Zimmer N, Göttert E, Kraus J, Zang K D, Henn W
Institut für Humangenetik, Universität des Saarlandes, Homburg, Saar, Germany.
Hum Genet. 1993 May;91(4):317-20. doi: 10.1007/BF00217349.
Chromosomal mosaicism in chorionic villus samples (CVS) may arise from different sources, such as clonal diversity within the chorionic tissue or contamination with maternal cells. To determine the origin of karyotyped cells, we compared the immunocytochemical features of mitotic cells in CVS long-term cultures with histological sections of their tissue of origin, i.e. chorionic villi. Immunolabelling of intermediate filaments specific for epithelial cells (cytokeratin) and mesenchymal cells (vimentin) established that mitoses yielded from CVS long-term cultures indeed stem from independently growing clones derived from both the epithelial and mesenchymal parts of the chorionic villi. Thus, mosaicism in CVS cultures may reflect true genetic heterogeneity within the biopsy. However, epithelial chorionic cells undergo in vitro metaplasia leading to co-expression of cytokeratins and vimentin. Fetal-specific immune markers (beta-HCG and SP1-glycoprotein) are not reliably expressed in CVS cell culture.
绒毛膜绒毛样本（CVS）中的染色体嵌合现象可能源于不同的来源，如绒毛膜组织内的克隆多样性或母体细胞的污染。为了确定核型细胞的起源，我们将CVS长期培养中有丝分裂细胞的免疫细胞化学特征与其起源组织即绒毛膜绒毛的组织切片进行了比较。对上皮细胞（细胞角蛋白）和间充质细胞（波形蛋白）特异的中间丝进行免疫标记，证实CVS长期培养产生的有丝分裂确实源于绒毛膜绒毛上皮和间充质部分独立生长的克隆。因此，CVS培养中的嵌合现象可能反映活检组织内真正的基因异质性。然而，绒毛膜上皮细胞在体外会发生化生，导致细胞角蛋白和波形蛋白的共表达。胎儿特异性免疫标志物（β-人绒毛膜促性腺激素和SP1糖蛋白）在CVS细胞培养中不能可靠表达。
