| Autor: |
Briscoe H; Department of Medicine, University of Sydney, NSW, Australia. hbriscoe@med.usyd.edu.au, Roach DR, Meadows N, Rathjen D, Britton WJ |
| Jazyk: |
angličtina |
| Zdroj: |
Journal of leukocyte biology [J Leukoc Biol] 2000 Oct; Vol. 68 (4), pp. 538-44. |
| Abstrakt: |
Tumor necrosis factor (TNF) is required to control mycobacterial infections, but its therapeutic value is limited by its in vivo instability and toxicity. The efficacy of a nontoxic TNF-mimetic peptide (TNF70-80) was tested in mice infected with Mycobacterium bovis bacillus Callette-Guerin (BCG). In vitro TNF70-80 and recombinant human TNF (hTNF) acted with interferon gamma (IFN-gamma) to reduce bacterial replication and to induce synthesis of bactericidal nitric oxide (NO) in BCG-infected, bone marrow-derived murine macrophages. The dose-dependent inhibitory effect on bacterial replication was blocked by neutralizing anti-IFN-gamma and anti-hTNF mAbs. Further, n-monomethyl-L-arginine (n-MMA) and a soluble TNF-receptor I (TNFRI-IgG) blocked bacterial growth and NO synthesis. Therefore, the peptide acted with IFN-gamma via induction of NO synthase and signaled through TNFRI receptors. Concomitant in vivo treatment with TNF70-80 or hTNF prevented reactivation of chronic BCG infection in mice depleted of CD4+ T cells by injecting anti-CD4 antibodies. Granuloma number and bacterial load were comparable in treated, T cell-depleted mice and in chronically infected, intact animals. Thus, TNF70-80 and hTNF can modulate recrudescent BCG infection in CD4+ T cell-deficient mice. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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