Figure 6. ABCA1 CEC (A), HDL particle size distribution (B), free cholesterol (C) and total cholesterol (D) content of control and LCAT-deficient plasma incubated with LCAT.

Control plasma (N=3) and LCAT-deficient plasma (N=3) were incubated with and without recombinant human LCAT (rLCAT+ and rLCAT−; 50 μg/mL) for 1 h at 37^⁰C. The LCAT reaction was stopped with 2 mM DTNB and cooling on ice. Control studies demonstrated that DTNB did not alter the CEC of plasma. DTNB was omitted from plasma used to quantify cholesterol levels because it interfered with the enzymatic assay. ABCA1 CEC of plasma was quantified using [³H]cholesterol-labeled BHK cells as described in the legend to Fig. 5. P-values, ratio-t test.