OBJECTIVESTo study the effect of monoclonal antibody (McAb) against helicobacter pylori (Hp) ureB, 1F11 on platelet aggregation and activation, and its mechanism.

METHODSThe relativity between human platelet glycoproteins (GPs) and Hp ureB was identified by Western blot and FCM. Platelet aggregation was measured by turbidimetry, and P-selectin and TXB2 assay by ELISA.

RESULTS1F11 could bind to platelet GPIIIa, and ADP-induced platelet aggregation was inhibited by 1F11 in a dose-dependent manner. However, 1F11 had no effect on plasma P-selectin and TXB2 induced by ADP. The FCM results show that the positive rates of platelet binding to FITC-SZ21 was decreased from 99.5% to 77.4% after addition of 1F11.

CONCLUSIONMcAb against Hp ureB 1F11 inhibits platelet aggregation through binding to platelet GPIIIa but does not block platelet activation. There might be crossed-epitopes on Hp ureB and platelet GPIIIa, and Hp infection might be involved in ITP immunopathology.

Antibodies, Bacterial ; pharmacology ; Antibodies, Monoclonal ; pharmacology ; Bacterial Proteins ; immunology ; metabolism ; Helicobacter pylori ; immunology ; Humans ; Integrin beta3 ; immunology ; P-Selectin ; immunology ; Platelet Activation ; drug effects ; Platelet Aggregation ; drug effects ; Urease ; immunology ; Urokinase-Type Plasminogen Activator ; immunology

OBJECTIVETo evaluate the effect of Helicobacter pylor (Hp) eradication in children with acute idiopathic thrombocytopenic purpura (ITP).

METHODSNinety-three children with acute ITP and Hp infection were divided into two groups and treated with prednisone and Hp eradication (group A, 51 cases) or with prednisone without Hp eradication (group B, 42 cases).

RESULTSThe Hp eradication rate was 94.1% in group A. No difference was found in the therapeutic effects on IPT between the two groups, but the recurrence rate in one year in group A was significantly lower than that in group B.

CONCLUSIONNHp eradication does not obviously enhance the therapeutic effect on childhood acute ITP, but can decrease the relapse rate in one year. HP eradication therapy is recommended in children with acute ITP and Hp infection.

Adolescent ; Anti-Bacterial Agents ; therapeutic use ; Child ; Child, Preschool ; Drug Therapy, Combination ; Female ; Helicobacter Infections ; drug therapy ; Helicobacter pylori ; drug effects ; immunology ; Humans ; Male ; Prednisone ; therapeutic use ; Purpura, Thrombocytopenic, Idiopathic ; immunology ; microbiology

Helicobacter pylori (H. pylori) induces the activation of nuclear factor-kB (NF-kappaB) and cytokine expression in gastric epithelial cells. The Janus kinase/signal transducers and activators of transcription (Jak/Stat) cascade is the inflammatory signaling in various cells. The purpose of the present study is to determine whether H. pylori-induced activation of NF-kappaB and the expression of interleukin-8 (IL-8) are mediated by the activation of Jak1/Stat3 in gastric epithelial (AGS) cells. Thus, gastric epithelial AGS cells were infected with H. pylori in Korean isolates (HP99) at bacterium/cell ratio of 300:1, and the level of IL-8 in the medium was determined by enzyme-linked immonosorbent assay. Phospho-specific and total forms of Jak1/Stat3 and IkappaBalpha were assessed by Western blot analysis, and NF-kappaB activation was determined by electrophoretic mobility shift assay. The results showed that H. pylori induced the activation of Jak1/Stat3 and IL-8 production, which was inhibited by a Jak/Stat3 specific inhibitor AG490 in AGS cells in a dose-dependent manner. H. pylori-induced activation of NF-kappaB, determined by phosphorylation of IkappaBalpha and NF-kappaB-DNA binding activity, were inhibited by AG490. In conclusion, Jak1/Stat3 activation may mediate the activation of NF-kappaB and the expression of IL-8 in H. pylori-infected AGS cells. Inhibition of Jak1/Stat3 may be beneficial for the treatment of H. pylori-induced gastric inflammation, since the activation of NF-kappaB is inhibited and inflammatory cytokine expression is suppressed.
Blotting, Western ; DNA, Bacterial/analysis/genetics ; Epithelial Cells/metabolism ; Gastric Mucosa/drug effects/*immunology/microbiology ; Gene Expression Regulation/drug effects/*immunology ; Gene Expression Regulation, Bacterial ; Helicobacter Infections/immunology/*metabolism ; Helicobacter pylori/genetics/pathogenicity/*physiology ; Humans ; Interleukin-8/genetics/*metabolism ; Janus Kinase 1 ; NF-kappa B/biosynthesis/*metabolism ; Phosphorylation ; RNA, Messenger/metabolism ; STAT3 Transcription Factor ; Signal Transduction/genetics

