A girl aged 6 years 9 months with severe heart disease secondary to homozygous familial hypercholesterolaemia underwent orthotopic cardiac transplantation and her liver was replaced with the liver of the same donor. In the first 10 weeks after transplantation serum cholesterol fell to 270 mg/dl from preoperative concentrations of more than 1000 mg/dl
Flow-cytometry analysis allowed the quantification of LDL receptors on monocytes isolated from both patients as compared with the mean value given by the kit
The amplified sequences coding for LDL-R and GAPDH from each patient were visualized following their electrophoretic migration in 1% agarose gel. As shown in Figure 4, the MDM obtained from FHC patient presented normal LDL-R gene expression. The domino recipient patient expressed LDL-R as well, but the expression was apparently diminished due to the fact that, in this case, the activation of monocytes was slightly reduced and this may explain the apparently diminished LDL-R expression in MDM obtained from the recipient patient (Fig.4).
These results were confirmed by the RT-PCR products from RNA isolated from primary culture fibroblasts obtained from the skin explants of patients A and B. The data showed the positive expression of mRNA coding for LDL-R in the fibroblasts of the two patients (Fig. 5).