Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0043346 (xeroderma pigmentosum)
 2,924 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Nine lymphoblastoid cell lines were established after transformation by Epstein-Barr virus of peripheral lymphocytes from four xeroderma pigmentosum (XP) patients, the parents of one XP patient, and three normal donors. All these cell lines proliferate as suspension in Roswell Park Memorial Institute Medium 1640 supplemented with 20% fetal bovine serum, without detectable release of infectious Epstein-Barr virus. Some characteristics of these cell lines, such as growth rates, chromosome numbers, UV sensitivities, and activities of unscheduled DNA syntheses induced by UV, 4-nitroquinoline 1-oxide, and N-methyl-N'-nitro-N-nitrosoguanidine, were determined. Results confirm that the properties related to XP are not altered by transformation with Epstein-Barr virus and are the same in degrees of defect as are those of dermal fibroblasts from the respective individuals. These XP and normal lymphoblastoid cell lines should be especially useful for biochemical studies on the mechanism of DNA repair, because they are easy to grow in mass culture.
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PMID:A convenient method of establishing permanent lines of xeroderma pigmentosum cells. 20 81

Ten lymphoblastoid cell lines were established by Epstein-Barr virus-induced transformation directly from 0.04 to 0.15 ml of peripheral whole blood of one patient with xeroderma pigmentosum and four normal healthy adults. All these lines expressed B-lymphocyte characteristics. The advantages of this method are: (a) only a few drops of blood are required for establishing a permanent line; (b) damage and loss of cells in separation procedures are minimal; and (c) the method is simple, reliable, and applicable, if desired, to any patient, even babies.
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PMID:A greatly simplified method of establishing B-lymphoblastoid cell lines. 21 Sep 42

Lymphoblastoid cell lines were established after transformation by Epstein-Barr virus of peripheral lymphocytes from xeroderma pigmentosum (XP) patients and normal donors. These lines expressed B-lymphocyte characteristics. Typical characteristics related to XP of these cell lines were not altered by transformation. Extracts of these cells catalyzed release of uracil (Ura) and 3-methyladenine (3MeAde) from Ura-containing DNA (Ura-DNA) and methylated DNA (Me-DNA), respectively. These two activities, Ura-DNA glycosylase and 3MeAde-DNA glycosylase, differed in heat stability. Extracts released Ura more rapidly and 3MeAde more slowly from a single-stranded DNA than from a double-stranded DNA. On incubation with reconstituted chromatins prepared from Ura-DNA and Me-DNA, respectively, with calf thymus chromosomal protein, cell extracts released all the Ura but about half the 3MeAde residues. The activity levels of these two enzymes of XP cells were similar to those of normal cells.
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PMID:DNA glycosylases of human lymphoblastoid cells. 23 57

We have assessed the role of cellular transformation in ultraviolet (uv)-induced mutagenic events in human cells. To maintain uniformity of genetic background and to eliminate the effect of DNA repair, primary nontransformed lymphocytes (T-cells) and Epstein-Barr virus-transformed lymphocytes (B-cells) from one patient (XP12Be) with the DNA repair-deficient disorder xeroderma pigmentosum (group A) were transfected with the mutagenesis shuttle vector pZ189. Parallel control experiments were performed with primary, nontransformed lymphocytes from a normal individual and with a repair-proficient Epstein-Barr virus-transformed lymphocyte line (KR6058). pZ189 was treated with uv and introduced into the four cell lines by electroporation. Plasmid survival and mutations inactivating the marker supF suppressor tRNA gene in the recovered pZ189 were scored by transforming an indicator strain of Escherichia coli. Plasmid survival was reduced and mutation frequency elevated equally with both XP-A cell lines compared to both normal cell lines. Base sequence analysis of more than 250 independent plasmids showed that while the G:C----A:T base substitution mutation was found in at least 60% of plasmids with single or tandem mutations with all four cell lines, the frequency with the transformed XP-A (93%) cells was significantly higher (P less than 0.01) than that with the nontransformed XP-A cells (77%). In addition, with the transformed XP-A cells, there were significantly fewer plasmids with transversions and with mutations at a transversion hotspot (base pair 134) than with plasmids recovered from nontransformed XP-A cells. Interleukin-2 and phytohemagglutinin (used to maintain growth of the nontransformed lymphocytes) treatment of transformed XP12Be cells did not change overall plasmid survival or mutation frequency, but increased the transversion frequency and induced a mutational hotspot (at base pair 159), while another mutational hotspot (at base pair 123) disappeared. Thus we have demonstrated that in repair-deficient human cells, cellular transformation, while not affecting overall postuv plasmid survival and mutation frequency, does increase the susceptibility to G:C----A:T transition mutations, a type of mutation associated with uv-induced neoplasia.
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PMID:Ultraviolet mutagenesis in human lymphocytes: the effect of cellular transformation. 132 18

