Blood viscosity and the expression of inflammatory and adhesion markers in homozygous sickle cell disease subjects with chronic leg ulcers

To determine differences in TNF-α, IL-1β, IL-10, sICAM-1 concentrations, leg hypoxia and whole blood viscosity (WBV) at shear rates of 46 sec(-1) and 230 sec(-1) in persons with homozygous S sickle cell disease (SCD) with and without chronic leg ulceration and in AA genotype controls. & fifty-five age-matched participants were recruited into the study: 31 SS subjects without leg ulcers (SSn), 24 SS subjects with leg ulcers (SSu) and 18 AA controls. Haematological indices were measured using an AC.Tron Coulter Counter. Quantification of inflammatory, anti-inflammatory and adhesion molecules was performed by ELISA. Measurement of whole blood viscosity was done using a Wells Brookfield cone-plate viscometer. Quantification of microvascular tissue oxygenation was done by Visible Lightguide spectrophotometry. TNF-α and whole blood viscosity at 46 sec(-1) and 230 sec(-1) (1.75, 2.02 vs. 0.83, 1.26, p