Helicobacter pylori (H. pylori) induces the activation of nuclear factor-kB (NF-kappaB) and cytokine expression in gastric epithelial cells. The Janus kinase/signal transducers and activators of transcription (Jak/Stat) cascade is the inflammatory signaling in various cells. The purpose of the present study is to determine whether H. pylori-induced activation of NF-kappaB and the expression of interleukin-8 (IL-8) are mediated by the activation of Jak1/Stat3 in gastric epithelial (AGS) cells. Thus, gastric epithelial AGS cells were infected with H. pylori in Korean isolates (HP99) at bacterium/cell ratio of 300:1, and the level of IL-8 in the medium was determined by enzyme-linked immonosorbent assay. Phospho-specific and total forms of Jak1/Stat3 and IkappaBalpha were assessed by Western blot analysis, and NF-kappaB activation was determined by electrophoretic mobility shift assay. The results showed that H. pylori induced the activation of Jak1/Stat3 and IL-8 production, which was inhibited by a Jak/Stat3 specific inhibitor AG490 in AGS cells in a dose-dependent manner. H. pylori-induced activation of NF-kappaB, determined by phosphorylation of IkappaBalpha and NF-kappaB-DNA binding activity, were inhibited by AG490. In conclusion, Jak1/Stat3 activation may mediate the activation of NF-kappaB and the expression of IL-8 in H. pylori-infected AGS cells. Inhibition of Jak1/Stat3 may be beneficial for the treatment of H. pylori-induced gastric inflammation, since the activation of NF-kappaB is inhibited and inflammatory cytokine expression is suppressed.
Blotting, Western ; DNA, Bacterial/analysis/genetics ; Epithelial Cells/metabolism ; Gastric Mucosa/drug effects/*immunology/microbiology ; Gene Expression Regulation/drug effects/*immunology ; Gene Expression Regulation, Bacterial ; Helicobacter Infections/immunology/*metabolism ; Helicobacter pylori/genetics/pathogenicity/*physiology ; Humans ; Interleukin-8/genetics/*metabolism ; Janus Kinase 1 ; NF-kappa B/biosynthesis/*metabolism ; Phosphorylation ; RNA, Messenger/metabolism ; STAT3 Transcription Factor ; Signal Transduction/genetics

