[Cytokine production in surgical stress]

Surgical injury influences the function of mononuclear cells, leading to various systemic responses. Proinflammatory cytokines such as tumor necrosis factor alpha (TNF alpha), interleukin (IL)-1, -6, -8, and the antiinflammatory cytokine IL-10, which are mainly produced by mononuclear cells, are known to play an important role in the response to and pathogenesis of surgical stress. TNF alpha production by monocytes is extremely upregulated, but monocyte HLA-DR antigen expression is suppressed in patients with surgical stress. While production of Th1 cytokines such as IL-12 and interferon-gamma by mononuclear cells is suppressed, production of Th2 cytokines and IL-10 is upregulated during surgical stress. Immune suppression following surgical stress has been clarified recently in terms of Th1 and Th2 cytokine production balance mainly caused by mononuclear cells. It is thought to be very important to maintain immunological function after surgical stress by controlling cytokine production and balance.