Chromosomal Instability in Lymphoblastoid Cell Lines Derived from Patients with Different Inherited disorders

EB病毒介导淋巴细胞转化建立的永久性生长淋巴母细胞样细胞系（LCL）在临床和实验人类遗传学中都具有重要的实用价值。我们已经建立了一系列来自各种遗传性疾病患者或家庭的LCL。为了证实它们的有效性，并获得维持LCL的基本准则，我们对这些LCL在长时间培养过程中的细胞遗传学特性进行了研究。结果表明：1)近2年来建立的LCL包括：家族性大肠息肉病（FPC） 36个家族87个系，多发性内分泌肿瘤2型（MEN2） 6个家族24个系，遗传性脆性位点（FS）携带者19个系，各种染色体异常患者14个系。2)对来自MEN2家族和FS携带者的LCL进行延长培养（2个月~ 1.5年）的核型分析。一般来说，获得性染色体异常在建立后4个月发生，无论其遗传来源（年龄、社会地位、携带者或非携带者）如何。在一些体外培养1年以上的LCL中，几乎所有细胞的核型都出现异常，克隆染色体发生改变。异常多为数字型，以5号、8号、12号和15号染色体三体为主。3)可遗传FS载体在LCL中的FS表达率一般很低（<3%），但rdu所需的fra(10)（q25）载体衍生的细胞系“B-3”在暴露于5-溴脱氧尿苷（7<micrn>g/ml） 24小时后，FS的表达率很高（40-60%）。4)在环状染色体r（18）和r（21）的LCL患者中，即使延长培养4个月，环状染色体仍然保留。这表明了小尺寸染色体参与的环的形态稳定性。5)本文建立的部分LCL有效地用于克隆DNA片段（D13S21、D13S22和D18S5）的区域定位。来自MEN2和FPC家族的LCL可用于连锁分析和肿瘤中本构杂合性缺失的研究。6)利用细胞系“B-3”进行实验，发现胸腺嘧啶的fra(10)（p25）表达分布在fra（10）位点的两条DNA双链之间。少

Permanent growing lymphoblastoid cell lines (LCL) established by EB virus-mediated transformation of lymphocytes are now of great practial value in both clinical and experimental human genetics. We have established a series of LCL from patitents or families with various hereditary diseases. In order to confirm their availability and to obtain the basic guidelines for the maintenance of LCL, we have examined cytogenetic characters of these LCL in the course of prolonged culture condition. The results are as follows:1) The LCL established for the last 2 years include: 87 lines from 36 families with familial polyposis coli (FPC), 24 lines from 6 families with multiple endocrine neoplasia type 2 (MEN2), 19 lines from heritable fragile site (FS) carriers, and 14 lines from patients with various chromosomal abnormalities.2) Karyotype analyses were made on prolonged cultures (2 months to 1.5 year) of LCL from MEN2 families and from FS carriers. In general,acquired chromosome abnormalities app … More eared four months after the establishment, regardless of their genetic sources (age, ses, carriers or noncarriers). In some of the LCL maintained in vitro for more than one year, almost all of the cells showed abnormal karyotypes with clonal chromosome changes. The abnormalities were mostly of numerical type with a predominance of trisomies of Nos. 5, 8, 12 and 15 chromosomes.3) Expression rates of FS in LCL derived from heritable FS carriers were in general very low (<3%), but a cell line "B-3",derived froma RdU-required fra(10)(q25) carrier, expressed the FS with high frequencies (40-60%) after exposure to 5-bromodeoxyuridine (7<micrn>g/ml) for 24 hours. 4) In LCL from patients with a ring chromosome, r(18) and r(21), respectively, the rings were retained even after prolonged culture for 4 months. This indicates the morphological stability of the rings in which the small-sized chromosomes were involved.5) Some of the LCL here establsihed were efficiently employed for regional mapping of cloned DNA segments (D13S21), D13S22 and D18S5). The LCL from MEN2 and FPC families could be applied to the linkage analysis and to the esarch inn tumors for somatic loss of constitutinal heterozygosity.6) In experiments using the cell line "B-3", it was found that the fra(10)(p25) expression distribution of thymine between the two strands of DNA duplex in the fra(10) site. Less