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.

Exogenous IL-12 and its effect on TH1/TH2 cell activity after cardiac surgery.

There is controversy about the origin of the alterations in T helper 1 (TH1)/TH2 cell activity after major surgical procedures such as on-pump cardiac surgery. We hypothesized that a postoperative decrease in interferon (IFN) gamma-producing TH1 lymphocyte activity may be the sole cause of this TH1/TH2 shift and that the addition of recombinant IL-12 can reverse TH1 suppression. Peripheral blood mononuclear cell fractions from 20 low-risk elective cardiac surgery patients were analyzed preoperatively (d0) and on the first (d1), third (d3), and sixth (d6) postoperative days.

A comparison of monocyte counts and ex vivo and in vitro monocyte cytokine production after major surgical trauma.

Background: Impaired function of cluster of differentiation 14-positive (CD14+) monocytes (MOs) after major surgical trauma is believed to predispose to infectious complications. Postoperative decreases in human leukocyte antigen (HLA)-DR expression, tumor necrosis factor-alpha (TNF-alpha) production and interleukin (IL)-12 synthesis have been reported. There are no studies comparing absolute MO counts and MO cytokine synthesis in peripheral blood and stimulated cultures.

Procalcitonin levels after different types of conventional thoracic surgery.

Background: Procalcitonin (PCT) is currently discussed as an indicator of postoperative complications following thoracic surgery. Serum levels of PCT are different after thoracoscopic and conventional surgical approaches. We conducted this study to test the hypothesis that different types of conventional thoracic surgery are associated with different postoperative serum levels of acute-phase proteins or pro-inflammatory mediators.

Delayed recovery of human leukocyte antigen-DR expression after cardiac surgery with early non-lethal postoperative complications: only an epiphenomenon?

HLA-DR expression on peripheral blood monocytes is reduced after cardiac surgery. Little is known about the reconstitution of HLA-DR expression on peripheral blood monocytes in patients suffering from early non-fatal perioperative complications. We conducted a prospective study to prove whether these complications adversely affect the recovery of HLA-DR expression.

In vitro restoration of post-operatively decreased IFN-gamma levels after cardiac surgery and its effect on pro- and anti-inflammatory mediators.

Background: A decreased synthesis of interferon gamma (IFN-gamma) by TH 1 lymphocytes after cardiac operations with cardiopulmonary bypass (CPB) is part of the inflammatory response to local operative and systemic traumas. The consequences of this mechanism on the release of pro- and anti-inflammatory cytokines remain unclear. To evaluate the role of IFN-gamma, we added recombinant IFN-gamma to peripheral blood mononuclear cells (PBMCs) on the first post-operative day in an attempt to restore pre-operative values and then measured the release of pro- and anti-inflammatory cytokines in vitro.

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.

Immunoglobulin levels and lymphocyte subsets following cardiac operations: further evidence for a T-helper cell shifting.

Background: Recent data indicate that cardiac surgery with cardiopulmonary bypass (CPB) results in an imbalance of T-helper cell subsets towards the anti-inflammatory pathway mediating humoral immune response. However, little is known about immunoglobulin levels as an important part of humoral immune response after CPB. Therefore, the objectives of this study were 1) to elucidate the effects of CPB on perioperative immunoglobulin levels, and 2) to find out if alterations in lymphocyte subsets are related to these findings.

Proinflammatory and antiinflammatory cytokines after cardiac operation: different cellular sources at different times.

Background: Cardiac operation produces substantial alterations within the immune system, which possibly predispose postoperative complications. However, the interplay between proinflammatory and antiinflammatory reactions and the cells involved in this process are not completely clear. Therefore, we investigated serum levels, as well as synthesis patterns, of proinflammatory and antiinflammatory cytokines.

Alterations of cell-mediated immunity following cardiac operations: clinical implications and open questions.

Cardiac surgery with cardiopulmonary bypass (CPB) is known to induce an immune response whose nature has been increasingly elucidated during the recent decade. Clinically, patients usually show two to three of the four symptoms, which define the so-called systemic inflammatory response syndrome (SIRS). In addition, all parameters of the innate, nonspecific immune system, e.

Endothelialization of cardiac valve bioprostheses.

The main disadvantage of implanted xenograft valves used in cardiac surgery is their poor clinical long-term result, due to early tissue degeneration. In order to improve the performance of such glutaraldehyde fixed bioprostheses, a biological coating with viable endothelial cells was suggested. Therefore, glutaraldehyde preserved bovine pericard patches, as well as commercially available xenograft valves, were lined using human venous endothelial cells or microvascular cells from the subcutaneous fat tissue.