FIGURE 1.

Distribution of CCK sensitivity in the patient population and its correlation with cellular cholesterol. Shown is a typical CCK concentration-response curve generated by measuring increase in intracellular calcium concentrations in leukocytes 24 h after transduction (A). The inset in panel A shows a representative image of the efficiency CCK1R expression achieved within this time as measured by GFP fluorescence. Histograms of the CCK EC₅₀ (B) and cellular cholesterol (C) distributions, with density curves for the total population included in the study (n = 112). Correlation plots between the CCK EC₅₀ on the x axis and cellular cholesterol (r = 0.4051, P = 0.000009) (D) or CCK1R expression level as measured by GFP fluorescence (r = −0.005468, P = 0.9569) (E) on the y axis. Spearman’s correlation test was used to obtain the r and P values. CCK, cholecystokinin; CCK1R, type 1 cholecystokinin receptor; Chol, cholesterol; EC₅₀, concentration stimulating one-half of the maximal response; GFP, green fluorescent protein; max, maximum; RFU, relative fluorescence unit.