A case study: development of a bioassay for IL-1ra

The IL-1ra bioassay was overhauled in 1993 at Synergen, Inc. The team included bioassay specialists and two pre-clinical statisticians. We began by focusing on the technical aspects, optimizing the number of cells per well, altering the staining procedure, and checking incubation times. We then proceeded to revise the layout of the dose-response curves on the 96-well plates and included an internal control as well as a standard. Finally, we reconfigured the statistical modelling procedure to model each plate as a whole using a 9-parameter logistic curve. When the work was concluded, the precision (%CV) had improved from 44% to 10%, while the retest rate was reduced from 20-30% to less than 5%.