Antisense phosphorothioate oligonucleotides to the p65 subunit of NF-kappaB abrogate fulminant septic shock induced by S. typhimurium in mice.

The aim of this study was to characterize the functional relevance of the transcription factor NF-kappaB in the pathogenesis of septic shock. BALB/c mice were infected with two wild-type (WT 1, WT 2) strains of S. typhimurium that induce NF-kappaB or an escape variant that lacks this ability (P21) at a dose of 1 x 109/animal, respectively. Furthermore, wild-type infected mice were treated with antisense oligonucleotides directed against NF-kappaB 24 h before and 3 or 6 h after infection, while mismatched oligonucleotides were used as controls. Subsequently, the clinical course, histological and immunological alterations were monitored. Infection with WT 1 and WT 2 strains led to lethal septic shock within 24-36 h. In contrast, infection with the P21 variant was not followed by fulminant septic shock. Treatment with specific antisense oligonucleotides against the p65 subunit of NF-kappaB 24 h before infection prevented the development of fulminant, lethal septic shock and was associated with a significant increase of survival. After 20 h, markedly depressed serum levels of interferon (IFN)-gamma and interleukin (IL)-6 but not IL-10 and tumour necrosis factor (TNF)-alpha were observed in p65 antisense-treated compared to mismatched-treated animals. These data show that the ability of S. typhimurium to induce lethal septic shock is critically dependent on their capacity to induce NF-kappaB.