Korea and Japan show the highest incidence of gastric cancer and Helicobacter pylori infection. New 2013 guidelines on H. pylori infection differ between the two countries with regard to the indications for H. pylori eradication, diagnostic methods, and treatment regimens. Indications for eradication in Korean guideline focus on specific diseases such as peptic ulcer disease, low-grade gastric mucosa-associated lymphoid tissue lymphoma, and after resection of early gastric cancer, while Japanese guideline includes all H. pylori-associated gastritis for the prevention of dissemination. With regard to the diagnosis, either noninvasive or invasive method (except for bacterial culture) is recommended in Korea, while two noninvasive tests including serum anti-H. pylori IgG antibody level are preferred in Japan. As for the treatment regimens, second-line treatment (quadruple bismuth-containing regimen) is recommended without first-line triple therapy in areas of high clarithromycin resistance in Korea. However, there is no bismuth-based second-line treatment in Japan, and the Japanese regimen consists of a lower dose of antibiotics for a shorter duration (7 days). Such discrepancies between the two countries are based not only on the differences in the literature search and interpretation, but also on the different approvals granted by the national health insurance system, manufacturing process of the antibiotics, and diagnostic techniques in each country. Collaborations are required to minimize the discrepancies between the two countries based on cost-effectiveness.
Anti-Bacterial Agents/pharmacology/*therapeutic use ; Antibodies/blood ; Bismuth/pharmacology/therapeutic use ; Disease Eradication/trends ; Drug Administration Schedule ; Guidelines as Topic ; Helicobacter Infections/complications/diagnosis/*drug therapy ; *Helicobacter pylori/drug effects/immunology ; Humans ; Japan ; Lymphoma, B-Cell, Marginal Zone/complications/surgery ; Republic of Korea ; Stomach Neoplasms/complications/surgery

The epithelial cytokine response, associated with reactive oxygen species (ROS), is important in Helicobacter pylori (H. pylori)-induced inflammation. H. pylori induces the production of ROS, which may be involved in the activation of mitogen-activated protein kinases (MAPK), janus kinase/signal transducers and activators of transcription (Jak/Stat), and oxidant-sensitive transcription factor, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kappaB), and thus, expression of interleukin-8 (IL-8) in gastric epithelial cells. alpha-lipoic acid, a naturally occurring thiol compound, is a potential antioxidant. It shows beneficial effects in treatment of oxidant-associated diseases including diabetes. The present study is purposed to investigate whether alpha-lipoic acid inhibits expression of inflammatory cytokine IL-8 by suppressing activation of MAPK, Jak/Stat, and NF-kappaB in H. pylori-infected gastric epithelial cells. Gastric epithelial AGS cells were pretreated with or without alpha-lipoic acid for 2 h and infected with H. pylori in a Korean isolate (HP99) at a ratio of 300:1. IL-8 mRNA expression was analyzed by RT-PCR analysis. IL-8 levels in the medium were determined by enzyme-linked immunosorbent assay. NF-kappaB-DNA binding activity was determined by electrophoretic mobility shift assay. Phospho-specific and total forms of MAPK and Jak/Stat were assessed by Western blot analysis. ROS levels were determined using dichlorofluorescein fluorescence. As a result, H. pylori induced increases in ROS levels, mRNA, and protein levels of IL-8, as well as the activation of MAPK [extracellular signal-regulated kinase 1/2 (ERK1/2), c-Jun NH2-terminal kinase 1/2 (JNK1/2), p38], Jak/Stat (Jak1/2, Stat3), and NF-kappaB in AGS cells, which was inhibited by alpha-lipoic acid. In conclusion, alpha-lipoic acid may be beneficial for prevention and/or treatment of H. pylori infection-associated gastric inflammation.
Enzyme-Linked Immunosorbent Assay ; Epithelial Cells/metabolism ; Gastric Mucosa/*drug effects/metabolism/microbiology ; Gene Expression Regulation, Bacterial ; Helicobacter Infections/immunology/*metabolism ; Helicobacter pylori/drug effects/*pathogenicity ; Humans ; Interleukin-8/genetics/*metabolism ; JNK Mitogen-Activated Protein Kinases ; Janus Kinase 1 ; Mitogen-Activated Protein Kinases/*biosynthesis ; NF-kappa B/*metabolism ; RNA, Messenger/isolation & purification/metabolism ; Reactive Oxygen Species/metabolism ; STAT3 Transcription Factor ; Stomach/metabolism/*microbiology ; Thioctic Acid/*pharmacology