Proteomic profiling of eccrine sweat reveals its potential as a diagnostic biofluid for active tuberculosis

Purpose: Excessive sweating is a common symptom of the disease and an unexplored biofluid for TB diagnosis; we conducted a proof-of-concept study to identify potential diagnostic biomarkers of active TB in eccrine sweat. Experimental design: We performed a global proteomic profile of eccrine sweat sampled from patients with active pulmonary TB, other lung diseases (non-TB disease), and healthy controls. A comparison of proteomics between Active-TB, Non-TB, and Healthy Controls was done in search for potential biomarkers of active TB. Results: Sweat specimens were pooled from 32 active TB patients, 27 patients with non-TB diseases, and 24 apparently healthy controls, all were negative for HIV. Over 100 unique proteins were identified in the eccrine sweat of all three groups. Twenty-six proteins were exclusively detected in the sweat of patients with active TB while the remaining detected proteins overlapped between three groups. Gene ontology evaluation indicated that the proteins detected uniquely in sweat of active TB patients were involved in immune response and auxiliary protein transport. Gene products for cellular components (e.g. ribosomes) were detected only in active TB patients. Data are available via ProteomeXchange with identifier PXD003224. Conclusions and clinical relevance: Proteomics of sweat from active TB patients is a viable approach for biomarker identification, which could be used to develop a nonsputum-based test for detection of active TB.