Development of a novel reporter gene assay for platelet-derived growth factor-BB bioactivity

Platelet-derived growth factors (PDGFs) are involved in various physiological and pathological processes, making them important targets for drug development. However, current methods for measuring PDGF bioactivity do not meet the rapidly growing requirements of pharmaceutical research. Here, we describe a novel reporter gene assay (RGA) for PDGF-BB activity measurement. RGA was developed with engineered cells expressing a modified luciferase protein under the control of an SRE element. With PDGF-BB stimulation, cells produced stable dose-dependent signals with a correlation coefficient of R2 > 0.97 within several hours. The relative accuracy of the assay, represented by the relative bias for five independent samples with different bioactivity levels, was less than 4.67%. Variations in RGA caused by intra- and inter-assay factors were smaller than 10% and 15%, respectively. RGA not only yielded consistent results for estimating PDGF-BB activity, but also presented significantly lower variations than did the traditional colorimetric assay. Moreover, RGA could be completed within 2 days, showing a much higher efficiency than the WST method, which requires 4–5 days. Furthermore, RGA is suitable for other PDGF species besides PDGF-BB. Our results demonstrate that RGA could be a powerful tool for screening and identifying PDGF-related drug candidates in pharmaceutical applications.