To test the hypothesis that PCLs would increase confidence in biological interpretation, we profiled 137 test compounds known to share a mechanism with one or more of 54 small molecule PCLs, but which were not used in the construction of the PCL. For 41/54 classes (76%), the test compounds connected to their designated PCL in multiple cell types (Figure 4B). For an additional 7/54 (13%), a selective connection was observed in a single cell type. The remaining 6/54 (11%) did not connect at a threshold of τ >90.
