[The role of IL-10 in patients with SIRS (systemic inflammatory response syndrome)--in relation to TNF activity]

The role of IL-10 (Interleukin 10) in the patients with SIRS was demonstrated in relation to the TNF (Tumor Necrosis Factor). 1. Clinical observations Thirty three materials of IL-10 and 43 materials of TNF were taken from a total of 46 patients with SIRS. And their concentration of serum were compared with those of healthy volunteers (TNF: n = 12, IL-10: n = 9). The value of IL-10 and TNF in SIRS patients was significantly higher than those of healthy volunteers (p > 0.05 in IL-10, p < 0.01 in TNF). Also, the values of both IL-10 and TNF in the patients with MOF (n = 22) were higher than those of the patients without MOF (n = 24) (p < 0.05 in IL-10, p < 0.01 in TNF). Both the serum values of IL-10 and TNF in 7 patients with SIRS, whose materials were obtained at two points of their clinical course, were decreased in accordance with the favorable prognosis. In these patients, the changes in IL-10 and TNF were observed in parallel. 2. Experimental observations Five 4 week ICR mice were used in an experimental study. The serum concentration of TNF and IL-10 increased to the maximum at 2 hours after 4 mg/kg of LPS injection. TNF level disappeared at 6 hours, but IL-10 level still remained at this point. Both the serum and BALF levels of TNF increased by LPS injection which was inhibited by the intraabdominal pretreatment of 200 micrograms of IL-10 (in serum: p < 0.1, in BALF: p < 0.05). By preincubation of mice alveolar macrophages with IL-10, TNF production from the macrophage resulting from LPS loading also was significantly inhibited (p < 0.01). 3. From the above, it may be concluded that IL-10 inhibits TNF secretion from monocyte and protects against the pathogenic activity of TNF in the SIRS patient.