Postoperative PMBC-derived IL-6 and TNF-alpha-release is uninfluenced by IL-12-mediated restoration of IFN-gamma synthesis.

Objectives: Interferon gamma (IFN-gamma) synthesis in peripheral blood mononuclear cells (PBMCs) is suppressed after major surgical trauma. Interleukin-12 (IL-12) has been shown to stimulate IFN-gamma-synthesis. We hypothesised that exogenous IL-12 can increase perioperative pro-inflammatory cytokine release.

Is interferon gamma suppression after cardiac surgery caused by a decreased interleukin-12 synthesis?

Background: The suppression of interferon gamma (IFN-gamma) synthesis after cardiac surgery is discussed as a cause of postoperative immunosuppression that predisposes to postoperative infectious complications. Because several studies have suggested that interleukin-12 (IL-12) production by monocytes and macrophages is reduced after cardiac surgery, this might cause a decrease in IFN-gamma release. To better understand these processes, we assessed the role of IL-12 in IFN-gamma synthesis in vitro before and after cardiac surgery.

Hyporesponsiveness of T cell subsets after cardiac surgery: a product of altered cell function or merely a result of absolute cell count changes in peripheral blood?

Objective: The activity of the specific immune system and especially the function of T helper (TH) cells are reduced after cardiac surgery. This decrease is followed by an increase in TH2 cell activity and a delayed recovery of TH1 cell function (TH1/TH2 shift). Neither the underlying cause nor the relationship between the absolute numbers of T lymphocyte subpopulations, the state of activation of these cells and cytokine synthesis in cell culture has been clarified.

Pro-inflammatory cytokines after different kinds of cardio-thoracic surgical procedures: is what we see what we know?

Objective: Due to the combination of local trauma, extracorporeal circulation (ECC), and pulmonary and myocardial reperfusion, cardiac surgery leads to substantial changes in the immune system and possibly to post-operative complications. Procedures without ECC, however, have failed to demonstrate clear advantages. We hypothesized that ECC is far less important in this context than the reperfusion/reventilation of the lung parenchyma and the surgical trauma.