The output of each chemical-assay combination was reported in terms of either half-maximal activity concentration (AC50) or lowest effective concentration (LEC) at which there was a statistically significant change from the concurrent negative control.
These values were either half-maximal activity concentration (AC50) or lowest effective concentration (LEC) at which there was a statistically significant change from the concurrent negative control.
For each assay chemical combination, using automated curve fitting, we derived either an AC50 (half-maximal activity concentration) or LEC (lowest effective concentration, statistically significant change from controls), where a default value of 1 M was assigned for inactive chemicals.
The cell viability qHTS assays have been extensively validated and are known to give reproducible results [e.g., half-maximal activity concentration (AC50) values] in toxicity screening studies (Inglese et al. 2006; Xia et al. 2008).
This was true even when multiple molecular targets, including many with lower AC50 (half-maximal activity concentration) values than those related to reproduction, were affected (see Supplemental Material, Figures S1 S9), indicating that the most sensitive assay may not be driving the toxicity outcome.
Half-maximal activity concentrations (AC50) were identified for 729 chemicals in 256 assays (7,135 chemical assay pairs).
These values were half-maximal activity concentrations (AC50) for all assays except the multiplexed transcription factor assay, for which lowest effective concentrations (LECs) were calculated.
The activity for subsaturating concentrations of 17β-estradiol was expressed as percent of maximal activity with saturating concentrations of 17β-estradiol (10 nM).
The DINP-induced increase showed maximal activity at these concentrations and then decreased.
