To investigate the expression of interleukin-35 (IL-35) in patients with sepsis and multiple organ dysfunction syndrome (MODS), and to explore its effect on disease prognosis.

A prospective study was conducted. Twenty-two patients with sepsis and MODS were selected as study group, and 20 healthy volunteers were selected as controls. Blood samples of the patients and the volunteers were taken within 1 hour of the patient's visit, and cytokines, such as IL-35, IL-4, IL-10, IL-17, INF-γ, and TGF-β, were simultaneously detected by enzyme-linked immunosorbent assay (ELISA). The expression level of CD4⁺CD25⁺FOXP3⁺ T_reg cells was detected by flow cytometry, and the acute physiology and chronic health status scoring systemⅡ (APACHE Ⅱ) was calculated. According to the survival outcome at 28 days after admission, the expression levels of IL-35 in the survival group (12 cases) and the death group (8 cases) were compared. The Spearman method was used to analyze the correlation between IL-35 level and the above indicators in patients with sepsis and MODS.

Compared with the control group, the IL-35 levels were significantly increased in the study group (P<0.05), and the IL-35 levels began to increase gradually on the first day of the disease, and significantly higher on the 7th day (P<0.01). The number of CD4⁺CD25⁺FOXP3⁺regulatory T cells increased in the study group, especially on the 4th day (P<0.01), and on the first day of the disease, the IL-35 levels were positively correlated to the number of CD4⁺CD25⁺FOXP3⁺T_reg cells (r=0.60, P<0.05). Compared with the control group, the levels of IL-10, IL-4, IL-17, INF-γ and TGF-β in the study group increased gradually with the course of disease, and were significantly higher on the 7th day than those on the 1st day and the 4th day (P<0.05). The IL-35 levels in the study group were positively correlated with INF-γ and TGF-β cytokines (P<0.05), whereas there was no significant relationship between the levels of IL-10, IL-4, and IL-17 (P>0.05). The IL-35 level in the death group was significantly lower than that in the survival group (P<0.05). IL-35 levels in the survival and death groups were analyzed by ROC curve with a AUC of 0.78 (P=0.03). The IL-35 level was negatively correlated with the APACHE-Ⅱ score in the study group (r=-0.78, P<0.01).

The IL-35 levels in patients with sepsis and MODS is significantly higher than that in healthy controls, and negatively correlated with APACHE Ⅱ score. The level of IL-35 has an important implication for the prognosis for patients with sepsis.

Interleukin-35; Cytokine; Sepsis; Multiple Organ Dysfunction Syndrome; Immune