Overproduction of the pro-inflammatory cytokines by peripheral blood mononuclear cells from Helicobacter pylori-infected patients with peptic ulcer

Introduction and Objectives: H. pylori is one of the most prevalent infection in human and chronic infection with this bacterium may lead to peptic ulcer (PU), gastric mucosa-associated lymphoid tissue (MALT) lymphomas and gastric cancer. The host immunologic and genetic parameters play a critical role in the expression of the bacteria-related clinical symptoms. This investigation aimed to evaluate the expression pro-inflammatory cytokines IFN-γ and IL-12 by peripheral blood mononuclear cells (PBMCs) from H. pylori-infected peptic ulcer (PU) patients and asymptomatic (AS) subjects. Material and Methods: The fresh PBMCs were obtained from 20 PU patients, 20 AS subjects and 20 non-infected individuals and were cultured for 32 hours without stimulation, in the presence H. pylori-derived crude extract or PHA. Then levels of the IFN-γ and IL-12 in the supernatants were measured using ELISA method. Results: No significant differences were observed between HP-stimulated PBMCs and non-stimulated PBMCs from non-infected individuals concerning the IFN-γ and IL-12 production. In both PU and AS groups, the levels of IFN-γ and IL-12 production by HP-stimulated PBMCs were significantly higher than non-stimulated PBMCs. The IFN-γ and IL-12 similarly expressed in non-stimulated PBMCs and PHA-stimulated PBMCs from PU patients, AS subjects and non-infected individuals. The amounts of IFN-γ and IL-12 production by HP-stimulated PBMCs from PU were significantly higher than equal cultures in AS subjects and non-infected individuals. Conclusion: The HP-stimulated PBMCs from PU produce higher amounts of IFN-γ and IL-12 than AS subjects and non-infected individuals that represent the possible contribution of these cytokine in the pathogenesis of PU.

Keywords:

H. pylori , Peptic ulcer , IFN-γ , IL-12