1
|
Taylor C, Belin E, Brodbelt D, Klaasen HLBM, Catchpole B. Exploration of the potential utility of the luciferase immunoprecipitation system (LIPS) assay for the detection of anti-leptospira antibodies in dogs. Vet Immunol Immunopathol 2023; 264:110661. [PMID: 37827091 DOI: 10.1016/j.vetimm.2023.110661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 10/04/2023] [Indexed: 10/14/2023]
Abstract
Canine leptospirosis represents a diagnostic challenge to veterinarians, due to the variability in presenting clinical signs and interpretation of serology test results in dogs that have been vaccinated previously. None of the commercially available serological assays, including the microscopic agglutination test (MAT), have been verified to be capable of differentiating infected from vaccinated animals (DIVA). Recent work identified that half of primary practice attending dogs were up to date with their leptospirosis vaccination and would be expected to have circulating anti-leptospira antibodies (Taylor et al., 2022), indicating that this is a relevant issue for suspected leptospirosis cases in dogs in the UK. This study aimed to explore the utility of three leptospiral outer membrane proteins (OMPs: LipL32, LipL21 and LipL41) as potential DIVA targets in the luciferase immunoprecipitation system (LIPS) assay. N and C terminal nanoluciferase tagged recombinant proteins were generated for each OMP. Differences in reactivity between serum samples from MAT positive dogs (n = 29) and paired samples (n = 6 dogs) taken pre and 21 days post leptospirosis vaccination were assessed against these six constructs. Reactivity was greater towards the N terminal than the C terminal recombinant proteins for all three OMPs. None of the constructs appeared to demonstrate DIVA capability, although two (pNLF1-N-FLAG/LipL32 and pNLF1-N-FLAG/LipL21) were able to detect vaccine seroconversion. The findings of this work suggest that these particular OMP targets do not offer DIVA ability, however LipL32 and LipL21 may be suitable for use in immunoassays for vaccine trials or for detection of infections in humans, where there is no requirement for DIVA capability.
Collapse
Affiliation(s)
- C Taylor
- Royal Veterinary College, Hawkshead Lane, Hatfield, Hertfordshire, United Kingdom.
| | - E Belin
- Royal Veterinary College, Hawkshead Lane, Hatfield, Hertfordshire, United Kingdom
| | - D Brodbelt
- Royal Veterinary College, Hawkshead Lane, Hatfield, Hertfordshire, United Kingdom
| | - H L B M Klaasen
- Global Companion Animals Research and Development, Merck Sharp and Dohme Animal Health, Boxmeer, the Netherlands
| | - B Catchpole
- Royal Veterinary College, Hawkshead Lane, Hatfield, Hertfordshire, United Kingdom
| |
Collapse
|
2
|
Shien Yeoh T, Yusof Hazrina H, Bukari BA, Tang TH, Citartan M. Generation of an RNA aptamer against LipL32 of Leptospira isolated by Tripartite-hybrid SELEX coupled with in-house Python-aided unbiased data sorting. Bioorg Med Chem 2023; 81:117186. [PMID: 36812779 DOI: 10.1016/j.bmc.2023.117186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 01/16/2023] [Accepted: 01/23/2023] [Indexed: 02/05/2023]
Abstract
Leptospirosis is a potentially life-threatening zoonosis caused by pathogenic Leptospira. The major hurdle of the diagnosis of Leptospirosis lies in the issues associated with current methods of detection, which are time-consuming, tedious and the need for sophisticated, special equipments. Restrategizing the diagnostics of Leptospirosis may involve considerations of the direct detection of the outer membrane protein, which can be faster, cost-saving and require fewer equipments. One such promising marker is LipL32, which is an antigen with high amino acid sequence conservation among all the pathogenic strains. In this study, we endeavored to isolate an aptamer against LipL32 protein via a modified SELEX strategy known as tripartite-hybrid SELEX, based on 3 different partitioning strategies. In this study, we also demonstrated the deconvolution of the candidate aptamers by using in-house Python-aided unbiased data sorting in examining multiple parameters to isolate potent aptamers. We have successfully generated an RNA aptamer against LipL32 of Leptospira, LepRapt-11, which is applicable in a simple direct ELASA for the detection of LipL32. LepRapt-11 can be a promising molecular recognition element for the diagnosis of leptospirosis by targeting LipL32.
