Microfluidic Profiling of an Immune Cell‐Associated Extracellular Vesicle Signature for Active Tuberculosis Diagnosis and Treatment Monitoring

ABSTRACT

Rapid and accurate diagnosis of active tuberculosis (ATB) remains challenging, particularly in paucibacillary cases, where conventional pathogen detection often fails. Plasma extracellular vesicles carrying innate immune cell‐associated surface proteins, termed tuberculosis‐associated immune cell extracellular vesicles (TB‐IEVs), were investigated as biomarkers of ATB and integrated into a multichannel microfluidic platform. Whole‐blood transcriptome profiling of patients with ATB and healthy controls (HCs) enabled the systematic selection of four innate immune cell‐associated surface markers (RAB8A, TYROBP, C3AR1 and LILRA2). Marker validation using a bead‐based immunoprecipitation assay confirmed elevated TB‐IEV levels in ATB plasma. This signature was implemented on an 8‐channel microfluidic chip, enabling parallel fluorescence analysis of only 10 µL of plasma within 30 min. In a clinical cohort (25 patients with ATB and 24 HCs), the TB‐IEV multichannel chip achieved an area under the curve of 0.98. The signature also distinguished ATB from other respiratory diseases ( n  = 40) with an AUC of 0.95 and provided complementary diagnostic information in ATB patients with negative results on individual conventional tests. Longitudinal monitoring showed markedly decreased TB‐IEV levels following anti‐tuberculosis treatment. Collectively, this work demonstrated the potential of TB‐IEV profiling as a rapid, minimally invasive approach for ATB diagnosis and treatment monitoring.