White Paper: Effect Of Ex Vivo Storage On Human Peripheral Blood Neutrophil Expression Of CD11b And The Stabilizing Effects Of Cyto-Chex

CD11b (Mac-1, complement receptor 3) is the a sub-unit of the CD11/CD18 heterodimeric complex, which is one of a sub-family of three cell surface intergrin receptors sharing a common ß chain (ß2 or CD18). CD11b plays a key role in neutrophil localization at inflammatory sites and its expression is rapidly upregulated on neutrophil activation (Kishimoto et al., 1989). Expression of CD11b by peripheral blood neurophils has been used as an indicator of in vivo neutrophil activation in a number of studies. Upregulation of CD11b expression has been described in patients with occlusive arterial disease of the lower limb, suggesting this may be a marker of localized ischaemia reperfusion events in these individuals (Fossat et al., 1995). A different study using Ficoll-Hypaque separated cells has reported a reduction on the proportion of CD11b+ granulocytes following exercise in patients with peripheral arterial occlusive disease, suggesting that leukocyte-endothelial interactions occur during ischaemia (Ciufetti et al., 1994).