Differences in T‐cell responses between Mycobacterium tuberculosis and Mycobacterium africanum‐infected patients. Issue 5 (20th February 2014)

• Record Type: Journal Article
• Authors: Tientcheu, Leopold D.; Sutherland, Jayne S.; de, Bouke C.; Kampmann, Beate; Jafali, James; Adetifa, Ifedayo M.; Antonio, Martin; Dockrell, Hazel M.; Ota, Martin O.
• Is Part Of: European journal of immunology. Volume 44:Issue 5(2014:May)
• Page Start: 1387
• Page End: 1398
• Publication Date: 2014-02-20
• Subjects: Immunology -- Periodicals; 616.079
• DOI: 10.1002/eji.201343956
• Languages: English
• ISSNs: 0014-2980

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <p>In The Gambia, <italic>Mycobacterium tuberculosis</italic> (<italic>Mtb</italic>) and <italic>Mycobacterium africanum</italic> (<italic>Maf</italic>) are major causes of tuberculosis (TB). <italic>Maf</italic> is more likely to cause TB in immune suppressed individuals, implying differences in virulence. Despite this, few studies have assessed the underlying immunity to the two pathogens in human. In this study, we analyzed T‐cell responses from 19 <italic>Maf</italic>‐ and 29 <italic>Mtb</italic>‐infected HIV‐negative patients before and after TB chemotherapy following overnight stimulation of whole blood with TB‐specific antigens. Before treatment, percentages of early secreted antigenic target‐6(ESAT‐6)/culture filtrate protein‐10(CFP‐10) and purified protein derivative‐specific single‐TNF‐α‐producing CD4<sup>+</sup> and CD8<sup>+</sup> T cells were significantly higher while single‐IL‐2‐producing T cells were significantly lower in <italic>Maf</italic>‐ compared with <italic>Mtb</italic>‐infected patients. Purified protein derivative‐specific polyfunctional CD4<sup>+</sup> T cells frequencies were significantly higher before than after treatment, but there was no difference between the groups at both time points. Furthermore, the proportion of CD3<sup>+</sup>CD11b<sup>+</sup> T cells was similar in both groups pretreatment, but was significantly lower with higher TNF‐α, IL‐2, and IFN‐γ production in <italic>Mtb</italic>‐ compared with that of <italic>Maf</italic>‐infected patients posttreatment. Our data provide evidence of differences in T‐cell responses to two mycobacterial strains with differing virulence, providing some insight into TB pathogenesis with different <italic>Mtb</italic> strains that could be prospectively explored as biomarkers for TB protection or susceptibility.</p> </abstract>