Relevance of transforming growth factor-beta1, interleukin-8, and tumor necrosis factor-alpha polymorphisms in patients with chronic pancreatitis.

UNLABELLED: Cytokine regulation may be an important factor in the susceptibility for the development of chronic pancreatitis; transforming growth factor-beta1 (TGF-beta1) plays a central role in the pathogenesis of pancreatic fibrogenesis. The aim of our study was to analyse the relevance of TGF-beta1, interleukin-8 (IL-8) and tumor necrosis factor-alpha (TNF-alpha) polymorphisms in patients with chronic pancreatitis. PATIENTS: of the 83 patients enrolled in the study, 43 were treated medically and 40 patients underwent surgical intervention. Healthy blood donors (n=75) served as controls. METHODS: the polymorphisms of TGF-beta1 +869 T--> C and IL-8 -251 T-->A were determined by the ARMS method, while that of TNF-alpha -308 was investigated using NcoI RFLP. RESULTS: there was a higher frequency (50%) of the TT genotype of TGF-beta1 +869, with a concomitantly higher TGF-beta1 level in the plasma (5.2 +/- 1.7 ng/mL) of patients with chronic pancreatitis than in healthy blood donors (28% and 2.8 +/- 0.9 ng/mL respectively). The number of TT homozygotes differed significantly between the patients who underwent surgical intervention and the controls, and even between the surgical and the non-surgical patients. The frequency of the T/A genotype with higher IL-8 production, was significantly higher in both groups of patients than in the controls (58% and 58% versus 40%). No correlation was found between the TNF-alpha -308 polymorphism and chronic pancreatitis. CONCLUSIONS: correlations of the TGF-beta1 and IL-8 single nucleotide polymorphisms (SNPs) with chronic pancreatitis underline the importance of these cytokines in the pathomechanism of the disease. Moreover, it seems that the TT genotype of +869 TGF-beta1 might be a risk factor for the development of a severe form of chronic pancreatitis, and could serve as a prognostic sign for any future surgical intervention or even repeat surgery. Further studies on a larger group of patients, in addition to a follow-up study, are necessary to confirm this preliminary observation.

High mobility group box 1 protein induction by Mycobacterium bovis BCG.

UNLABELLED: High mobility group box 1 protein (HMGB1), a nuclear protein, is a critical cytokine that mediates the response to infection, injury, and inflammation. The aim of our study was to elaborate a reliable in vitro model to investigate whether Mycobacterium bovis BCG is able to induce HMGB1 secretion from the monocytic U-937 cells. Western blot technique was applied for the detection of HMGB1 from supernatants of cells, following induction with Mycobacterium bovis BCG. Densitometric analysis revealed higher concentrations of HMGB1 in cell supernatants stimulated with BCG than in the supernatants of the control, nonstimulated cells. Further quantitation of the secreted HMGB1 was performed by ELISA. The BCG strain resulted in a higher amount of secreted HMGB1 (450 +/- 44 ng/mL) than that of LPS (84 +/- 12 ng/mL) or Staphylococcus aureus (150 +/- 14 ng/mL). BCG and Phorbol -12-myristate -13 acetate (PMA), added together, resulted in the highest HMGB1 secretion (645 +/- 125 ng/mL). The translocation of the HMGB1 towards the cytoplasm following infection of cells with BCG was demonstrated by immunofluorescence examinations. CONCLUSION: Our pilot experiments draw attention to the HMGB1 inducing ability of Mycobacterium bovis. Assesment of the pathophysiological role of this late cytokine in mycobacterial infections demands further in vitro and in vivo examinations.

Association of beta-defensin 1 single nucleotide polymorphisms with Crohn's disease.

