Effect of the triolein enrichment on the protein dissociation and thermal remodeling of plasma HDL. (A) SEC (Superdex 16 XK column) of the incubation mixture containing CETP, TO:POPC emulsions and HDL (CETP-TO-HDL), which were prepared as described in Methods, and of nHDL shows dissociation of an apolipoprotein fraction from HDL upon enrichment in TO under ambient conditions. (B) Thin-layer chromatography of TO-HDL isolated from the incubation mixture shows an increased amount of TO as compared to nHDL. (C) Differential scanning calorimetry of TO-HDL that have been isolated from the CETP-TO-HDL incubation mixture and of nHDL. Heat capacity data, Cp(T), show that TO enrichment leads to low-temperature shifts in HDL fusion and rupture transitions (rupture temperatures are indicated by dotted lines). (D) Native PAGE of nHDL and TO-HDL, which have been heated to 90 °C to trigger lipoprotein fusion, shows more extensive lipoprotein fusion and protein dissociation in TO-HDL.