Immunosuppressive effects of apoptotic cells

Apoptotic cell death is important in the development and homeostasis of multicellular organisms1 and is a highly controlled means of eliminating dangerous, damaged or unnecessary cells without causing an inflammatory response or tissue damage1,2. We now show that the presence of apoptotic cells during monocyte activation increases their secretion of the anti-inflammatory and immunoregulatory cytokine interleukin 10 (IL-10) and decreases secretion of the proinflammatory cytokines tumour necrosis factor-α (TNF-α), IL-1 and IL-12. This may inhibit inflammation and contribute to impaired cell-mediated immunity in conditions associated with increased apoptosis, such as viral infections, pregnancy, cancer and exposure to radiation.