Endotoxemia during supraceliac aortic crossclamping is associated with suppression of the monocyte CD14 mechanism: possible role of transforming growth factor-beta1.
OBJECTIVE
Monocyte CD14 and its soluble form (sCD14) mediate the proinflammatory response to endotoxemia. The aim of this study was to measure the changes to these factors after major aortic surgery and the possible inhibitory role of transforming growth factor-beta(1) (TGF-beta(1)) during these procedures.


METHODS
Twenty-four patients with supraceliac aortic crossclamping during thoracoabdominal aortic aneurysm (TAAA) repair and 12 patients with infrarenal aortic crossclamping as part of infrarenal aneurysm repair (AAA) were studied. Blood was collected at incision, aortic clamping, and reperfusion and at 1, 8, and 24 hours after reperfusion. Samples were assayed for endotoxin, peripheral blood monocyte CD14 expression, sCD14, tumor necrosis factor-alpha, and TGF-beta(1).


RESULTS
Although there was significant endotoxemia on reperfusion in both groups of patients, peak plasma endotoxin levels were significantly higher in patients with TAAA (P =.001). Monocyte CD14 and plasma sCD14 were significantly decreased in patients with TAAA at reperfusion and 1 hour after reperfusion (P <.01, both points). In patients with AAA, a significant upregulation of CD14 was observed at 24 hours after reperfusion (P <.01), but no significant changes in sCD14 were observed. TNF-alpha showed no significant changes during the study period in both groups. In patients with TAAA, TGF-beta(1) showed significant elevation at all time points (P <.01); whereas in patients with AAA, TGF-beta(1) showed no significant changes.


CONCLUSIONS
Splanchnic ischemia reperfusion in patients who undergo supraceliac aortic clamping is associated with peripheral blood monocyte CD14 suppression and significant elevation of TGF-beta(1). TGF-beta(1) may play an important role in modulating the immune response to endotoxemia during major aortic aneurysm surgery.
Hafez
H M
HM
Academic Surgical and Regional Vascular Unit, Division of Surgery and Anaesthetics, Imperial College Medical School at St Mary's Hospital, London, United Kingdom.
Berwanger
C S
CS
Lintott
P
P
Delis
K
K
Wolfe
J H
JH
Mansfield
A O
AO
Stansby
G
G
D000368:Aged; D017544:Aortic Aneurysm, Abdominal / Q000097:blood / Q000601:surgery*; D017545:Aortic Aneurysm, Thoracic / Q000097:blood / Q000601:surgery*; D019446:Endotoxemia / Q000276:immunology / Q000378:metabolism*; D005260:Female; D006801:Humans; D007108:Immune Tolerance; D007432:Intraoperative Period; D007963:Leukocytes, Mononuclear / Q000378:metabolism; D018950:Lipopolysaccharide Receptors / Q000378:metabolism*; D008297:Male; D015424:Reperfusion; D013152:Splanchnic Circulation; D016212:Transforming Growth Factor beta / Q000502:physiology*
D018950:Lipopolysaccharide Receptors; D016212:Transforming Growth Factor beta