Immune function testing in sepsis patients receiving sodium selenite

We examined in a longitudinal study the role of sodium selenite in sepsis patients in strengthening the immune performance in whole blood samples using immune functional assays.

This was a sub-study from a randomized, double blinded multicenter clinical trial (SISPCT) registered with www.clinicaltrials.gov (NCT00832039) and with data collected at our center. Full blood samples were incubated with various recall antigens and the supernatants were measured for their cytokine concentrations as markers for immune response. Data from days 0, 4, 7, 14, and 21 (from sepsis onset) were analyzed using a generalized least squares model in R to appropriately take the longitudinal structure and the missing values into account.

From the 76 patients enrolled in the study at our center, 40 were randomized to selenium therapy and 36 to placebo. The analyses of immune response assay data showed no statistical difference between the selenium and placebo groups at each of the time points. There was however an overall dampening of cytokine release, which tended to recover over time in both groups.

Selenium has long been an adjuvant therapy in treating sepsis. Recently, it was proven to not have beneficial effects on the mortality outcome. Using data from our center in this sub-cohort study, we identified no relative improvement in cytokine release of stimulated blood immune cells ex vivo from patients with selenium therapy over a three-week period. This offers a potential explanation for the lack of beneficial effects of selenium in sepsis patients.