Interleukin-10 and apoptotic death at circulating lymphocytes in surgical/anaesthesia trauma

Objective: To examine the relationship between circulating interleukin-10 ( IL-10) and the occurrence of lymphocyte apoptosis after surgical/anesthesia trauma. Methods: Data were collected prospectively on 18 adult patients undergoing elective major surgery. Blood sampling for assessment of lymphocyte apoptos is and IL-10 levels was performed on the day before surgery (t(0)) and at 2 4 and 96 hours after operation (t(1) and t(2), respectively). After lymphoc yte isolation, quantification of apoptosis was made by staining apoptotic c ells with 7-amino-actinonmycin D, Plasma IL-10 concentrations were measured using enzyme-linked immunosorbent assay, Results: A significantly increased frequency of apoptotic CD4(+) and CD8(+) cells (p < 0.05) was observed at t(1) measurement (8,10% +/- 0.58% and 12. 21% +/- 1.47% for CD4(+) and CD8+, respectively) compared with preoperative values (1.53% +/- 0.38% and 1.32% +/- 0.45% for CD4(+) and CD8(+), respect ively). Plasma IL-10 levels showed a significant elevation at both t(1) and t(2) times, peaking at t(1). At t(1), IL-10 levels were correlated with th e frequency of CD4(+) and CD8(+) apoptotic lymphocytes (r = 0.78, p = 0.000 5 for IL-10 vs. apoptotic CD4(+); r = 0.71, p = 0.003 for IL-10 vs. apoptot ic CD8(+)), Conclusion: surgical trauma is associated with a significant but transient increase in lymphocyte commitment to apoptosis and IL-10 production. The ex act relationship linking the overproduction of IL-10 with lymphocyte apopto sis after a surgical operation is still elusive and requires further invest igation.