Inflammatory gene expression in response to sub-lethal ricin exposure in Balb/c mice
TOXICOLOGY
Authors: David, Jonathan; Wilkinson, Lucy J.; Griffiths, Gareth D.
Abstract
The toxin ricin has been shown to cause inflammatory lung damage, leading to pulmonary oedema and, at higher doses, mortality. In order to understand the genetic basis of this inflammatory cascade a custom microarray platform (1509 genes) directed towards immune and inflammatory markers was used to investigate the temporal expression profiles of genes in a Balb/c mouse model of inhalational ricin exposure. To facilitate examination of those genes involved in both inflammatory cascades and wound repair the dose which was investigated was sub-lethal across a 96-h time course. Histopathology of the lung was mapped across the time course and genetic responses considered in the context of overall lung pathology. Six hundred and eighty-five genes were found to be statistically significantly different compared to controls, across the time course and these genes have been investigated in the context of their biological function in ricin poisoning. As well as confirming key inflammatory markers associated with ricin intoxication (TNF alpha and IL1 beta) several pathways that are altered in expression were identified following pulmonary exposure to ricin. These genes included those involved in cytokine-cytokine signalling cascades (IL1, IL1 r, IL1r2, Ccl4, 6, 10), focal adhesion (Fn1, ICAM1) and tissue remodelling (VEGF, Pim1). Furthermore, the observed alteration in expression of matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) indicates a key role in membrane integrity and cellular adhesion in ricin poisoning. Data captured using this transcriptomic approach could be used to develop a specific approach to the treatment of inhalational ricin exposure. This work was conducted as part of a wider programme of work to compare a number of militarily relevant lung damaging agents, with a view to establishing a rational basis for the identification of more generic medical countermeasures. Crown Copyright (C) 2009 Published by Elsevier Ireland Ltd. All rights reserved.
Molecular characterization and expression analysis of IL-1 beta and two types of IL-1 receptor in barbel steed (Hemibarbus labeo)
COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY B-BIOCHEMISTRY & MOLECULAR BIOLOGY
Authors: Zhou, Ning; Chen, Liang-Liang; Chen, Jie; Guo, Zhi-Ping
Abstract
Interleukin-1 beta (IL-1 beta) is a pivotal proinflammatory cytokine that plays important roles in regulating immune responses and in inducing a series of inflammatory reactions in response to infection. Recently, increasing attention has focused on the regulatory mechanisms of IL-1 beta activity in teleosts. In this regard, IL-1 receptor type 1 plays a crucial role in immune responses, whereas IL-1 receptor type 2 is a decoy receptor that functions as an IL-1 beta signaling inhibitor. However, the interactions of these three proteins with respect to fish immunity have rarely been studied. In the present study, cDNAs of the il1b, il1r1, and il1r2 genes of the barbel steed (Hemibarbus labeo) were cloned and sequenced. Amino acid sequence analysis revealed that the IL-1 beta protein and its two receptors identified in barbel steed are conserved in most teleosts, whereas phylogenetic tree analysis indicated that these three proteins are closely related to those of cyprinids. In response to lipopolysaccharide treatment, expression of the genes encoding IL-1 beta and its two receptors was significantly upregulated in the immune-related tissues of barbel steed. Furthermore, expression of the il1r1 and il1r2 genes was induced in monocytes/macrophages in response to stimulation with recombinant IL-1 beta