title: Development and evaluation of a rapid IgM capture ELISA (JEV-Chex) for the diagnosis of Japanese encephalitis.
abstract: BACKGROUND
  The IgM capture ELISA has been the most widely used diagnostic method for Japanese encephalitis. However, the lack of availability of validated commercial kits as well as the short shelf life of the kit reagents has limited the use of this technique to very few centres in Asia.
  
  
  OBJECTIVE
  Development and evaluation of a rapid IgM capture ELISA (JEV Chex) in comparison to the conventional IgM capture ELISA. Produce key reagents such as cell culture derived JEV antigen and biotinylated monoclonal antibody which are stable at room temperature.
  
  
  METHODS
  The conventional IgM capture ELISA was modified to reduce the total assay time and two key reagents used in the assay JEV antigen and biotinylated anti-JEV monoclonal antibodies were rendered stable at room temperature using a special procedure. A multi-centric evaluation of this rapid ELISA was carried out using well characterized stored CSF and serum samples. Long term stability of the key reagents was also assessed over a period of 6 months.
  
  
  RESULTS
  The rapid IgM capture ELISA developed by us showed complete concordance with the results obtained using the conventional ELISA at all the three centres where it was evaluated. In addition, the stability studies carried out with the inactivated cell culture antigen and the biotinylated monoclonal antibodies stored at room temperature for a period of 180 days revealed that both these reagents yielded consistent optical density values in the ELISA.
  
  
  CONCLUSIONS
  The rapid ELISA format of the IgM capture ELISA (JEV-Chex) developed by us as well as the stability of reagents achieved by us in this study is what renders this rapid IgM capture ELISA very robust and user friendly since reagents can be stored at 4 degrees C by peripheral labs.
authors.affiliation: Department of Neurovirology, National Institute of Mental Health and Neuro Sciences, Bangalore 560029, India. vravi@nimhans.kar.nic.in
authors.forename: V
authors.initials: V
authors.lastname: Ravi
authors.forename: A
authors.initials: A
authors.lastname: Desai
authors.forename: M
authors.initials: M
authors.lastname: Balaji
authors.forename: Madhuri P
authors.initials: MP
authors.lastname: Apte
authors.forename: Latha
authors.initials: L
authors.lastname: Lakshman
authors.forename: D K
authors.initials: DK
authors.lastname: Subbakrishna
authors.forename: G
authors.initials: G
authors.lastname: Sridharan
authors.forename: T N
authors.initials: TN
authors.lastname: Dhole
authors.forename: B V
authors.initials: BV
authors.lastname: Ravikumar
mesh_terms: D000330:Aedes; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D001769:Blood / Q000382:microbiology; D002460:Cell Line; D002555:Cerebrospinal Fluid / Q000821:virology; D004664:Encephalitis Virus, Japanese / Q000276:immunology*; D004672:Encephalitis, Japanese / Q000175:diagnosis* / Q000821:virology; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007075:Immunoglobulin M / Q000097:blood*; D051379:Mice; D013048:Specimen Handling / Q000379:methods; D013997:Time Factors
chemical_list: D000914:Antibodies, Viral; D007075:Immunoglobulin M