Neutrophil degranulation, NETosis and platelet degranulation pathway genes are co-induced in whole blood up to six months before tuberculosis diagnosis
Data Availability: The full datasets can be obtained from the Gene Expression Omnibus (GEO; https://www.ncbi.nlm.nih.gov/geo/) as GSE94438 (https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE94438) and GSE89403 (https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE89403). These details are also provided in the Methods. Additional data on PET-CT scores accompany the revised document as S1 Table (https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0278295#pone.0278295.s001).The authors acknowledge the Centre for High Performance Computing (CHPC), South Africa, for providing computational resources to this research project.Mycobacterium tuberculosis (M.tb) causes tuberculosis (TB) and remains one of the leading causes of mortality due to an infectious pathogen. Host immune responses have been implicated in driving the progression from infection to severe lung disease. We analyzed longitudinal RNA sequencing (RNAseq) data from the whole blood of 74 TB progressors whose samples were grouped into four six-month intervals preceding diagnosis (the GC6-74 study). We additionally analyzed RNAseq data from an independent cohort of 90 TB patients with positron emission tomography-computed tomography (PET-CT) scan results which were used to categorize them into groups with high and low levels of lung damage (the Catalysis TB Biomarker study). These groups were compared to non-TB controls to obtain a complete whole blood transcriptional profile for individuals spanning from early stages of M.tb infection to TB diagnosis. The results revealed a steady increase in the number of genes that were differentially expressed in progressors at time points closer to diagnosis with 278 genes at 13–18 months, 742 at 7–12 months and 5,131 detected 1–6 months before diagnosis and 9,205 detected in TB patients. A total of 2,144 differentially expressed genes were detected when comparing TB patients with high and low levels of lung damage. There was a large overlap in the genes upregulated in progressors 1–6 months before diagnosis (86%) with those in TB patients. A comprehensive pathway analysis revealed a potent activation of neutrophil and platelet mediated defenses including neutrophil and platelet degranulation, and NET formation at both time points. These pathways were also enriched in TB patients with high levels of lung damage compared to those with low. These findings suggest that neutrophils and platelets play a critical role in TB pathogenesis, and provide details of the timing of specific effector mechanisms that may contribute to TB lung pathology.SM, EM, GT and GW were supported by the South African Tuberculosis Bioinformatics Initiative (SATBBI), a Strategic Health Innovation Partnership grant from the South African Medical Research Council (https://www.samrc.ac.za/) and South African Department of Science and Innovation (https://www.dst.gov.za/); no grant number. STM received funding from the EDCTP2 program (Grant Number CDF1576) supported by the European Union (http://www.edctp.org/projects-2/#). GW received funding from the South African National Research Foundation (SARChI TB Biomarkers #86535) and the South African Medical Research Council (https://www.samrc.ac.za/). SHEK, TJS and GW received funding from the Bill and Melinda Gates Foundation (Grant Numbers OPP37772 & OPP1055806), (https://www.gatesfoundation.org/) GW received funding from the Bill and Melinda Gates Foundation (Grant Number OPP51919) (https://www.gatesfoundation.org/) through the Catalysis Foundation for Health (https://catalysisfoundation.org/) AGL is supported by the NRF-CSUR (Grant Number CSUR60502163639) and by the Centre for Tuberculosis Research from the South African Medical Research Council (https://www.samrc.ac.za/). JAS is supported by a Clinician Scientist Fellowship (Grant Number MR/R007942/1) jointly funded by the UK Medical Research Council (MRC; https://www.ukri.org/about-us/mrc/) and the UK Department for International Development [DFID; replaced by Foreign, Commonwealth & Development Office (FCDO); https://www.gov.uk/government/organisations/foreign-commonwealth-development-office] under the MRC/DFID Concordat agreement
