Bio-Protocol (Dec 2014)

Fluorescence-linked Antigen Quantification (FLAQ) Assay for Fast Quantification of HIV-1 p24Gag

  • Marianne Gesner,
  • Mekhala Maiti,
  • Robert Grant,
  • Marielle Cavrois

DOI
https://doi.org/10.21769/BioProtoc.1366
Journal volume & issue
Vol. 4, no. 24

Abstract

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The fluorescence-linked antigen quantification (FLAQ) assay allows a fast quantification of HIV-1 p24Gag antigen. Viral supernatant are lysed and incubated with polystyrene microspheres coated with polyclonal antibodies against HIV-1 p24Gag and detector antibodies conjugated to fluorochromes (Figure 1). After washes, the fluorescence of microspheres is measured by flow cytometry and reflects the abundance of the antigen in the lysate. The speed, simplicity, and wide dynamic range of the FLAQ assay are optimum for many applications performed in HIV-1 research laboratories.