This will also allow better comparison of the urinary proteins as non-invasive biomarkers with the conventional plasma ALT measurements, including the predictive value for DILI. Continuous urine sample collection of patients with APAP-induced liver injury and DILI caused by other drugs is needed to assess further the suitability of the biomarkers suggested for acute DILI in general. In summary, using a translational approach we identified CA3, SOD1 and CaM as novel urinary biomarkers in relation to APAPinduced liver injury in both mouse and human urine GDC-0879 samples. These results allow further clinical validation to assess their applicability as non-invasive biomarkers for acute DILI. Fluorescent proteins are powerful tools to monitor cellular signals. Since the initial development of GFP as a research tool for biological discovery, laboratories have diversified FP spectra through directed evolution, resulting in a plethora of probes across the visible spectrum. These FPs have been used in the generation of fluorescence resonance energy transfer – based sensors to report dynamic biochemistry in living cells. Because FRET efficiency is sensitive to distance and orientation between the donor and acceptor fluorophore, conformational changes due to binding of a ligand to a protein of interest can form the basis of FRET-based biosensors. The most commonly used donor and acceptor FPs are variants of cyan FP and yellow FP. In recent years the development of alternate color FRET sensors has enabled new avenues of research such as the ability to monitor a single signal in multiple cellular compartments or simultaneously track two cellular signals. For example, two complementary probes for caspase-3 activity based on mTFP1/ mCitrine and mAmetrine/tdTomato were used to visualize caspase-3 activity in the nucleus and cytoplasm, revealing temporal differences in caspase-3 activation. The same FRET pairs were used to develop probes for monitoring both Ca2+ and caspase-3 in the same cell. Monomeric Teal FP is a FP version of the widely used CFP derived as a replacement for enhanced CFP because of its high quantum yield. Such studies allow researchers to precisely correlate the timing of two interdependent cellular events or to track the movement of ions or molecules from one compartment to another. An additional advantage of alternate color FRET sensors, particularly those that avoid using a variant of YFP which is quenched by acid, is that they are likely to be less sensitive to pH perturbations. While in principle the concept of generating alternate color FRET sensors is attractive, in practice there are a number challenges that have limited availability of non-CFP/YFP biosensors. First and foremost, the vast majority of the.120 FRET-based biosensors currently available are based on CFP/ YFP and as noted in a recent publication, changing the FPs often requires extensive re-optimization of the sensor. Secondly, the biophysical and photophysical properties of red and orange FPs still lag behind those of the cyan-yellow counterparts, making it challenging to identify a robust alternate FRET pair. Indeed of the non-CFP/YFP biosensors developed thus far, each research team chose a different combination of FRET partners. Prior to the time we concluded this study, there was no prospective randomized control trial to support the effectiveness and safety use of antiviral therapy in patients with ACHBLF. In addition, Lange et al reported that a significant portion of patients with high MELD scores and treated with entecavir developed lactic acidosis resulting in high mortality. Thus, the local standard of care at that time required a detailed discussion with patients and obtaining the consent prior to the antiviral use in patients with ACHBLF.