A Novel Fluorescent Probe for Real-Time In Vivo Imaging of LACTB Activity in Acute Lung Injury

Acute lung injury (ALI) are serious respiratory disorders marked by compromised gas exchange, inflammation, and excessive extracellular matrix (ECM) deposition. Current imaging techniques remain limited for early detection and monitoring of these diseases. This study introduces HD-LACTB , a near-infrared fluorescent probe developed by conjugating a LACTB-targeting unit with a structurally optimized hemicyanine dye. This probe demonstrates high specificity, sensitivity, rapid response, and enhanced deep-tissue imaging performance compared to existing agents. It also enables mitochondrial-targeted intracellular imaging, allowing real-time visualization of LACTB dynamics during ALI progression and treatment. In cellular models, HD-LACTB detected LACTB expression levels with fluorescence intensity corresponding to disease severity. In murine models, it non-invasively tracked therapeutic efficacy, supporting its utility for evaluating interventions. HD-LACTB addresses a critical need in early diagnosis by providing a sensitive, non-invasive tool for real-time monitoring of disease progression and treatment response, thereby facilitating improved clinical decision-making and patient outcomes.