Aberrant collagen production can lead to many diseases such as fibrosis. Current methods of collagen detection are insensitive, time-consuming and laborious. We have developed a rapid, sensitive assay using chemiluminescence-based reporter cell system. Stable 3T3/NIH-SMAD-luciferase cells were generated for detection of collagen expression through TGF-beta signaling, a major fibrogenic pathway. We demonstrated that these reporter cells could be used as a rapid screening tool for detection of SMAD-dependent collagen production with higher sensitivity than existing assays. Flexibility of this cell-based assay in different detection platforms makes it attractive for high throughput screening of potential fibrogenic agents and drug candidates. (C) 2014, The Society for Biotechnology, Japan. All rights reserved.