The death-promoting molecule tumour necrosis factor-related apoptosis inducing ligand (TRAIL) is not required for the development of peripheral lymphopenia or granuloma necrosis during infection with virulent Mycobacterium avium

• Type: Article in International Scientific Journal
• Date: 2011

Authors

Borges, M (Author) FFUP; Rosa, GT (Author) Other; Appelberg, R (Author) ICBAS

Journal

Title: Clinical and Experimental Immunology

Vol. 164

Pages: 407-416

ISSN: 0009-9104

Publisher: Wiley-Blackwell

Indexing

ISI Web of Knowledge - 2 Citations

Scopus - 4 Citations

Scientific classification

FOS: Medical and Health sciences > Basic medicine

Other information

Authenticus ID: P-002-R9H

DOI: 10.1111/j.1365-2249.2011.04385.x

Abstract (EN): P>Disseminated infection with virulent Mycobacterium avium in C57Bl/6 (B6) mice leads to severe lymphocyte depletion in secondary lymphoid organs. In this study, we found an up-regulation of caspase-8 activity in spleen cell extracts from M. avium 25291-infected B6 mice compared to non-infected mice. The activation of this extrinsic apoptotic pathway correlated with an increase in inter-nucleosomal DNA fragmentation in CD4+ spleen cells, as analysed by the terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) assay. These data suggest the involvement of death receptors in the induction of lymphocyte loss in the spleen, but previous work has excluded a role for tumour necrosis factor (TNF) receptors and Fas/CD95 in M. avium-induced lymphopenia. TNF-related apoptosis-inducing ligand (TRAIL) is expressed by different cell types of the immune system and induces apoptosis and killing of tumour cells while sparing normal cells. Here we used TRAIL-/- mice to determine if the absence of TRAIL prevented M. avium-induced immune pathology. We found that TRAIL-deficient mice still developed splenic lymphopenia during disseminated infection or granuloma necrosis during low-dose infections while exhibiting slightly increased susceptibility to M. avium 25291 when compared to B6 mice. However, in vivo proliferation of less virulent strains of M. avium was not influenced by TRAIL deficiency despite a decrease in interferon-gamma production in infected B6.TRAIL-/- mice compared to B6 mice. Our results show that TRAIL does not play a significant role in either M. avium-induced pathology or protective immunity.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10