Background: The neutrophil-activating protein (HP-NAP) of Helicobacter pylori is a protective antigen and a major virulence factor of this bacteria. Stimulating the immune system for helicobacter infection treatment could have an important role. The aim of study is to assess the effect of recombinant Neutrophil activating protein (Hp-NapA) of helicobacter pylori on proliferation and viability of peritoneal macrophages from BALB/c mice.

Materials and Methods: In this experimental study, recombinant Hp-NapA of helicobacter pylori was produced in vitro. Mice peritoneal macrophages were purified and cultured. Different concentrations of recombinant Hp-NapA was used for macrophages stimulation. MTT assay was performed to assess the viability and proliferation of macrophages.

Results: The results elucidated that the increasing effect of stimulation with recombinant Hp-NapA was significant at the dose of 30 µg/ml  (p=0.01). The rate of viabitity was significantly higher than control group at the doses of 30 and 60 µg/ml and in the concurrency series of recombinant protein with lipopolysaccharid, there was a statistically significarit increase in proliferation at just these doses.

Conclusion: According to our findings, recombinant Hp-NapA has a positive effect on proliferation, viability and function of peritoneal macrophages. Therefore, it is proposed that recombinant Hp-NapA can be studied as an immunomodulator for immunotherapy.