Collapse
Affiliation(s)
- Tzi Shien Yeoh
- Department of Biomedical Science, Advanced Medical & Dental Institute (AMDI), Universiti Sains Malaysia, Bertam, 13200 Kepala Batas, Penang, Malaysia
| | - Hamdani Yusof Hazrina
- Department of Biomedical Science, Advanced Medical & Dental Institute (AMDI), Universiti Sains Malaysia, Bertam, 13200 Kepala Batas, Penang, Malaysia
| | - Bakhtiar A Bukari
- School of Medicine, Deakin University, 3216 Geelong, Victoria, Australia
| | - Thean-Hock Tang
- Department of Biomedical Science, Advanced Medical & Dental Institute (AMDI), Universiti Sains Malaysia, Bertam, 13200 Kepala Batas, Penang, Malaysia
| | - Marimuthu Citartan
- Department of Biomedical Science, Advanced Medical & Dental Institute (AMDI), Universiti Sains Malaysia, Bertam, 13200 Kepala Batas, Penang, Malaysia.
| |
Collapse
|
3
|
Yeoh TS, Tang TH, Citartan M. Isolation of a novel DNA aptamer against LipL32 as a potential diagnostic agent for the detection of pathogenic Leptospira. Biotechnol J 2023; 18:e2200418. [PMID: 36426669 DOI: 10.1002/biot.202200418] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 11/01/2022] [Accepted: 11/02/2022] [Indexed: 11/27/2022]
Abstract
Leptospirosis is a potentially life-threatening zoonosis caused by pathogenic Leptospira and for rapid diagnostics, direct detection is desirable. LipL32 protein is the most suitable biomarker for direct detection. DNA aptamers are sought to be generated against LipL32 by Systemic Evolution of Ligands via Exponential Enrichment (SELEX). LepDapt-5a is the most potent aptamer candidate among all the candidates, as determined by direct Enzyme-linked Aptasorbent Assay (ELASA). LepDapt-5a was predicted to form a G-quadruplex structure as predicted by QGRS Mapper and validated experimentally by direct ELASA. The diagnostic potential of the aptamer was further tested on a direct and sandwich ELASA platform. A LOD of 106 mL-1 and 105 mL-1 were estimated by direct and sandwich ELASA platforms, respectively, which are within the range associated with leptospiremia levels. The dot blot assay developed was able to attain a LOD of 104 CFU mL-1 against pathogenic Leptospira, which is also within the leptospiremia level. This is the first-ever DNA aptamer and hybrid-heterodimeric aptamer constructed against LipL32. The diagnostic potentiality of the LepDapt-5a DNA aptamer was proven on three major diagnostic platforms, which are direct ELASA, sandwich ELASA, and aptamer-based dot assay.
