Flow cytometric evaluation of T cell activation markers after cardiopulmonary bypass.
Background. Cardiopulmonary bypass surgery (CPBS) is associated with an increased risk for infections or with subsequent organ dysfunction. As T cell activation is a central mechanism during inflammatory processes, we developed an assay to evaluate T cell activation pathways in patients undergoing CPBS. Methods. Blood was obtained from eleven patients undergoing CPBS preoperatively, on postoperative day (POD)-3, and on POD-7 and was stimulated with different concentrations of Concanavalin A (ConA). Cyclosporine and sirolimus, inhibiting different pathways of the T cell cycle, were added to blood ex vivo. Expression of T cell activation markers CD25 and CD95 was analyzed by flow cytometry. Results. In untreated blood, expression of CD25 and CD95 significantly increased with higher ConA concentrations (P < 0.05) and decreased for all ConA concentrations for both antigens over the study time (P < 0.05). Independently from the ConA concentration, inhibition of CD25 and CD95 expression was highest preoperatively for sirolimus and on POD-3 for cyclosporine. At all time points, inhibition of CD25 and CD95 expression was significantly higher after cyclosporine compared to sirolimus treatment (P < 0.001). Conclusion. Our results showed that different pathways of T cell activation are impaired after CPBS. Such knowledge may offer the opportunity to identify patients at risk for postoperative complications.
University Hospital Leipzig, Heart Center, Department of Cardiac Surgery, 04289 Leipzig, Germany.
Maja-Theresa
MT
Dieterlen
Florida Hospital Orlando, Department of Cadiothoracic Transplantation and Advanced Cardiac Surgery, Orlando, FL 32803, USA.
Hartmuth B
HB
Bittner
University Hospital Leipzig, Heart Center, Department of Pediatric Cardiology, 04289 Leipzig, Germany.
Attila
A
Tarnok
University Hospital Leipzig, Heart Center, Department of Cardiac Surgery, 04289 Leipzig, Germany.
Jens
J
Garbade
University Hospital Leipzig, Heart Center, Department of Cardiac Surgery, 04289 Leipzig, Germany.
Stefan
S
Dhein
University Hospital Leipzig, Heart Center, Department of Cardiac Surgery, 04289 Leipzig, Germany.
Friedrich W
FW
Mohr
University Hospital Leipzig, Heart Center, Department of Cardiac Surgery, 04289 Leipzig, Germany.
Markus J
MJ
Barten