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Effect of non-tuberculous Mycobacteria on host biomarkers potentially relevant for tuberculosis management.

ABSTRACT: Non-tuberculous mycobacteria (NTM) are different from Mycobacterium tuberculosis (MTB) both in their ubiquitous environmental distribution and in their reduced capacity to cause disease. While often neglected in favour of other infectious diseases, NTM may interfere with important aspects of TB control and management, namely the efficacy of new anti-tuberculosis (TB) vaccines; the immuno-diagnostic Tuberculin skin test (TST) and QuantiFERON TB Gold In Tube assay (QFTGIT); and immune biomarkers explored for their diagnostic and/or predictive potential. Our objective was therefore to explore host immune biomarkers in children who had NTM isolated from respiratory and/or gastric specimens.The present study was nested within a prospective cohort study of BCG-vaccinated neonates in Southern India. In this setting, immune biomarkers from peripheral blood were analyzed in 210 children aged <3 years evaluated for TB using dual-colour-Reverse-Transcriptase-Multiple-Ligation-dependent-Probe-Amplification (dcRT-MLPA) and Bio-Plex assays. The children were classified based on clinical examination, chest X-rays and mycobacterial culture reports as either: 1) TB disease, 2) NTM present and 3) controls. The study shows a down-regulation of RAB33A (p<0.001) and up-regulation of TGF?1, IL-2 and IL-6 (all p<0.05) in children with TB disease, and that RAB33A, TGFBR2 and IL-10 (all p<0.05) were differentially expressed in children with NTM present when compared to children that were culture negative for MTB and NTM (controls).Carriage of NTM may reduce the specificity of future diagnostic and predictive immune biomarkers relevant to TB management.

SUBMITTER: Dhanasekaran S

PROVIDER: S-EPMC4199571 | biostudies-other | 2014 Oct

REPOSITORIES: biostudies-other

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Effect of non-tuberculous Mycobacteria on host biomarkers potentially relevant for tuberculosis management.

Dhanasekaran S S Jenum Synne S Stavrum Ruth R Wiker Harald G HG Kenneth John J Vaz Mario M Doherty T Mark TM Grewal Harleen M S HM

PLoS neglected tropical diseases 20141016 10

<h4>Background</h4>Non-tuberculous mycobacteria (NTM) are different from Mycobacterium tuberculosis (MTB) both in their ubiquitous environmental distribution and in their reduced capacity to cause disease. While often neglected in favour of other infectious diseases, NTM may interfere with important aspects of TB control and management, namely the efficacy of new anti-tuberculosis (TB) vaccines; the immuno-diagnostic Tuberculin skin test (TST) and QuantiFERON TB Gold In Tube assay (QFTGIT); and ...[more]

PMID: 25329719

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Dataset Information

Effect of non-tuberculous Mycobacteria on host biomarkers potentially relevant for tuberculosis management.

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Effect of non-tuberculous Mycobacteria on host biomarkers potentially relevant for tuberculosis management.

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