Collapse
Affiliation(s)
- Tzi Shien Yeoh
- Advanced Medical & Dental Institute (AMDI), Universiti Sains Malaysia, Bertam, 13200 Kepala Batas, Penang, Malaysia
| | - Thean-Hock Tang
- Advanced Medical & Dental Institute (AMDI), Universiti Sains Malaysia, Bertam, 13200 Kepala Batas, Penang, Malaysia
| | - Marimuthu Citartan
- Advanced Medical & Dental Institute (AMDI), Universiti Sains Malaysia, Bertam, 13200 Kepala Batas, Penang, Malaysia
| |
Collapse
|
4
|
Fernandes LGV, Avelar KES, Romero EC, Heinemann MB, Kirchgatter K, Nascimento ALTO. A New Recombinant Multiepitope Chimeric Protein of Leptospira interrogans Is a Promising Marker for the Serodiagnosis of Leptospirosis. Trop Med Infect Dis 2022; 7:362. [PMID: 36355904 PMCID: PMC9694704 DOI: 10.3390/tropicalmed7110362] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 10/20/2022] [Accepted: 11/02/2022] [Indexed: 09/10/2024] Open
Abstract
The zoonotic disease leptospirosis is caused by pathogenic species of the genus Leptospira and was recently included in the list of Neglected Diseases by the World Health Organization. Leptospirosis burden is estimated to have over a million human cases and cause 60 thousand deaths annually, in addition to its economic impact and veterinary concern. The microscopic agglutination test (MAT), recommended by the World Health Organization, exhibits reduced sensitivity at the beginning of the disease, in addition to being technically difficult. New recombinant antigens are being pursued for rapid and specific serodiagnostic tests, especially in the initial phase of the disease, and chimeric multiepitope proteins are a strategy with a great potential to be implemented in serology. Based on previous subproteomic results, we designed a synthetic construct comprising 10 conserved leptospiral surface antigens, and the recombinant protein was purified and evaluated regarding its diagnostic potential. The protein termed rChi2 was recognized by antibodies in serum from patients both at the onset (MAT-) and in the convalescent (MAT+) phase in 75 and 82% of responders, respectively. In addition, rChi2 immunization in hamsters elicited a strong humoral response, and anti-rChi2 antibodies recognized several immobilized intact Leptospira species, validating its potential as an early, broad, and cross-reactive diagnostic test.
Collapse
Affiliation(s)
- Luis G. V. Fernandes
- Laboratório de Desenvolvimento de Vacinas, Instituto Butantan, Avenida Vital Brazil, 1500, Sao Paulo 05503-900, SP, Brazil
| | - Kátia E. S. Avelar
- Laboratório de Referência Nacional para Leptospirose, Instituto Oswaldo Cruz—Fiocruz, Avenida Brasil, 4365, Manguinhos, Rio de Janeiro 21040-900, RJ, Brazil
| | - Eliete C. Romero
- Centro de Bacteriología, Instituto Adolfo Lutz, Sao Paulo 01246-902, SP, Brazil
| | - Marcos B. Heinemann
- Laboratório de Zoonoses Bacterianas do VPS, Faculdade de Medicina Veterinária e Zootecnia, USP, Sao Paulo 05508-270, SP, Brazil
| | - Karin Kirchgatter
- Laboratório de Bioquímica e Biologia Molecular, Instituto Pasteur, Sao Paulo 01027-000, SP, Brazil
- Programa de Pós Graduação em Medicina Tropical, Faculdade de Medicina, Universidade de São Paulo, Sao Paulo 05403-000, SP, Brazil
| | - Ana L. T. O. Nascimento
- Laboratório de Desenvolvimento de Vacinas, Instituto Butantan, Avenida Vital Brazil, 1500, Sao Paulo 05503-900, SP, Brazil
| |
Collapse
|
5
|
MB T, AF T, ALTO N. The leptospiral LipL21 and LipL41 proteins exhibit a broad spectrum of interactions with host cell components. Virulence 2021; 12:2798-2813. [PMID: 34719356 PMCID: PMC8632080 DOI: 10.1080/21505594.2021.1993427] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 09/08/2021] [Accepted: 10/08/2021] [Indexed: 01/09/2023] Open
Abstract
Leptospirosis is a globally prevalent zoonotic disease, and is caused by pathogenic spirochetes from the genus Leptospira. LipL21 and LipL41 are lipoproteins expressed strongly on the outer membrane of pathogenic Leptospira spp. Many studies have shown that both proteins are interesting targets for vaccines and diagnosis. However, their role in host-pathogen interactions remains underexplored. Therefore, we evaluated the capacity of LipL21 and LipL41 to bind with glycosaminoglycans (GAGs), the cell receptors and extracellular matrix, and plasma components by ELISA. Both proteins interacted with collagen IV, laminin, E-cadherin, and elastin dose-dependently. A broad-spectrum binding to plasma components was also observed. Only LipL21 interacted with all the GAG components tested, whereas LipL41 presented a concentration-dependent binding only for chondroitin 4 sulfate. Although, both proteins have the ability to interact with fibrinogen, only LipL21 inhibited fibrin clot formation partially. Both proteins exhibited a decrease in plasminogen binding in the presence of amino caproic acid (ACA), a competitive inhibitor of lysine residues, suggesting that their binding occurs via the kringle domains of plasminogen. LipL41, but not LipL21, was able to convert plasminogen to plasmin, and recruit plasminogen from normal human serum, suggesting that the interaction of this protein with plasminogen may occur in physiological conditions. This work provides the first report demonstrating the capacity of LipL21 and LipL41 to interact with a broad range of host components, highlighting their importance in host-Leptospira interactions.
