Circulating CD14+CD163+CD209+ M2-like monocytes are associated with the severity of infection in Helicobacter pylori-positive patients

Abstract

Helicobacter pylori (H. pylori) initiates a robust host immune response and subsequently results in chronic inflammation in the gastric mucosa. This study monitored the circulating monocyte subsets and measured the plasma levels of IL-10 and IL-12 in response to H. pylori infection in 35 H. pylori-associated gastritis patients and 14 healthy controls. We found that the numbers of CD14⁺CD163^-CD64⁺ M1-like monocytes as well as CD14⁺CD163⁺CD206⁺, CD14⁺CD163⁺CD209⁺, and CD14⁺CD163⁺IL-10⁺ M2-like monocytes were significantly increased in H. pylori-infected patients in comparison with the controls, accompanied by higher levels of plasma IL-10. In addition, IL-10 production was significantly higher in the stimulated M2-like cells from patients with H. pylori infection compared with controls. Moreover, the H. pylori-infected patients with CagA- or VacA-positive strains had a significantly higher number of CD14⁺CD163⁺CD206⁺, CD14⁺CD163⁺CD209⁺, CD14⁺CD163⁺IL-10⁺ monocytes compared to those with CagA- or VacA-negative strains. Furthermore, patients suffering from H. pylori-positive peptic ulcers had a greater number of CD14⁺CD163⁺CD209⁺ monocytes than H. pylori-positive nonatrophic or atrophic gastritis patients, with the numbers of CD14⁺CD163⁺CD209⁺ monocytes positively correlated with the extent of H. pylori infection. Notably, the triple anti-H. pylori therapy significantly reduced the numbers of CD14⁺CD163⁺CD206⁺ and CD14⁺CD163⁺CD209⁺ monocyte subsets. In conclusion, CD14⁺CD163⁺CD209⁺ M2-like monocyte subsets are increased in H. pylori infection, especially in patients with peptic ulcers. CD14⁺CD163⁺CD209⁺ M2-like monocytes are positively associated with the severity of H. pylori infection.

Keywords: Gastritis; Helicobacter pylori infection; IL-10; Monocytes.