We constructed a human cDNA expression vector by combining an episomal Epstein-Barr virus (EBV) vector with the expression cassette from the transient-expression vector, pCDM8. This new vector, designated pEBS7, exhibited high-level expression of reporter genes in normal and repair-deficient xeroderma pigmentosum cell lines. Reconstruction experiments indicated that marker genes diluted to a frequency of 10(-5) can be rescued on a single transfection dish. Moreover, derivative cell lines that constitutively express the gene encoding EBV nuclear antigen 1 exhibited a tenfold enhancement in the frequency of rescue of marker genes. The feasibility of preparing large-scale directional or nondirectional cDNA libraries in pEBS7 was demonstrated and reconstruction experiments indicated that marker genes could be rescued from either library with equal efficiency. These results establish a high-efficiency system for the isolation of genes by direct phenotypic selection in human mutant cell lines.
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PMID:High-frequency transformation of human repair-deficient cell lines by an Epstein-Barr virus-based cDNA expression vector. 166 Aug 31

Cockayne syndrome (CS) and xeroderma pigmentosum (XP), autosomal recessive diseases with clinical and cellular hypersensitivity to UV radiation, differ in ability to repair UV DNA photoproducts in their overall genome: normal repair in CS, defective repair in XP. In order to characterize a DNA repair defect in an active gene in CS, we measured the capacity of cells from patients with CS and XP to reactivate 2 major types of UV-induced DNA damage, photoreactivatable (i.e., cyclobutane pyrimidine dimers) and non-photoreactivatable (primarily pyrimidine-(6-4)pyrimidone photoproducts), in the actively transcribing chloramphenicol acetyltransferase (cat) gene of the plasmid expression vector pRSV-cat. Epstein-Barr virus-transformed lymphoblast lines from 4 normal persons and from 3 patients with CS and from two with XP were transiently transfected with the plasmid, and the cat activity in cell extracts was determined. When the cells were transfected with UV-irradiated plasmid, expression was abnormally decreased in both the CS and XP cells. When the cyclobutane pyrimidine dimers in the UV-irradiated plasmid were removed by photoreactivation prior to transfection, cat expression in the CS, but not in the XP, lines reached normal levels. These data imply that both the XP and CS cells are unable to repair normally the cyclobutane pyrimidine dimer photoproducts which block transcription of cat. However, the CS, but not XP, cells can repair normally the other UV-induced photoproducts which block transcription. The ability of CS, but not XP, cells to repair these non-dimer photoproducts indicates that the active gene repair mechanism treats the cyclobutane pyrimidine dimer differently from the non-dimer photoproducts.
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PMID:Evidence for defective repair of cyclobutane pyrimidine dimers with normal repair of other DNA photoproducts in a transcriptionally active gene transfected into Cockayne syndrome cells. 171

