bovine sera using western blot, showing that the BP26 and BLS reacted with 30 Brucella-positive sera, but false-positive results were also shown in 14 Brucella-free sera. In an indirect ELISA assay, compared to lipopolysaccharide-based ELISA, the conformance of the BP26-based ELISA was 92.68 % in Brucella-positive sera, but only 52.94 % in Brucella-free sera. The BLS-based ELISA can hardly differentiate positive sera from negative sera. Besides, truncated fragments of the BP26 protein cannot exclude false-positive results in detection of Brucella-free sera. Altogether, although Brucella main immunogenic proteins have good reaction with Brucella-positive sera, false-positive reaction with Brucella-free sera may lead to misdiagnosis of brucellosis, suggesting that it should be more careful to use these immunogenic proteins as antigen targets to diagnosis of brucellosis.
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Affiliation(s)
- Mingxing Tian
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, 200241, China
| | - Meiying Song
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, 200241, China; College of Animal Science and Technology, Shandong Agricultural University, Taian, 271018, China
| | - Yi Yin
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, 200241, China
| | - Zhengmin Lian
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, 200241, China
| | - Zichen Li
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, 200241, China
| | - Hai Hu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, 200241, China
| | - Xiang Guan
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, 200241, China
| | - Yumei Cai
- College of Animal Science and Technology, Shandong Agricultural University, Taian, 271018, China
| | - Chan Ding
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, 200241, China
| | - Shaohui Wang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, 200241, China
| | - Tao Li
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, 200241, China
| | - Jingjing Qi
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, 200241, China
| | - Shengqing Yu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, 200241, China.
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7
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Lv R, Chen Y, Xia N, Liang Y, He Q, Li M, Qi Z, Lu Y, Zhao S. Development of a double-antibody sandwich ELISA for rapid detection to C-peptide in human urine. J Pharm Biomed Anal 2018; 162:179-184. [PMID: 30261444 DOI: 10.1016/j.jpba.2018.07.049] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Revised: 07/18/2018] [Accepted: 07/29/2018] [Indexed: 01/18/2023]
Abstract
C-peptide level is recognized as an important indicator of diabetes diagnosis. A sensitive and specific double-antibody sandwich enzyme-linked immunosorbent assay for the detection of C-peptide based on double antibody sandwich method was studied in this paper. The rabbit and hen were innunized with PLL-C-peptide and BSA-C-peptide respectively to obtain specific Yolk antibody (IgY) and polyclonal antibody used to construct the sandwich ELISA for the measurement of C-peptide. The limit of detection was 0.51 μg/mL and the half maximal inhibitory concentration (IC50) was 3.26 μg/mL. The method developed in the study showed no evident cross-reactivity with other similar analogs. The detection standard curve of C-peptide exhibited a good linearity (R2 = 0.9896, n = 15). 17 types of the urine of diabetes patients on c-peptide levels compared with the hospital type of diabetes information, with a conclusion of a high consistent rate. Therefore, the methods could be selectively used for rapid screening of C-peptide in human urine, and the type of diabetes has some referential significance.
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Affiliation(s)
- Rui Lv
- Department of Pharmaceutical Engineering, Faculty of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, People's Republic of China.
| | - Yingshan Chen
- Department of Pharmaceutical Engineering, Faculty of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, People's Republic of China.
| | - Nana Xia
- Department of Pharmaceutical Engineering, Faculty of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, People's Republic of China.
| | - Yuxin Liang
- Department of Pharmaceutical Engineering, Faculty of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, People's Republic of China.
| | - Qiyi He
- Department of Pharmaceutical Engineering, Faculty of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, People's Republic of China.
| | - Minyou Li
- Guangzhou Jinde Biotechnology Co., LTD, Guangzhou 510663, People's Republic of China.
| | - Zongxian Qi
- Guangzhou Jinde Biotechnology Co., LTD, Guangzhou 510663, People's Republic of China.
| | - Yeyu Lu
- Department of Pharmaceutical Engineering, Faculty of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, People's Republic of China.
| | - Suqing Zhao
- Department of Pharmaceutical Engineering, Faculty of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, People's Republic of China.
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Pathak P, Kumar A, Thavaselvam D. Evaluation of recombinant porin (rOmp2a) protein as a potential antigen candidate for serodiagnosis of Human Brucellosis. BMC Infect Dis 2017; 17:485. [PMID: 28693438 PMCID: PMC5504638 DOI: 10.1186/s12879-017-2588-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 07/03/2017] [Indexed: 01/10/2023] Open
Abstract
Background Brucellosis is an important zoonotic disease caused by different Brucella species and human brucellosis is commonly prevalent in different states of India. Among various Brucella species, B. melitensis is most pathogenic to human and included as category B biothreat which can cause infection through aerosol, cut, wounds in skin and contact with infected animals. The diagnosis of human brucellosis is very important for proper treatment and management of disease as there is no vaccine available for human use. The present study was designed to clone, express and purify immunodominant recombinant omp2a (rOmp2a) porin protein of B. melitensis and to evaluate this new antigen candidate for specific serodiagnosis of human brucellosis by highly sensitive iELISA (indirect enzyme linked immunosorbent assay). Method Omp2a gene of B. melitensis 16 M strain was cloned and expressed in pET-SUMO expression system. The recombinant protein was purified under denaturing conditions using 8 M urea. The purified recombinant protein was confirmed by western blotting by reacting with anti-HIS antibody. The sero-reactivity of the recombinant protein was also checked by reacting with antisera of experimentally infected mice with B. melitensis 16 M at different time points. Serodiagnostic potential of recombinant porin antigen was tested against 185 clinical serum samples collected from regions endemic to brucellosis in southern part of India by iELISA. The samples were grouped into five groups. Group 1 contained cultured confirmed positive serum samples of brucellosis (n = 15), group 2 contained sera samples from positive cases of brucellosis previously tested by conventional methods of RBPT (n = 28) and STAT (n = 26), group 3 contained sera samples negative by RBPT(n = 36) and STAT (n = 32), group 4 contained sera samples of other febrile illness and PUO case (n = 35) and group 5 contained confirmed negative sera samples from healthy donors (n = 23). Result The rOmp2a was found to be immunoreactive by iELISA and western blotting. The test showed a sensitivity of 93.75% and specificity of 95.83% when tested against 185 serum samples. For determination of statistical significance between experimental groups and control groups, Student’s t test was performed on the data. Conclusion Omp2a emerges as a potential antigen candidate for serodiagnosis of human brucellosis.
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Affiliation(s)
- Prachi Pathak
- Defence Research and Development Establishment, Jhansi Road, Gwalior, 474002, India
| | - Ashu Kumar
- Defence Research and Development Establishment, Jhansi Road, Gwalior, 474002, India
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