Non-depleted human plasma proteome of pulmonary tuberculosis

ABSTRACT: Novel biomarkers to identify infectious patients transmitting Mycobacterium tuberculosis are urgently needed to control the global tuberculosis (TB) pandemic. We hypothesized that proteins released into the plasma in active pulmonary TB are clinically useful biomarkers to distinguish TB cases from healthy individuals and patients with other respiratory infections. We applied a highly sensitive non-depletion tandem mass spectrometry discovery approach to investigate plasma protein expression in pulmonary TB cases compared to healthy controls in South African and Peruvian cohorts. . Plasma samples were analysed from 11 untreated male patients with active pulmonary TB and 10 male healthy control samples. Each plasma sample was initially separated into four segments by size exclusion chromatography, and each segment was processed individually. Analyses of plasma segments were performed in twelve iTRAQ (isobaric tags for relative and absolute quantification) 8-plex experimental sets in a block randomised design comprising three experimental sets. Each iTRAQ experiment contained a bridging master-pool plasma sample run in every experiment. Healthy controls were matched to TB samples by age, ethnicity, and smoking status within each iTRAQ set. Protein abundances from the plasma segments and multi-consensus reports were combined and adjusted for experimental batch effects. Protein abundances from the remaining combined plasma segment proteomes between experimental sets and the combined multi-consensus proteomes were analysed by complementary bioinformatic approaches to identify candidate diagnostic protein biomarkers. In total, 4,696 protein identifications were made across all iTRAQ experiments, at 5% FDR (false discovery rate). This comprised 2,332 unique host-derived proteins and 22 Mtb-derived proteins. Of these, 594 host proteins had a quantification result for every sample analysed and therefore comprised the complete quantified proteome. Subsequent bioinformatic analysis identified 118 differentially expressed proteins by three complementary bioinformatic pipelines and were taken forward in subsequent validation work as strong candidate biomarkers of pulmonary TB.

INSTRUMENT(S): Orbitrap Fusion, LTQ Orbitrap Elite

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Blood Plasma

DISEASE(S): Pulmonary Tuberculosis

SUBMITTER: Hannah Schiff  

LAB HEAD: Spiros Garbis

PROVIDER: PXD051070 | Pride | 2024-06-22

REPOSITORIES: Pride