Article

Engagement of Toll-like receptor 2 on CD4(+) T cells facilitates local immune responses in patients with tuberculous pleurisy.

Shenzhen Clinical Research Center for Infectious Diseases, Shenzhen Third Hospital, Shenzhen, China.
The Journal of Infectious Diseases (impact factor: 6.41). 07/2009; 200(3):399-408. DOI:10.1086/600075 pp.399-408
Source: PubMed

ABSTRACT Although it has been recognized that Mycobacterium tuberculosis contains large amounts of Toll-like receptor 2 (TLR2) ligands, their direct effects on CD4(+) T cells and the clinical implications have not been determined.
With the recent finding that activated CD4(+) T cells express TLR2 as a costimulatory receptor, we hypothesized that M. tuberculosis and its components may directly affect CD4(+) T cells by engaging TLR2, thus facilitating the expansion and function of these lymphocytes in tuberculous pleura.
Our results indicate that CD4(+) T cells from the pleural fluid and peripheral blood of patients with tuberculosis show significantly increased TLR2 expression, compared with those from healthy donors. TLR2 ligand activity was also significantly higher in the tuberculous pleural fluid than in the serum from healthy donors or patients with pulmonary tuberculosis. M. tuberculosis TLR2 ligands, 19-kDa lipoprotein, and live bacillus Calmette-Guérin all modulated cytokine production (interferon gamma and interleukin 17), cellular proliferation, survival, and migration of CD4(+) T cells isolated from pleural fluid and activated with anti-CD3 and anti-CD28.
These data indicate that direct interaction between M. tuberculosis TLR2 ligands and CD4(+) T cells facilitated local CD4(+) T cell immune responses in patients with tuberculous pleurisy.

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    Article: Molecular characterization of toll-like receptor 2 (TLR2), analysis of its inductive expression and associated down-stream signaling molecules following ligands exposure and bacterial infection in the Indian major carp, rohu (Labeo rohita).
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    Fish &amp Shellfish Immunology 12/2011; 32(3):411-25. · 3.32 Impact Factor
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.

Keywords

19-kDa lipoprotein
 
bacillus Calmette-Guérin
 
cellular proliferation
 
clinical implications
 
costimulatory receptor
 
direct effects
 
direct interaction
 
engaging TLR2
 
healthy donors
 
interleukin 17
 
large amounts
 
M. tuberculosis TLR2 ligands
 
modulated cytokine production
 
Mycobacterium tuberculosis
 
pleural fluid
 
TLR2
 
TLR2 expression
 
TLR2 ligand activity
 
Toll-like receptor 2
 
tuberculous pleural fluid