Development of the therapy for hepatic congenital metabolic disease by In-Utero-Manipulation.

点击翻译按钮获取中文摘要

Rat fetal liver is a good model for choice to develop cell transplantation because the liver is under developmental and proliferative stage and visible through uteric memebrane. Amniotic epithelial cells, which we chose as donor cell this time, are proposed to be possible gene carrier into neural and hepatic tissue. The advantages of the cells are that 1) ethical problem are few, 2) there are neural and hepatic stem-like cells, 3) cells can be stored frozen, and 4) cells survive for relatively long-term. However, mass transplantation of amniotic cells via portal vein may cause embolism and the cells intrinsically proliferate only by two or three division in vitro. Therefore, we performed transplantation of amniotic cells into fetal liver. The certain population of the amniotic cells expressed albumin during culture period as was reported by human amniotic epithelial cells(J Hum Genet 45 171 2000). The cells can be stored frozen without marked impairment of viability. The cell division was 2.7 times at average and telomerase activity was detectable in the cells from fetuses at early stage(day 14), suggesting that telomerase transfection may accelerate cell proliferation. After cell transplantation(lacZ-transfected, 1〜8x10^6/10〜25μ1)to the liver of fetus(day18.5-20.5), 24-85% of the rats survived to be born. The transplanted cells were detectable in the liver at least 14 days after birth. The lacZ-positive cell remained longer with amniotic cell transplantation than direct injection of Ad-lacZ vector into fetal liver at the same stage. Therefore, present In-Utero-Manipulation will be useful strategy for cell mediated gene therapy for congenital liver disease.