Comparison of a Micro-Neutralization Test with the Rapid Fluorescent Focus Inhibition Test for Measuring Rabies Virus Neutralizing Antibodies

Details

• Alternative Title:
  Trop Med Infect Dis
• Personal Author:
  Smith, Todd G. ; Gilbert, Amy T.
• Description:
  The rapid fluorescent focus inhibition test (RFFIT) is routinely used in the United States to measure rabies virus neutralizing antibodies (rVNA). RFFIT has a long history of reproducible and reliable results. The test has been modified over the years to use smaller volumes of reagents and samples, but requires a 50 μL minimum volume of test serum. To conduct pathogenesis studies, small laboratory animals such as mice are regularly tested for rVNA, but the minimum volume for a standard RFFIT may be impossible to obtain, particularly in scenarios of repeated sampling. To address this problem, a micro-neutralization test was developed previously. In the current study, the micro-neutralization test was compared to the RFFIT using 129 mouse serum samples from rabies vaccine studies. Using a cut-off value of 0.1 IU/mL, the sensitivity, specificity, and concordance of the micro-neutralization test were 100%, 97.5%, and 98%, respectively. The geometric mean titer of all samples above the cut-off was 2.0 IU/mL using RFFIT and 3.4 IU/mL using the micro-neutralization test, indicating that titers determined using the micro-neutralization test are not equivalent to RFFIT titers. Based on four rVNA-positive hamster serum samples, the intra-assay coefficient of variability was 24% and inter-assay coefficient of variability was 30.4 %. These results support continued use of the micro-neutralization test to determine rabies virus neutralizing antibody titers for low-volume serum samples.
• Keywords:
  Assay Development Assay Validation Diagnostic Test Rabies Virus Neutralizing Antibodies
• Source:
  Trop Med Infect Dis. 2(3)
• Pubmed ID:
  28845465
• Pubmed Central ID:
  PMC5568636
• Document Type:
  Journal Article
• Funding:
  CC999999/Intramural CDC HHSUnited States/
• Volume:
  2
• Issue:
  3
• Collection(s):
  CDC Public Access
• Main Document Checksum:
  urn:sha-512:d9ad83d0f872734e37e80b081be38782de155f51ffece0b6ff6b7ec0577e481a47ebd36a23fc42661129fc5626fbcc81bb8eb2ac5864375bd326bbd3b1349077
• Download URL:
  https://stacks.cdc.gov/view/cdc/48177/cdc_48177_DS1.pdf
• File Type:
  [PDF - 366.09 KB ]