title: Effects of cytotoxin-associated gene A (CagA) positive Helicobacter pylori infection on anti-platelet glycoprotein antibody producing B cells in patients with primary idiopathic thrombocytopenic purpura (ITP).
abstract: OBJECTIVE
  To explore the effects of cytotoxin-associated gene A (CagA) positive Helicobacter pylori (H. pylori or HP) infection on circulating B cells producing specific platelet glycoprotein antibodies and the association between therapeutic outcomes in primary idiopathic thrombocytopenic purpura (ITP) patients.
  
  
  METHODS
  A total of 76 newly diagnosed primary ITP patients were included in the study which was conducted at the first affiliated hospital of Shantou University Medical college, in Shantou city China, between January 2013 and January 2014. These patients were tested for H. pylori infection by (13)C urea breath test and for anti-CagA antibody in H. pylori positive cases by enzyme-linked immunosorbent assay (ELISA) method. Anti-GPIb and anti-GPIIb/IIIa antibody-producing B cells were measured using an enzyme-linked immunospot (ELISPOT) assay in all ITP patients and 30 controls. Anti-nuclear antibody (ANA) was also detected in ITP patients.
  
  
  RESULTS
  The numbers of anti-GPIIb/IIIa antibody-producing B cells in HP+CagA+ patients were higher than in HP+CagA- or HP- patients. However, anti-GPIb antibody-producing B cells were found higher in HP- patients. Analysis of treatment outcomes showed that a therapeutic response was more likely in patients presenting anti-GPIIb/IIIa B cells, but the poor response was found to be associated with anti-GPIb B cells and ANA presences.
  
  
  CONCLUSIONS
  CagA antigen of H. pylori may induce anti-GPIIb/IIIa antibodies production by a molecular mimicry mechanism. Anti-GPIIb/IIIa and anti-GPIb antibody producing B Cells detection is useful for predicting treatment effects of primary ITP.
authors: Yuan-Shan Cheng, MD, Department of Hematology, The First Affiliated Hospital of Shantou University Medical College, Guangdong, China, 515000.
authors: Yuan-Shan
authors: YS
authors: Cheng
authors: Li-Ping Kuang, MD, Department of Pathology, Shantou Central Hospital, Guangdong, China, 515000.
authors: Li-Ping
authors: LP
authors: Kuang
authors: Chun-Lan Zhuang, MD, Department of Hematology, The First Affiliated Hospital of Shantou University Medical College, Guangdong, China, 515000.
authors: Chun-Lan
authors: CL
authors: Zhuang
authors: Jia-Dian Jiang, MD, Department of Hematology, The First Affiliated Hospital of Shantou University Medical College, Guangdong, China, 515000.
authors: Jia-Dian
authors: JD
authors: Jiang
authors: Man Shi, MD, Department of Hematology, The First Affiliated Hospital of Shantou University Medical College, Guangdong, China, 515000.
authors: Man
authors: M
authors: Shi
keywords: Anti-glycoprotein antibody; Cytotoxin-associated gene A; Helicobacter pylori; Idiopathic thrombocytopenic purpura