title: Evaluation of a monoclonal antibody-based dot-blot ELISA for detection of Leptospira spp in bovine urine samples.
abstract: OBJECTIVE
  To evaluate the efficacy of a novel monoclonal antibody (MAb)-based dot-blot ELISA for detection of Leptospira antigens in urine samples of cattle.
  
  
  METHODS
  Blood and urine samples of 45 test cattle from 5 farms in Chonburi province and 20 control cattle from 2 farms in Khon Kaen province in Thailand.
  
  
  METHODS
  Blood and urine samples were assayed (microscopic agglutination test and urine antigen test) for Leptospira infection by use of an MAb-based dot-blot ELISA, and results for the ELISA were compared with those for dark-field microscopy (DFM), microbial culture, and a polymerase chain reaction (PCR) assay.
  
  
  RESULTS
  All urine samples with positive results for DFM, microbial culture, PCR assay, or > 1 of these tests also had positive results when tested by use of the MAb-based dot-blot ELISA, except for 1 sample that had positive results only for the PCR assay. Detection limits of the dot-blot ELISA were 10(3) leptospires/mL of urine and 9.3 ng of Leptospira homogenate. Comparison revealed that the diagnostic sensitivity, specificity, efficacy (accuracy), positive predictive value, and negative predictive value for the ELISA were in agreement with results for DFM (100%, 72.72%, 80%, 57.14%, and 100%, respectively), microbial culture (100%, 61.54%, 66.62%, 28.57%, and 100%, respectively), and PCR assay (95.45%, 100%, 91.77%, 100%, and 95.83%, respectively).
  
  
  CONCLUSIONS
  The MAb-based dot-blot ELISA is suitable as a tool for detecting leptospires in urine samples of cattle.
authors.affiliation: Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
authors.forename: Junpen
authors.initials: J
authors.lastname: Suwimonteerabutr
authors.forename: Wanpen
authors.initials: W
authors.lastname: Chaicumpa
authors.forename: Patcharin
authors.initials: P
authors.lastname: Saengjaruk
authors.forename: Pramuan
authors.initials: P
authors.lastname: Tapchaisri
authors.forename: Manas
authors.initials: M
authors.lastname: Chongsa-nguan
authors.forename: Thareerat
authors.initials: T
authors.lastname: Kalambaheti
authors.forename: Pongrama
authors.initials: P
authors.lastname: Ramasoota
authors.forename: Yuwaporn
authors.initials: Y
authors.lastname: Sakolvaree
authors.forename: Prachin
authors.initials: P
authors.lastname: Virakul
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D002417:Cattle; D002418:Cattle Diseases / Q000175:diagnosis* / Q000382:microbiology; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods* / Q000662:veterinary; D005260:Female; D015151:Immunoblotting / Q000379:methods* / Q000662:veterinary; D007919:Leptospira / Q000302:isolation & purification*; D007922:Leptospirosis / Q000097:blood / Q000652:urine / Q000662:veterinary*; D008297:Male; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D000911:Antibodies, Monoclonal