Cell Line Description:
The ToxReporter Hmox1 Cell Line contains a reporter gene under transcriptional control of the Hemoxygenase Response Element (Hmox1) promoter. This reporter construct is stably integrated into the CHO cell line. The induction of a toxic response through the Hmox1 pathway results in the secretion of a reporter (ToxReporter) protein into the cell culture media. The secreted ToxReporter protein in the media can then be quantified using the ToxReporter ELISA kit. This cell line has been optimized for assay performance including plate seeding number, stimuli concentration for optimal response and stimulation time. Validations for assay performance include EC50 and Z’.

Pathway Description:
Virtually all toxic responses are preceded by the transcriptional activation of stress response pathways and many therapeutic responses involve downstream transcriptional events. The promoters of genes activated in this manner therefore have the potential to be used to provide early markers of response. The ToxReporter cell lines were stably transfected with a series of promoters that are used to drive reporters which are easily detectable in tissue culture medium. As a consequence, the ToxReporter cell lines allow the detection of early biomarkers of toxicity. In the Hmox1 ToxReporter engineered cell line, stress response induced by toxic agents leads to the activation of various transcription factors which then bind and activate the Hmox1 promoter.