title: [Establishment of indirect immunofluorescence assay (IFA) for detection of IgG antibody against new bunyavirus].
abstract: OBJECTIVE
  To develop an indirect immunofluorescence assay (IFA) for detection of IgG antibodies against new bunyavirus.
  
  
  METHODS
  The antigen slides were prepared with 5 new bunyavirus strains isolated using Africa green monkey kidney (Vero) cells. Specificity and sensitivity evaluation of IFA were carried out by optimizing working conditions of IFA. Using established IFA, serum samples from both acute and recovery phases were tested for 126 cases with fever thrombocytopenia and leukopenia syndrome in Xinyang, Henan province in 2007 - 2011. The results were compared with detections by RT-PCR.
  
  
  RESULTS
  The new bunyavirus stable immunofluorescence specific WZ69 strain was selected to prepare antigen slides of IFA. The optimum conditions of IFA were: optimum dilution for primary antibody (serum) and secondary antibody (isosulfocyanic acid fluorescence marked goat anti-human IgG antibody) was 1:40 and 1:150 respectively. The optimum dilution for Evans blue in secondary antibody was 1:20 000. Among the 126 patients, 96 paired serum specimens were tested positive to the new bunyavirus and 30 patients were tested negative to the virus. The positive rate of antibodies was 76.19%. There was no significant difference in results between IFA and RT-PCR (72.22% (91/126)) (P > 0.05).
  
  
  CONCLUSIONS
  The IFA has high sensitivity and specificity with easy operation. It can be used in detecting the new bunyavirus infection in patients with fever, thrombocytopenia and leukopenia syndrome.
authors.affiliation: Institute for Infectious Disease Control and Prevention, Henan Provincial Center for Disease Control and Prevention, Zhengzhou 450016, China.
authors.forename: Xue-Yong
authors.initials: XY
authors.lastname: Huang
authors.forename: Yan-Hua
authors.initials: YH
authors.lastname: DU
authors.forename: Xing-le
authors.initials: XL
authors.lastname: Li
authors.forename: Hong
authors.initials: H
authors.lastname: Ma
authors.forename: Rui-Qin
authors.initials: RQ
authors.lastname: Man
authors.forename: Kai
authors.initials: K
authors.lastname: Kang
authors.forename: Xiao-Yan
authors.initials: XY
authors.lastname: Tang
authors.forename: Hao-Min
authors.initials: HM
authors.lastname: Chen
authors.forename: Guo-Hua
authors.initials: GH
authors.lastname: Liu
authors.forename: Bian-Li
authors.initials: BL
authors.lastname: Xu
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000032:analysis* / Q000276:immunology; D002044:Bunyaviridae Infections / Q000175:diagnosis / Q000276:immunology; D002522:Chlorocebus aethiops; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis* / Q000276:immunology; D008297:Male; D008875:Middle Aged; D016851:Orthobunyavirus / Q000276:immunology / Q000302:isolation & purification*; D012680:Sensitivity and Specificity; D014709:Vero Cells
chemical_list: D000914:Antibodies, Viral; D007074:Immunoglobulin G