Dysregulation of in vitro cytokine production by monocytes during sepsis

Abstract

The production by monocytes of interleukin-1α (IL-1α), interleukin-β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNFα) in intensive care unit (ICU) patients with sepsis syndrome (n = 23) or noninfectious shock (n = 6) is reported. Plasma cytokines, cell-associated cytokines within freshly isolated monocytes and LPS-induced in vitro cytokine production were assessed at admission and at regular intervals during ICU stay. TNFα and IL-6 were the most frequently detected circulating cytokines. Despite the fact that IL-1α is the main cytokine found within monocytes upon in vitro activation of cells from healthy individuals, it was very rarely detected within freshly isolated monocytes from septic patients, and levels of cell-associated IL-1β were lower than those of TNFα. Cell-associated IL-1β and TNFα were not correlated with corresponding levels in plasma. Upon LPS stimulation, we observed a profound decrease of in vitro IL-1α production by monocytes in all patients, an