The mRNA level of the transforming growth factor β1 gene, but not the amount of the gene product, can be considered as a potential prognostic parameter in inflammatory bowel diseases in children

PURPOSE: Transforming growth factor β1 (TGF-β1) plays a role in cell proliferation and differentiation, and it can modulate immune response. In this work, we asked whether levels of either TGF-β1 or mRNA of the corresponding gene in plasma or tissue can be useful in diagnosing and/or monitoring of the clinical course of inflammatory bowel diseases (IBD). METHODS: The study group consisted of 104 pediatric patients with IBD: 36 with Crohn’s disease (CD) and 68 with ulcerative colitis (UC); 42 children represented the control group. TGF-β1 levels in plasma and intestinal mucosa were estimated by ELISA and immunohistochemistry (IHC), respectively. Levels of TGF-β1 mRNA were determined by reverse transcription and real-time PCR. RESULTS: In patients with IBD, and in subgroups with CD and UC, no significant differences in the TGF-β1 level in plasma and tissue were found relative to the control group. These variables were not dependent on the stage of the disease, its activity or severity of endoscopic and histopathological findings. TGF-β1 mRNA levels were significantly higher in tissue samples withdrawn during the relapse of the disease than in those taken during the remission or in the control group. However, no correlation between TGF-β1 plasma levels and TGF-β1 mRNA amount in the intestinal mucosa was observed. CONCLUSIONS: The TGF-β1 mRNA level, but not the amount of the gene product, was significantly increased in the pathologically changed tissue during the relapse of IBD. We suggest that this parameter might be considered as a potential prognostic value when assessing IBD in children. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00384-012-1489-4) contains supplementary material, which is available to authorized users.