Evaluation of a Range of Anti-Proliferative Assays for the Preclinical Screening of Anti-Psoriatic Drugs: A Comparison of Colorimetric and Fluorimetric Assays with the Thymidine Incorporation Assay

Abstract Established treatments for psoriasis are generally based on anti-proliferative, anti-inflammatory, or differentiation-modifying activity, or a combination of these effects. New agents for the treatment of psoriasis could be identified by high-throughput screening (HTS) of large compound libraries using keratinocyte proliferation models. Although several new proliferation assays have been developed, the radioactive [3H]-thymidine incorporation assay is still considered to be the gold standard for the evaluation of keratinocyte proliferation in vitro. In this study, we compare a number of simple, and reliable, colorimetric (MTT, NRU, SRB, and CVS), and fluorimetric (CAM and AB) methods with the [3H]-thymidine incorporation assay for the measurement of keratinocyte proliferation in the exponential growth phase in 96-well formats. The concentrations that induced 50% growth inhibition (GI50) were determined by each assay for the established antipsoriatics, dithranol, and methotrexate. Strong correlati...