Comment

There are a number of reasons why this paper is of interest toGut readers. Firstly it provides new insights into the regulation of the proinflammatory cytokine tumour necrosis factor (TNF); secondly it shows that dysregulation of the TNF gene in mice leads to chronic inflammation of the joints and intestine; and thirdly there is evidence of differential roles for TNF receptors and the acquired immune response in joint and gut pathology. In addition, a useful mouse model of Crohn’s disease is described.

Stability and translation of mRNA is driven by specific elements in mRNA sequences. One major class consists of adenosine-uracil multimers called AU-rich elements (ARE) which map to the 3′ untranslated region (UTR) of many cytokine, oncoprotein and transcription factor transcripts. Alterations in the pattern of TNF production are associated with some diseases and the importance of TNF in rheumatoid arthritis and Crohn’s disease has been demonstrated …