Proteomic and transcriptomic host biomarkers for detection of pleural tuberculosis

Current diagnosis of pleural tuberculosis (PLTB) is based on highly invasive procedures. Therefore, blood-based host biomarkers could represent a low-invasive diagnostic alternative. In this study, we evaluated the capacity of previously identified blood-based host proteomic and transcriptomic biomarkers for pulmonary TB to discriminate PLTB from other pleural diseases (OPLD). Plasma and pleural effusion, as well as blood and pleural fluid mononuclear cells (PBMCs and PFMCs), were sampled from patients with PLTB and OPLDs. In pleural effusion, ApoA1, C1q, CRP, IL-6, IFN-γ, IP-10, MIG, S100A12, SAA1/A2, and serpin-A3 were significantly higher in PLTB compared to OPLD, whereas only SAA1/A2 showed discriminatory potential in plasma. Increased mRNA levels were observed in PFMCs of PLTB for CD8A, GBP5, SLAMF7, CXCL10, IL2, GNLY, IL23A, PDCD1 and BCMA, whereas HMOX1, CD163, DUSP3, IGF1, GUSB and MARCO were decreased. In PBMCs of PLTB, only CCL22 expression was decreased. GBP5 was significantly higher expressed in PLTB for both cell types. This study shows the potential of transcriptomic and proteomic host biomarkers to differentiate PLTB from OPLDs, also when applying low-invasive methods.