Collapse
Affiliation(s)
- Takahashi MB
- Laboratório de Desenvolvimento de Vacinas, Instituto Butantan, São Paulo, Brazil
- Programa de Pós-Graduação Interunidades Em Biotecnologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | - Teixeira AF
- Laboratório de Desenvolvimento de Vacinas, Instituto Butantan, São Paulo, Brazil
| | - Nascimento ALTO
- Laboratório de Desenvolvimento de Vacinas, Instituto Butantan, São Paulo, Brazil
| |
Collapse
|
6
|
Samakchan N, Thinwang P, Boonyom R. Oral immunization of rat with chromosomal expression LipL32 in attenuated Salmonella vaccine induces immune respond against pathogenic Leptospira. Clin Exp Vaccine Res 2021; 10:217-228. [PMID: 34703804 PMCID: PMC8511595 DOI: 10.7774/cevr.2021.10.3.217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 09/05/2021] [Indexed: 11/23/2022] Open
Abstract
Purpose Leptospirosis caused by Leptospira spp. remains a global health problem. Available commercial leptospiral vaccines have shown an ineffective prevention for leptospiral infection. The aim of this study was to develop leptospirosis vaccine using recombinant attenuated Salmonella vaccine (RASV) as a platform. We expected that this vaccine has ability to continuous and strongly stimulate immune systems including protective mucosal, humoral, and cell mediated immunity in rat model. Materials and Methods In this study, we engineered RASV, NRSL32 strain containing chromosomal fusion between nucleotides encoding secretion signal of SPI-2 effector protein, SspH2 and gene encoding major pathogenic leptospiral outer membrane lipoprotein, LipL32. Subsequently, our modified RASV was oral vaccination to rat and blood samples were taken for assessment of immune responses. Results Our Salmonella NRSL32 strain showed expression and secretion of SspH21-215-LipL32 recombinant protein via SPI-2 T3SS. After oral administration of NRSL32 strain to rats, significant titers of total immunoglobulin G (IgG) and immunoglobulin A against rLipL32 were observed in long period up to 77 days after vaccination. The stimulated antibody showed ability to specific bind with LipL32 protein on surface of pathogenic Leptospira spp. Additionally, the balance level of IgG2a/IgG1 ratio and level of interferon-γ and interleukin-4 secretion were detected. Conclusion The results showed that our RASV platform with chromosomal expression elicited effective immune responses to leptospiral antigen. Moreover, this platform was capable for simultaneous stimulation of Th1 and Th2-biased responses. Further investigation is necessary study of protective efficacy against leptospiral infection in animal models.
