Open AccessEndogenous Interleukin-18 Improves the Early Antimicrobial Host Response in Severe Melioidosis
Author(s) -
W. Joost Wiersinga,
Catharina W. Wieland,
Gerritje J. W. van der Windt,
Anita de Boer,
Sandrine Florquin,
Arjen M. Dondorp,
Nicholas Day,
Sharon J. Peacock,
Tom van der Poll
Publication year - 2007
Publication title -
infection and immunity
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.508
H-Index - 220
eISSN - 1070-6313
pISSN - 0019-9567
DOI - 10.1128/iai.00080-07
Subject(s) - melioidosis , burkholderia pseudomallei , biology , immunology , immune system , interferon gamma , pathogenesis , interleukin 10 , interleukin , cytokine , microbiology and biotechnology , bacteria , genetics
Melioidosis is caused by the soil saprophyte Burkholderia pseudomallei and is endemic in Southeast Asia. The pathogenesis of melioidosis is still largely unknown, although gamma interferon (IFN-gamma) seems to play an obligatory role in host defense. Previously, we have shown that IFN-gamma production in melioidosis is controlled in part by interleukin-18 (IL-18). The aim of the present study was to determine the role of IL-18 in the immune response to B. pseudomallei. For this the following investigations were performed. (i) Plasma IL-18 and blood monocyte IL-18 mRNA levels were elevated in 34 patients with culture-proven melioidosis compared to the levels in 32 local healthy controls; in addition, IL-18 binding protein levels were markedly elevated in patients, strongly correlating with mortality. (ii) IL-18 gene-deficient (IL-18 knockout [KO]) mice showed accelerated mortality after intranasal infection with a lethal dose of B. pseudomallei, which was accompanied by enhanced bacterial growth in their lungs, livers, spleens, kidneys, and blood at 24 and 48 h postinfection, compared to wild-type mice. In addition, IL-18 KO mice displayed evidence of enhanced hepatocellular injury and renal insufficiency. Together, these data indicate that the enhanced production of IL-18 in melioidosis is an essential part of a protective immune response to this severe infection.