In Vivo Bioimaging of RPE cell death

We have now demonstrated the ability to non‐invasively image RPE cell death in a targeted fashion with a custom engineered NIRF dye conjugated to an irreversibly binding pan‐caspase substrate. The bio‐probe detection was sensitive and specific for degenerating RPE and overlying outer retinal layers in a mouse model with geographic atrophy (GA)‐like features. No significant ocular toxicity was noted, and eyes maintained a clear visual axis with undetectable anterior or posterior segment inflammation. While the potential role of caspase inhibition in the treatment of GA remains uncertain and will be addressed in future studies, an ideal translation of this knowledge would be to utilize caspase imaging as a means for the early detection, prognosis, and indication for therapeutic intervention in GA.