OBJECTIVE: It has been suggested that deficient defensin expression is associated with the chronic inflammation of Crohn's disease. The regional localization of Crohn's disease, ileal or colonic disease can be linked to different defensin profiles. As constitutive beta-defensin 1 has a colonic expression, we considered it of interest to investigate single nucleotide polymorphisms (SNPs) of the beta-defensin 1 gene (DEFB1) in Crohn's disease. MATERIAL AND METHODS: Three SNPs of the DEFB1 gene, DEFB1 G-20A (rs11362), DEFB1 C-44G (rs1800972) and DEFB1 G-52A (rs1799946), were genotyped either by Custom TaqMan SNP genotyping assays or by restriction fragment length polymorphisms (RFLP) in 190 patients with Crohn's disease and 95 Hungarian controls. RESULTS: It was found that the G-20A and C-44G SNPs had a strong association with the colonic and ileocolonic localizations of the disease, respectively, but no association was detected for the ileal localization. A significantly higher frequency of the GA genotype of G-20A was observed among patients with colonic localization (60%) as compared with healthy controls (39%), with an odds ratio (OR) of 2.39. The GG genotype of C-44G SNP, which is regarded as a protective genotype, was much less frequent (4%) among patients than among controls (12%), OR 3.367. CONCLUSIONS: These results indicate that genetic variations in the DEFB1 gene encoding constitutive human beta-defensin 1 may be associated with the risk for Crohn's disease and may determine disease phenotype, e.g. colonic localization.

Mycobacterium bovis BCG induces high mobility group box 1 protein release from monocytic cells.

UNLABELLED: High mobility group box 1 protein (HMGB-1), a nuclear protein is a critical cytokine that mediates the response to infection, injury and inflammation. The aim of our study was to elaborate a reliable in vitro model to investigate whether Mycobacterium bovis BCG is able to induce HMGB-1 secretion from the monocytic U-937 cells. Western blot technique was applied for the detection of HMGB-1 from supernatants of cells, following induction with LPS, Staphylococcus aureus, and Mycobacterium bovis BCG. HMGB-1 was subjected to MALDI-TOF mass and PSD analysis. Quantitation of the secreted HMGB-1 was performed by ELISA. The BCG strain induced higher amounts of secreted HMGB-1 than LPS or Staphylococcus aureus. The translocation of the HMGB-1 to the cytoplasm following infection of cells with BCG was demonstrated by immunofluorescence examinations. CONCLUSION: Our pilot experiments draw attention the to HMGB-1-inducing ability of Mycobacterium bovis. Assessment of the pathophysiological role of this late cytokine in mycobacterial infections demands further in vitro and in vivo examinations.

Genetic polymorphisms of NOD1 and IL-8, but not polymorphisms of TLR4 genes, are associated with Helicobacter pylori-induced duodenal ulcer and gastritis.

BACKGROUND: Intracellular pathogen receptor NOD1 is involved in the epithelial cell sensing Helicobacter pylori, which results in a considerable interleukin (IL)-8 production. The aim of this study was to evaluate the relationship between NOD1 and IL-8 genetic polymorphisms and the development of H. pylori-induced gastritis and duodenal ulcer (DU), as compared with TLR4 polymorphisms. MATERIALS AND METHODS: Eighty-five patients with DU and 135 patients with gastritis were enrolled in the study. Seventy-five serologically H. pylori-positive subjects without gastric or duodenal symptoms served as controls. The G796A (E266K) NOD1 polymorphism was determined by restriction fragment length polymorphism, and the -251 IL-8 polymorphism by amplification refractory mutation system method. The TLR4 (ASP/299/Gly and Thr/399/Ile) gene polymorphisms were examined by melting point analysis. RESULTS: AA homozygote mutant variants of NOD1 were detected in 20% of the H. pylori-positive patients with DU versus 7% of H. pylori-positive patients with gastritis and versus 6% of the H. pylori-positive healthy controls. The IL-8 heterozygote mutant variant was detected with a significantly higher frequency among the DU patients and those with gastritis than among the H. pylori-positive controls. However, no significant correlation concerning the frequency of the TLR4 gene polymorphism could be revealed between any group of patients and the controls. CONCLUSION: E266K CARD4/NOD1, but not the TLR4 gene polymorphism increases the risk of peptic ulceration in H. pylori-positive patients. The -251 IL-8 polymorphism was significantly associated with either gastritis or DU in H. pylori-infected subjects. Host factors including intracellular pathogen receptors and IL-8 production play an important role in H. pylori-induced gastric mucosal damage.