In order to examine possible cell-type specificity in mutagenic events, a shuttle-vector plasmid, pZ189, carrying a bacterial suppressor tRNA marker gene, was treated with ultraviolet radiation and propagated in Epstein-Barr virus transformed lymphoblastoid cell lines from a patient, XP12BE, with xeroderma pigmentosum (XP), group A, and a normal control. XP is a skin-cancer-prone disorder with UV hypersensitivity and defective DNA repair. Plasmid survival and mutations inactivating the marker gene were scored by transforming an indicator strain of E. coli. An earlier report on this data [Seetharam et al., (1990) J. Mol. Biol., 212, 433] indicated lower survival and higher mutation frequency with the UV-treated plasmid passed through the XP12Be(EBV) line. In the present report, sequence analysis of 198 mutant plasmids revealed a predominance of G:C----A:T transitions with both lymphoblastoid cell lines. This finding is consistent with the bias of polymerases toward insertion of an adenine opposite non-coding photoproducts (dinucleotides or other lesions). Transversion mutagenesis, non-adjacent double mutations, and triple-base mutations may involve other mechanisms. These results were compared to similar data from a fibroblast line from the same patient [Bredberg et al., (1986) Proc. Natl. Acad. Sci. (U.S.A.), 83, 8273]. The frequency of G:C----A:T transitions was higher, and there were fewer plasmids with multiple-base substitutions and with transversion mutations with both XP lymphoblasts and fibroblasts than with the normal lymphoblasts and fibroblasts. There were no significant differences in classes or types of mutations in the UV-treated plasmid replicated in the XP lymphoblasts and the XP fibroblasts. This suggests that the major features of UV mutagenesis in different cell types from the same individual are similar.
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PMID:Ultraviolet mutational spectrum in a shuttle vector propagated in xeroderma pigmentosum lymphoblastoid cells and fibroblasts. 198 77

Xeroderma pigmentosum complementation group A (XPA) is one of the DNA repair deficient syndromes. The cell biological features of XPA were examined by flowcytometry using Epstein Barr (EB) virus-transformed lymphoblastoid cells. Cellular sensitivity to vincristine (VCR), etoposide (VP-16) and methotrexate (MTX) were assayed by DNA pattern changes by flowcytometry. Recently, ataxia-telangiectasia (AT), one of the same kind of disorder, has been reported to have an increased sensitivity to VCR and VP-16. However, AT showed some resistance to MTX according to other reports. Our results showed that XPA had an increased sensitivity to VCR and also to VP-16. Moreover, different from AT, XPA showed some sensitivity to MTX. Thus there is some cell biological similarity between XPA and AT, as well as some difference of the abnormality in the DNA repair pathway.
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PMID:Flowcytometric analysis of DNA pattern of cells derived from xeroderma pigmentosum A--hypersensitivity to vincristine, etoposide and methotrexate. 223 99

The present studies confirm that diesel exhaust emissions are mutagenic in bacterial and mammalian mutation assays. Our results further indicate that mutagenic potential of the diesel tar samples can be reduced by exogenous metabolic activation with S15, and that Epstein-Barr-virus transformed lymphoblastoid cell lines from Bloom syndrome, and Xeroderma Pigmentosum patients with a high incidence of malignant tumors showed an larger production of SCEs while those from Fanconi anemia patients had an lower frequency of SCEs when exposed to the diesel emission condensate, compared to those from normal healthy persons. On the contrary to the results of in-vitro studies, the in-vivo SCE and micronucleus assays using mouse and rat bone marrow cells gave negative responses.
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PMID:Genotoxicity of diesel exhaust emissions in a battery of in-vitro short-term and in-vivo bioassays. 243 8

A cDNA expression vector containing the element oriP and the sequence encoding the Epstein-Barr virus (EBV) nuclear antigen 1 (EBNA-1) as well as the hygromycin B-resistance dominant marker gene has been constructed. Its characteristics have been compared to a similar vector lacking the EBV sequences. (a) The EBV+ vector is maintained as an episome with a copy number of approx. 50 per cell, whereas the number of the integrated EBV- copies is in general smaller than 10, when simian virus 40-transformed xeroderma pigmentosum fibroblasts (XP20S-SV) constitute the recipient cell line. (b) The presence of the EBV sequences in the vector resulted in a five- to ten-fold higher transfection efficiency with the Ca.phosphate precipitation technique. (c) cDNA inserts in the EBV+ vector are shown to be efficiently and properly expressed in the recipient cell. (d) If transfection is performed with a mixture of EBV+ vectors with different inserts, transfectants are shown to harbour different plasmids within one cell. (e) The ratio between these plasmids in one cell can be shifted in favour of a vector with a particular insert, when selection for this insert is performed. (f) Reconstruction experiments indicated that isolation of a low-abundance sequence from a mixture of vectors is at least 100-fold more efficient with the EBV+ system, than with the EBV- system. (g) Rescue of the episomal vector from transfected cells can be readily achieved.
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PMID:Construction and properties of an Epstein-Barr-virus-derived cDNA expression vector for human cells. 248 30


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