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Interleukin-6: a potent biomarker of mycobacterial infection

BACKGROUND: Human tuberculosis (TB), a chronic inflammatory disease is caused by Mycobacterium tuberculosis, a facultative intramacrophage pathogen. The highly complex interactions between mycobacteria and macrophages (MΦs), characterized in part by the induction and elaboration of several cytokines...

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Autores principales: Singh, Prati Pal, Goyal, Amit
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Springer International Publishing 2013
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3893321/
https://www.ncbi.nlm.nih.gov/pubmed/24455461
http://dx.doi.org/10.1186/2193-1801-2-686
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author Singh, Prati Pal
Goyal, Amit
author_facet Singh, Prati Pal
Goyal, Amit
author_sort Singh, Prati Pal
collection PubMed
description BACKGROUND: Human tuberculosis (TB), a chronic inflammatory disease is caused by Mycobacterium tuberculosis, a facultative intramacrophage pathogen. The highly complex interactions between mycobacteria and macrophages (MΦs), characterized in part by the induction and elaboration of several cytokines including IL-1, IL-6, IL-10, IL-12 p40 and IL-12 p70 are not yet fully understood. The cytokines are known to have important bearing on the pathogenesis and host defense during TB. We thus studied different patterns of cytokines elaborated by mouse peritoneal macrophages (PMs) following their interaction with live and heat-killed, virulent and avirulent, and pathogenic and non-pathogenic mycobacteria, in vitro. MATERIALS AND METHODS: Pathogenic M. tuberculosis H37Rv (virulent) and M. tuberculosis H37Ra (avirulent), and non-pathogenic M. smegmatis were grown in complete Middle Brook 7H9 broth. For some experiments, mycobacteria were heat-killed (80°C; 20 min). The supernatants of cultured PMs, having ingested mycobacteria for 6 h, 24 h, 4 days and 7 days, were harvested for the quantification of IL-1, IL-6, IL-10, IL-12 p40 and IL-12 p70 by using a multiplex suspension cytokine array system. RESULTS: The PMs infected with heat-killed mycobacteria, as compared to their respective live counterparts, invariably elaborated significantly (p < 0.001) increased (approximately 2–3-fold) amounts of IL-6, at all the time-points studied, in vitro. Further, PMs infected with M. tuberculosis H37Ra, as compared to M. tuberculosis H37Rv, elaborated 4–5-fold more (p < 0.001) IL-6. Non-pathogenic M. smegmatis, as compared to pathogenic M. tuberculosis H37Ra and M. tuberculosis H37Rv, following infection, induced the PMs to elaborate highest (p < 0.001) amounts of IL-6 at all the time-points studied. Curiously, none of these mycobacteria-infected PMs elaborated IL-1, IL-10, IL-12 p40 and IL-12 p70, significantly. CONCLUSION: IL-6 appears to be the only major cytokine elaborated by mycobacteria-infected PMs, in vitro, and thus may function as a potent biomarker of mycobacterial infection, either stand-alone or along with other cytokines.
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spelling pubmed-38933212014-01-22 Interleukin-6: a potent biomarker of mycobacterial infection Singh, Prati Pal Goyal, Amit Springerplus Research BACKGROUND: Human tuberculosis (TB), a chronic inflammatory disease is caused by Mycobacterium tuberculosis, a facultative intramacrophage pathogen. The highly complex interactions between mycobacteria and macrophages (MΦs), characterized in part by the induction and elaboration of several cytokines including IL-1, IL-6, IL-10, IL-12 p40 and IL-12 p70 are not yet fully understood. The cytokines are known to have important bearing on the pathogenesis and host defense during TB. We thus studied different patterns of cytokines elaborated by mouse peritoneal macrophages (PMs) following their interaction with live and heat-killed, virulent and avirulent, and pathogenic and non-pathogenic mycobacteria, in vitro. MATERIALS AND METHODS: Pathogenic M. tuberculosis H37Rv (virulent) and M. tuberculosis H37Ra (avirulent), and non-pathogenic M. smegmatis were grown in complete Middle Brook 7H9 broth. For some experiments, mycobacteria were heat-killed (80°C; 20 min). The supernatants of cultured PMs, having ingested mycobacteria for 6 h, 24 h, 4 days and 7 days, were harvested for the quantification of IL-1, IL-6, IL-10, IL-12 p40 and IL-12 p70 by using a multiplex suspension cytokine array system. RESULTS: The PMs infected with heat-killed mycobacteria, as compared to their respective live counterparts, invariably elaborated significantly (p < 0.001) increased (approximately 2–3-fold) amounts of IL-6, at all the time-points studied, in vitro. Further, PMs infected with M. tuberculosis H37Ra, as compared to M. tuberculosis H37Rv, elaborated 4–5-fold more (p < 0.001) IL-6. Non-pathogenic M. smegmatis, as compared to pathogenic M. tuberculosis H37Ra and M. tuberculosis H37Rv, following infection, induced the PMs to elaborate highest (p < 0.001) amounts of IL-6 at all the time-points studied. Curiously, none of these mycobacteria-infected PMs elaborated IL-1, IL-10, IL-12 p40 and IL-12 p70, significantly. CONCLUSION: IL-6 appears to be the only major cytokine elaborated by mycobacteria-infected PMs, in vitro, and thus may function as a potent biomarker of mycobacterial infection, either stand-alone or along with other cytokines. Springer International Publishing 2013-12-21 /pmc/articles/PMC3893321/ /pubmed/24455461 http://dx.doi.org/10.1186/2193-1801-2-686 Text en © Singh and Goyal; licensee Springer. 2013 This article is published under license to BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
spellingShingle Research
Singh, Prati Pal
Goyal, Amit
Interleukin-6: a potent biomarker of mycobacterial infection
title Interleukin-6: a potent biomarker of mycobacterial infection
title_full Interleukin-6: a potent biomarker of mycobacterial infection
title_fullStr Interleukin-6: a potent biomarker of mycobacterial infection
title_full_unstemmed Interleukin-6: a potent biomarker of mycobacterial infection
title_short Interleukin-6: a potent biomarker of mycobacterial infection
title_sort interleukin-6: a potent biomarker of mycobacterial infection
topic Research
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3893321/
https://www.ncbi.nlm.nih.gov/pubmed/24455461
http://dx.doi.org/10.1186/2193-1801-2-686
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