Quantitative monitoring of multi-donor chimerism after multi-donor allogeneic hematopoietic stem cell transplantation / 中国实验血液学杂志

This study was aimed to establish a model for detecting the donor chimerism rate following the multi-donor hematopoietic stem cell transplantations, and simplify its calculation method. Patients with hematologic disease receiving allogeneic hematopoietic stem cell transplantation including single-donor and multi-donor were selected in this study and the donor cell chimerism rates were detected, using STR-PCR combined with capillary electrophoresis. The results indicated that the peaks of the sister alleles coming from the same individual were confirmed to have the approximate areas and can be replaced each other in the situation of mixed chimerism. In the calculation model, the value between reference chimerism and approximate chimerism have no significant difference using the hypothetical peak areas, and the result was confirmed to be accepted basing on typical measurement error between sister alleles (5% - 20%). It is concluded that the areas of share peaks can be replaced by non-share peaks and this conclusion can be used to calculate the double-donor CHM (DD-CHM)(%). Compared to the D alleles, R alleles show more strategic importance because it can lead to more accurate result and allowed simplifying the arithmetic calculations for DD-CHM(%).

Gene therapy using a dominant negative form of the protein phosphatase 2A catalytic subunit a driven by a hepatoma tissue-specific promoter achieves effective growth inhibition of hepatoma cells / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To generate a gene delivery plasmid carrying the dominant negative form of the protein phosphatase 2A catalytic subunit a (DN-PP2Aca) driven by a hepatocellular carcinoma (HCC) tissue-specific promoter and investigate its ability to inhibit growth of cultured hepatoma cells.</p><p><b>METHODS</b>The gene delivery plasmid was constructed by PCR-amplifying DN-PP2Aca from wild-type PP2Aca using site-directed mutagenesis and then ligating the sequence-verified amplicon downstream of an alpha-fetoprotein enhancer and phosphoglycerate kinase promoter (AFpg) in the luciferase reporter vector pGL3-Basic. Following transfection into two AFP+ hepatoma cell lines (HepG2 and HepG3) and two AFP- hepatoma cell lines (SK-HEP-1 and L02), the transcriptional activity of the AFpg-driven DN-PP2Aca plasmid was tested using luciferase reporter gene assay and western blotting. The effect on cell growth was tested using MTT assay. Between group differences were assessed by t-test.</p><p><b>RESULTS</b>The AFpg-driven DN-PP2Aca plasmid showed high transcriptional activity and protein expression in both HepG2 and Hep3B cells. At 72 h after transfection, the proliferation capacities were repressed by 42.65%+/-3.99% (P = 0.0002) and 39.87%+/-3.91% (P = 0.0002) in AFP+ HepG2 and Hep3B cells, respectively (vs. untransfected). In contrast, the plasmid was transcriptionally inactive in and had no effect on proliferation of AFP- cells.</p><p><b>CONCLUSION</b>The AFpg-driven DN-PP2Aca plasmid exhibits selective cytotoxicity against AFP+ hepatoma cells, and may represent a useful gene therapy strategy to treat HCC.</p>