Human sera of low and high CRP sub-groups differentially affect cholesterol efflux. (A) Sera of subjects consuming walnut oil affect cholesterol efflux. Following the induction of foam cells, human sera (10%, v:v) of baseline and 4 h postprandially were applied as treatment to induce cholesterol efflux for 24 h. Following efflux period, control cells (incubated in serum-free culture medium only) had a cholesterol efflux of 5.4%. The value is normalized and expressed as 100%. (B) Categorized by baseline CRP (cut point of 2 mg/L), changes of cholesterol efflux following treatment by human sera of walnut oil group. Experiment conditions were as described in Figure 3B. Symbol * indicates a significant difference between control and treatment groups (P < 0.05). Results are representative of two independent experiments with a duplicate at each time point (baseline and 4 h postprandially) of each subject.