Glucocorticoids regulate the proliferation of T cells via miRNA-155 in septic shock.

Although previous studies have evaluated the roles of glucocorticoids and lymphocytes in septic shock, the precise mechanism remains unclear. The present study focused on investigating the influence of glucocorticoids on micro (mi)RNA-155 expression levels and the proliferation of T lymphocytes in septic shock. T cells were harvested from in the peripheral blood of patients with septic shock and healthy volunteers and were cultured in vitro. miRNA-155 levels and cell proliferation rates were subsequently analyzed. The proliferation of T cells from patients with septic shock was observed to be significantly lower as compared with that of T cells from healthy volunteers (P<0.05). Furthermore, miRNA-155 levels were significantly higher in the T cells from patients with septic shock, as compared with those from healthy volunteers (P<0.05). Notably, stimulation with dexamethasone increased the proliferation of T lymphocytes from patients with septic shock in a concentration-dependent manner, and markedly reduced miRNA-155 levels. Furthermore, transfection with an anti-miRNA-155 oligodoxynucleotide significantly increased the proliferation of T lymphocytes from patients with septic shock. In conclusion, the results of the present study indicate that glucocorticoids may regulate T-lymphocyte proliferation via the miRNA-155 pathway during septic shock. Therefore, miRNA-155 may be a potential therapeutic target in the treatment of septic shock.