Disease landscape–guided design of neutrophil-specific reporters for early and accurate pneumonia detection in vivo and in urine

Accurate and early detection of pneumonia is crucial for effective treatment; however, current diagnostic methods often lack the necessary specificity and sensitivity. Herein, we begin with a comprehensive bioinformatics analysis, identifying neutrophil elastase (NE) as a critical biomarker associated with pneumonia progression. We subsequently develop an NE-responsive probe (NERP), composed of a hemicyanine fluorophore linked to an NE-sensitive peptide, specifically designed for activation in inflamed tissues. To facilitate urinalysis, NERP is further refined into a hydrophilic active targeting responsive probe (ATRP H ). ATRP H demonstrates exceptional sensitivity in both in vivo imaging and urine-based detection, with urine analysis offering a noninvasive, early-stage diagnostic option that overcomes the limitations of tissue penetration and low accuracy. In addition, ATRP H is highly effective in drug screening, dosage optimization, and exploring mechanisms of NE production. This biomarker screening and design strategy not only enhances pneumonia diagnosis and treatment via different routes of administration but also has broader potential for other inflammatory lung diseases.