Abstract : BACKGROUND: Sepsis profoundly alters immune homeostasis. Cytokine release after whole blood lipopolysaccharide (LPS)-stimulation reflects cell function across multiple immune cell classes and represents the immune response to LPS. The main goal of this study was to evaluate the prognostic value of ex vivo stimulation of whole blood with LPS in sepsis.
METHODS: Blood was drawn on day 1 and day 7 after admission, and stimulated ex vivo with LPS. Tumour necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6 and IL-10 were measured with and without stimulation. Our primary outcome measure was the persistence of at least one organ dysfunction at day 7. Organ dysfunction was defined according to the SOFA components by a score ≥ 2.
RESULTS: Forty-nine patients with sepsis from a 21-bed intensive care unit, and 23 healthy volunteers were enrolled. The blood of septic patients was less responsive to ex vivo stimulation with LPS than that of healthy controls at day 1 and 7, as demonstrated by lower TNF-α, IL-1β, IL-6 and IL-10 release. Persistent organ dysfunction was more frequent in patients with lower IL-10 release at day 1 but such an association was not found for pro-inflammatory cytokines. A persistent low IL-10 release at day 7 was also associated with persistent organ dysfunction.
CONCLUSION: These data suggest that the capacity to produce IL-10 in response to whole blood ex vivo stimulation early in sepsis, as well as persistent low IL-10 response over time, may help in prognostication and patient stratification. These results will need to be confirmed in future studies.
