Characterization of Familial Hypercholesterolemia Patient-Derived Hepatocyte-Like Cells

Friday, 13 February 2015
Exhibit Hall (San Jose Convention Center)
Kevin T. Tien, duPont Manual High School, Louisville, KY
Familial Hypercholesterolemia (FH) is a hereditary disease that results in defective expression of the Low Density Lipoprotein receptor (LDL-R). This condition yields cells that cannot bind or internalize LDL cholesterol (LDL). As a result, LDL accumulates in the bloodstream and accelerates atherosclerosis and cardiovascular disease. Liver transplant is regarded as the only curative therapy for FH patients, as liver hepatocytes have the highest density of LDL-R. As quality transplantable livers are in short supply, we wanted to create a liver-tissue mimic comprised of engineered hepatocytes, which are differentiated from induced pluripotent stem cells (iPSC). iPSC are desirable for their theoretically limitless supply and ability to differentiate into the three germ layers. FH patient-derived iPSC were differentiated into functional hepatocyte-like cells (HLC) over five distinct stages spanning 21 days. These stages expose the cells to a set sequence of growth factors and buffers designed to recapitulate native liver embryological development. PCRs were performed at the end of each differentiation stage to verify appropriate gene expression. The following six genes were assessed: POU5F1 (encodes the pluripotent marker OCT4), SOX17 and HNF4α (early and late endoderm markers, respectively), AFP (immature hepatocyte marker), ALBUMIN (mature hepatocyte marker), and GAPDH (control). Visualization of these PCR products via gel electrophoresis indicated that the cells expressed the appropriate markers for each stage of development, suggesting that we had successfully developed a population of patient-specific engineered hepatocytes.