Collapse
Affiliation(s)
- Natthapon Samakchan
- Department of Medical Technology, Faculty of Allied Health Sciences, Naresuan University, Phitsanulok, Thailand
| | - Patipat Thinwang
- Department of Medical Technology, Faculty of Allied Health Sciences, Naresuan University, Phitsanulok, Thailand
| | - Rerngwit Boonyom
- Department of Medical Technology, Faculty of Allied Health Sciences, Naresuan University, Phitsanulok, Thailand
| |
Collapse
|
7
|
Gomes CK, Pacce VD, de Oliveira NR, Jorge S, Collares TF, Pinto Seixas Neto AC, Amaral MG, Dellagostin OA, Hartwig DD. Monoclonal antibodies against LipL32 confer prophylactic protection against lethal leptospirosis challenge in animal model. Microb Pathog 2020; 141:103975. [PMID: 31931114 DOI: 10.1016/j.micpath.2020.103975] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 12/30/2019] [Accepted: 01/10/2020] [Indexed: 01/04/2023]
Abstract
Leptospirosis is a widespread zoonotic disease caused by pathogenic spirochetes of the genus Leptospira. The commercially available vaccines are bacterins that offer limited protection, short-term effect, and serovar-specific immunity. The development of novel immunization strategies is crucial to control the infection and decrease the chances of new outbreaks. In this study, purified monoclonal antibodies (mAbs) anti-LipL32 (1D9 and mAb3) were evaluated by their capacity to bind and neutralize the pathogen improving host survival. For that, an in vitro growth inhibition assay, and in vivo passive immunization were performed in animal model. Syrian hamsters were passively immunized by three different strategies. Hamsters immunized with mAb3 6 h prior to the lethal challenge showed a significantly higher survival rate of 61.1%, and a significant reduction in tissue damage in the lungs. Cumulatively, our results showed that anti-LipL32 mAbs inhibited the growth of L. interrogans in vitro, and that passive immunization offered significant protection in animal model when administered prior to infection.
Collapse
Affiliation(s)
- Charles Klazer Gomes
- The University of Texas at Austin, Austin, TX, USA; Programa de Pós-graduação em Biotecnologia, Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Pelotas, RS, Brazil
| | - Violetta Dias Pacce
- Programa de Pós-graduação em Biotecnologia, Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Pelotas, RS, Brazil
| | - Natasha Rodrigues de Oliveira
- Programa de Pós-graduação em Biotecnologia, Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Pelotas, RS, Brazil
| | - Sérgio Jorge
- Programa de Pós-graduação em Biotecnologia, Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Pelotas, RS, Brazil.
| | - Thaís Farias Collares
- Programa de Pós-graduação em Biotecnologia, Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Pelotas, RS, Brazil
| | - Amilton Clair Pinto Seixas Neto
- Programa de Pós-graduação em Biotecnologia, Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Pelotas, RS, Brazil
| | - Marta Gonçalves Amaral
- Programa de Pós-graduação em Biotecnologia, Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Pelotas, RS, Brazil
| | - Odir Antônio Dellagostin
- Programa de Pós-graduação em Biotecnologia, Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Pelotas, RS, Brazil
| | - Daiane Drawanz Hartwig
- Programa de Pós-graduação em Biotecnologia, Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Pelotas, RS, Brazil; Departamento de Microbiologia e Parasitologia, Instituto de Biologia, Universidade Federal de Pelotas, RS, Brazil
| |
Collapse
|
8
|
Pissawong T, Maneewatchararangsri S, Ritthisunthorn N, Soonthornworasiri N, Reamtong O, Adisakwattana P, Kalambaheti T, Chaisri U, Doungchawee G. Immunodominance of LipL32 93-272 peptides revealed by leptospirosis sera and therapeutic monoclonal antibodies. JOURNAL OF MICROBIOLOGY, IMMUNOLOGY, AND INFECTION = WEI MIAN YU GAN RAN ZA ZHI 2018; 53:11-22. [PMID: 29500044 DOI: 10.1016/j.jmii.2017.12.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 10/30/2017] [Accepted: 12/12/2017] [Indexed: 12/01/2022]
Abstract
BACKGROUND/PURPOSE Leptospirosis is a neglected zoonosis, imposing significant human and veterinary public health burdens. In this study, recombinant LipL3293-147 and LipL32148-184 middle domain of LipL3293-184, and LipL32171-214, and LipL32215-272 of c-terminal LipL32171-272 truncations were defined for immunodominance of the molecule during Leptospira infections revealed by leptospirosis sera. RESULTS IgM-dominant was directed to highly surface accessible LipL32148-184 and Lipl32171-214. IgG dominance of LipL32148-184 revealed by rabbit anti-Leptospira sera and convalescent leptospirosis paired sera were mapped to highly accessible surface of middle LipL32148-184 truncation whereas two LipL32148-184 and LipL32215-272 truncations were IgG-dominant when revealed by single leptospirosis sera. The IgM-dominant of LipL32148-214 and IgG-dominant LipL32148-184 peptides have highly conserved amino acids of 70% identity among pathogenic and intermediate Leptospira species and were mapped to the highly surface accessible area of LipL32 molecule that mediated interaction of host components. IgG dominance of two therapeutic epitopes located at LipL32243-253 and LipL32122-130 of mAbLPF1 and mAbLPF2, respectively has been shown less IgG-dominant (<30%), located outside IgG-dominant regions characterized by leptospirosis paired sera. CONCLUSION The IgM- and IgG-dominant LipL32 could be further perspectives for immunodominant LipL32-based serodiagnosis and LipL32 epitope-based vaccine.
