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, particularly in the early stages. Herein, we begin with a comprehensive bioinformatics analysis, identifying neutrophils as key effectors in pneumonia pathogenesis, and neutrophil elastase (NE) as a critical biomarker associated with pneumonia progression. We subsequently develop a 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 active targeting responsive probes (ATRP _H ). ATRP _H demonstrate exceptional sensitivity and specificity in both in vivo imaging and urine-based detection, with urine analysis offering a non-invasive, early-stage diagnostic option that overcomes the limitations of tissue penetration and low accuracy associated with traditional imaging modalities. Additionally, ATRP _H is highly effective in drug screening, dosage optimization, and exploring mechanisms of NE production, which offers valuable insights into therapeutic efficacy. Moreover, NERP can also be prepared into liposomes (ATRP _L ) and membrane doped (ATRP _M ) nanoparticles through formulation optimization, and used for systemic inflammation detection through intravenous administration. 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, marking a significant advancement in precision medicine.