Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:6.3.4.6 (urease)
 7,490 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Helicobacter pylori (Hp) infection almost invariably results in chronic antral gastritis, but only a proportion of patients develop peptic ulcer. Some Hp strains may be more ulcerogenic than others, but some ulcerogenic mechanisms may also depend on the type of the host immune response. In this study, the antigen specificity and the cytokine profile of 53 Hp-specific CD4+ T cell clones derived from the antral mucosa of five patients with Hp-induced uncomplicated chronic gastritis (CG) were assessed and compared with those of 34 Hp-specific CD4+ T cell clones derived from six Hp-infected patients with chronic gastritis and peptic ulcer (CG-PU). The majority (28/34; 82%) of gastric Hp-specific T cell clones from CG-PU patients expressed the Th1 profile and 17 (all Th1) of the 34 clones were specific for cytotoxin-associated protein (CagA). In contrast, 34 (64%) of the 53 Hp-specific gastric T cell clones derived from CG patients were able to secrete both Th1 and Th2 cytokines (Th0 profile) and only 36% expressed a polarized Th1 profile. The majority (85%) of Hp-specific clones from CG patients recognized Hp antigens other than CagA, since 13/53 (25%) were specific for urease, 6 (11%) for VacA, 6 (11%) for HSP and 20 (38%) for other undefined Hp antigens. Results provide evidence that the type of T helper cell response against Hp may vary according to the antigen involved and suggest that a polarized Th1 response may play a role in the genesis of peptic ulcer, whereas a local Th0 response, including interleukin-4 production, may represent an individual host factor which contributes to lower the degree of gastric inflammation and prevent ulcer complication.
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PMID:Different cytokine profile and antigen-specificity repertoire in Helicobacter pylori-specific T cell clones from the antrum of chronic gastritis patients with or without peptic ulcer. 924 87

Helicobacter pylori proteins CagA (cytotoxin-associated gene A) and VacA (vacuolating cytotoxin A) are among the virulence factors of this species. CagA gene carrying H. pylori strains are particularly associated with gastric adenocarsinoma. This study was conducted to evaluate Western Blot (WB) method to determine specific H. pylori antibodies in a group of patients with gastric cancer and in a control group with no malignancy. A total of 99 patients with gastric cancer (94 adenocarcinoma, 2 adenosquamous cell carcinoma, 3 non-Hodgkin lymphoma) and 150 control cases with epigastric complaints such as nausea, vomiting, diarrhea, gastroesophageal reflux and abdominal pain, were included to the study. H. pylori IgG-ELISA was positive in all study (mean age: 56.7 +/- 1.2 years, 62 male) and control (mean age: 24.2 +/- 1.3 years, 64 male) patients. Specific antibodies against CagA, VacA, OMP (outer membrane protein)-67, urease-A, urease-B, HSP (heat shock protein) and flagellin antigens determined by a commercial WB-based kit (RIDA Blot Helicobacter, R-Biopharm GmbH, Germany). Interestingly, no anti-VacA positivity was detected in none of the patient and control groups. The positivity rates for H. pylori CagA, OMP-67, urease A, urease-B, flagellin and HSP specific antibodies were as 78%, 54%, 37%, 60%, 53% and 82% in the gastric cancer group and 85%, 71%, 55%, 43%, 61% and 75% in the control group, respectively. There was no statistically significant difference (p > 0.05) between gastric carcinoma and control groups in terms of CagA, HSP and flagellin antibodies (p > 0.05). On the other hand, a statistically significant difference was found between the 2 groups in terms of urease-A, urease-B and OMP-67 (p < 0.01). These results suggested that this test should be assessed again by the manufacturer for its detection power directed towards specific H. pylori antibodies, especially for Vac-A. Further molecular and clinical studies are necessary to determine the factors that affect H. pylori virulence and disease prognosis.
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PMID:[Evaluation of Western Blot method for the detection of antibodies to Helicobacter pylori antigens in patients with gastric carcinoma and cases with epigastric complaints]. 2045 95