In vivo measurement of circulating leucocyte activation in patients following cardiopulmonary bypass.
We have developed a simple technique to measure in vivo activation of circulating leucocytes and assessed it in 6 patients undergoing cardiopulmonary bypass (CPB). Arterial, mixed venous, and jugular bulb blood samples were taken following i.v. [18F]FDG, before and after CPB. [18F]FDG uptake in leucocytes was measured by phosphor imaging of spun blood-filled capillary tubes. Leucocyte radioactivity was quantified ([(leucocytes-plasma)/plasma radioactivity] and normalised to leucocyte counts. [18F]FDG uptake (mean+/-SEM)) before CPB was undetectable, being -0.014+/-0.007, -0.011+/-0.003, -0.012+/-0.006, -0.010+/-0.005, whereas increased uptake was demonstrated following CPB, 0.006+/-0.006, 0.009+/-0.005, 0.021+/-0.005, 0.034+/-0.006, at 20, 40, 60, and 80 min, respectively. There was no significant difference in activation between sampling sites before or after CPB. This method gives a sensitive index of activation of circulating leucocytes in whole blood, enabling investigation of activation of circulating white cells without the influence of sample handling or the requirement for time-consuming cell separation procedures.
NHLI and Investigative Science, Faculty of Medicine, Imperial College, Hammersmith Campus, London, W12 0NN, United Kingdom. hazel.jones@imperial.ac.uk
Hazel A
HA
Jones
Marina
M
Choudhury
David N F
DN
Harris
D000328:Adult; D000368:Aged; D000465:Algorithms; D002315:Cardiopulmonary Bypass / Q000009:adverse effects* / Q000379:methods; D019788:Fluorodeoxyglucose F18 / Q000493:pharmacokinetics; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D007249:Inflammation / Q000000981:diagnostic imaging* / Q000209:etiology; D007958:Leukocyte Count / Q000379:methods*; D007962:Leukocytes / Q000000981:diagnostic imaging* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D018375:Neutrophil Activation; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18