Sulfotransferase homolog 2 receptors blockade on monocyte subsets along with their inflammatory cytokines for septic lung injury.

PURPOSE OF THE STUDY

To observe the dynamic changes in monocyte subsets during septic lung injury and to assess the anti-inflammatory role of the sulfotransferase homolog 2 (ST2) receptor.

MATERIALS AND METHODS

Dynamic changes of monocyte subsets from patients with septic lung injury and mice post-cecal ligation and puncture (CLP) were monitored. ST2 receptors on mice monocytes and concentrations of IL-33, IL-1β, IL-12, and IL-27 from peripheral blood or culture supernatant were detected.

RESULTS

CD14CD16 (Mo0) and CD14CD16 (Mo2) monocyte subsets were significantly expanded in patients with sepsis-related acute respiratory distress syndrome. In sepsis model mice, monocyte counts, particularly of Ly6C and CDLy6C monocytes, were significantly increased. The mean optical density value of TNF-α after CLP mainly increased after 24 h, whereas that of IL-6 was significantly increased at all time points assessed after CLP. The levels of IL-1β, IL-12, IL-27, and IL-33 increased to variable degrees at 6, 12, 24, and 48h after CLP, and ST2 monocytes were significantly expanded in sepsis model mice compared to sham-operated mice. ST2 receptor blockade suppressed IL-1β and IL-12 production in cell culture.

CONCLUSIONS

Changes in monocyte subsets expressing the ST2 receptor play an important role in septic lung injury by modulating inflammatory cytokine secretion.