Collapse
Affiliation(s)
- Tippawan Pissawong
- Chulabhorn International College of Medicine, Thammasat University, Pathumthani 12120, Thailand
| | - Santi Maneewatchararangsri
- Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand.
| | - Nonglucksanawan Ritthisunthorn
- Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand
| | - Ngamphol Soonthornworasiri
- Department of Tropical Hygiene, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand
| | - Onrapak Reamtong
- Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand
| | - Poom Adisakwattana
- Department of Helminthology, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand
| | - Thareerat Kalambaheti
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand
| | - Urai Chaisri
- Department of Tropical Pathology, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand
| | - Galayanee Doungchawee
- Department of Pathobiology, Faculty of Science, Mahidol University, Bangkok 10400, Thailand
| |
Collapse
|
9
|
Shiokawa K, Gamage CD, Koizumi N, Sakoda Y, Shimizu K, Tsuda Y, Yoshimatsu K, Arikawa J. Evaluation of truncated LipL32 expressed by Escherichia coli and Pichia pastoris for serodiagnosis of Leptospira infection in rodents. J Vet Med Sci 2015; 78:221-30. [PMID: 26412049 PMCID: PMC4785110 DOI: 10.1292/jvms.15-0325] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The applicability of the recombinant LipL32 for serodiagnosis of leptospiral infection in field rodents was
assessed in this study. An immunodominant region of LipL32 was determined by monoclonal antibodies, and then,
truncated LipL32 (tLipL32) was designed to contain the region (87–188th amino acid). The tLipL32 was compared
between two recombinant expression hosts Escherichia coli and Pichia
pastoris in ELISA. With field rat sera, tLipL32 expressed by P. pastoris
(tLipL32p) had high antigenicity without background reactions, while tLipL32 expressed by E.
coli (tLipL32e) showed high background reactions, which were reduced by pre-adsorption of sera with
E. coli. To evaluate tLipL32-ELISA, field rat sera were tentatively divided into a
Leptospira infection positive (12 sera) and a negative group (12 sera) based on the results
from flaB gene PCR of kidney samples and WB with whole Leptospira cell.
Consequently, the sensitivity of tLipL32p-ELISA for field rat sera was 83% . A similar result was obtained
from tLipL32e-ELISA with adsorbed sera, (92%). However, sensitivity of tLipL32e-ELISA using sera without an
adsorption treatment was 50%. Regardless of the expression host, tLipL32-ELISA had 100% specificity and
sensitivity in experimentally infected laboratory rats. These results suggest that recombinant LipL32
expressed by P. pastoris is more applicable for serodiagnosis in field rats due to a lack of
background reaction.
Collapse
Affiliation(s)
- Kanae Shiokawa
- Department of Microbiology, Hokkaido University Graduate School of Medicine, Kita 15, Nishi 7, Kita-ku, Sapporo, Hokkaido 060-8638, Japan
| | | | | | | | | | | | | | | |
Collapse
|