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Sample records for cell clones isolated

  1. Isolation and characterization of variant clones of Chinese hamster cells after treatment with irradiated 5-iodouridine

    International Nuclear Information System (INIS)

    Kuroda, Y.; Yokoiyama, A.; Kada, T.

    1975-01-01

    Variant clones were isolated from cultured Chinese hamster Don cells after treatment with irradiated 5-iodouridine. The following characters of a primary variant clone, C-11 and a secondary variant clone, C-24 were compared with those of the original clone C-1: colony-forming activity, growth rate in the presence of irradiated and unirradiated 5-iodouridine, distribution of chromosome numbers and cell cohesion. The variant clones C-11 and C-24 were partially resistant to unirradiated 5-iodouridine at lower concentration and C-24 cells were slightly resistant to short-term treatment with irradiated 5-iodouridine. Unlike clones C-1 and C-11, the variant clone C-24 showed no lag phase on growth in 5-iodouridine medium. The modal numbers of the chromosomes of all three clones were 22, like that of normal Chinese hamster diploid cells. Of the three clones, the variant C-24 cells showed the least mutual cohesion and the original C-1 cells showed the most. The possibility that an alteration in cellular membrane might be related to an increase in the resistance to radiosensitizing agents was discussed

  2. Cloning of Plasmodium falciparum by single-cell sorting.

    Science.gov (United States)

    Miao, Jun; Li, Xiaolian; Cui, Liwang

    2010-10-01

    Malaria parasite cloning is traditionally carried out mainly by using the limiting dilution method, which is laborious, imprecise, and unable to distinguish multiply-infected RBCs. In this study, we used a parasite engineered to express green fluorescent protein (GFP) to evaluate a single-cell sorting method for rapidly cloning Plasmodium falciparum. By dividing a two-dimensional scattergram from a cell sorter into 17 gates, we determined the parameters for isolating singly-infected erythrocytes and sorted them into individual cultures. Pre-gating of the engineered parasites for GFP allowed the isolation of almost 100% GFP-positive clones. Compared with the limiting dilution method, the number of parasite clones obtained by single-cell sorting was much higher. Molecular analyses showed that parasite isolates obtained by single-cell sorting were highly homogenous. This highly efficient single-cell sorting method should prove very useful for cloning both P. falciparum laboratory populations from genetic manipulation experiments and clinical samples. Copyright 2010 Elsevier Inc. All rights reserved.

  3. Cloning of Plasmodium falciparum by single-cell sorting

    Science.gov (United States)

    Miao, Jun; Li, Xiaolian; Cui, Liwang

    2010-01-01

    Malaria parasite cloning is traditionally carried out mainly by using the limiting dilution method, which is laborious, imprecise, and unable to distinguish multiply-infected RBCs. In this study, we used a parasite engineered to express green fluorescent protein (GFP) to evaluate a single-cell sorting method for rapidly cloning Plasmodium falciparum. By dividing a two dimensional scattergram from a cell sorter into 17 gates, we determined the parameters for isolating singly-infected erythrocytes and sorted them into individual cultures. Pre-gating of the engineered parasites for GFP allowed the isolation of almost 100% GFP-positive clones. Compared with the limiting dilution method, the number of parasite clones obtained by single-cell sorting was much higher. Molecular analyses showed that parasite isolates obtained by single-cell sorting were highly homogenous. This highly efficient single-cell sorting method should prove very useful for cloning both P. falciparum laboratory populations from genetic manipulation experiments and clinical samples. PMID:20435038

  4. Analysis of the factors in determining radiosensitivity in mammalian cells by using radio-sensitive and -resistant clones isolated from HeLa S3 cells in vitro

    International Nuclear Information System (INIS)

    Nikaido, Osamu; Horikawa, Masakatsu

    1976-01-01

    The factors in determining radiosensitivity of cultured mammalian cells were analysed by using two clones each having different radiosensitivities. The radiosensitive clones were isolated from HeLa S3 cells by the N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-treatment, X-irradiation (200 R) and 5-bromodeoxyuridine (BUdR)-visible light method. On the other hand, the radioresistant clone was isolated by single X-irradiation (2000 R) from MNNG-treated HeLa S3 cell population. The radiosensitivities expressed in D sub(o) and D sub(q) values were 110 and 140 R in radiosensitive SM-1a clone and 180 and 230 R in radioresistant RM-1b clone respectively. The biological and biochemical characteristics of both clones such as the distribution of chromosome numbers, formation and rejoining of single strand breaks in DNA caused by X-irradiation, non-protein sulfhydryl (NPSH) and apparent total sulfhydryl (APSH) contents were measured. Among the characteristics analysed, different contents of NPSH in the cell were well correlated to their daiosensitivities among the original HeLa S3 cells, SM-1a and RM-1b clone. Additionally, it was found that the radioresistant L.P3 Co-3 cells isolated by Tsuboi et al. from the original mouse L.P3 cells by means of serial irradiation with 60 Co γ-rays have more abundant NPSH than the original L.P3 cells. From these results, it can be concluded that the amount of NPSH play the main role in determining radiosensitivity in cultured mammalian cells. (auth.)

  5. A method for the isolation and characterization of functional murine monoclonal antibodies by single B cell cloning.

    Science.gov (United States)

    Carbonetti, Sara; Oliver, Brian G; Vigdorovich, Vladimir; Dambrauskas, Nicholas; Sack, Brandon; Bergl, Emilee; Kappe, Stefan H I; Sather, D Noah

    2017-09-01

    Monoclonal antibody technologies have enabled dramatic advances in immunology, the study of infectious disease, and modern medicine over the past 40years. However, many monoclonal antibody discovery procedures are labor- and time-intensive, low efficiency, and expensive. Here we describe an optimized mAb discovery platform for the rapid and efficient isolation, cloning and characterization of monoclonal antibodies in murine systems. In this platform, antigen-binding splenic B cells from immunized mice are isolated by FACS and cocultured with CD40L positive cells to induce proliferation and mAb production. After 12days of coculture, cell culture supernatants are screened for antigen, and IgG positivity and RNA is isolated for reverse-transcription. Positive-well cDNA is then amplified by PCR and the resulting amplicons can be cloned into ligation-independent expression vectors, which are then used directly to transfect HEK293 cells for recombinant antibody production. After 4days of growth, conditioned medium can be screened using biolayer interferometry for antigen binding and affinity measurements. Using this method, we were able to isolate six unique, functional monoclonal antibodies against an antigen of the human malaria parasite Plasmodium falciparum. Importantly, this method incorporates several important advances that circumvent the need for single-cell PCR, restriction cloning, and large scale protein production, and can be applied to a wide array of protein antigens. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Late post-irradiation phenomena in mammalian cell populations. Pt. 3. Characteristics of the slowly growing clones isolated from X-irradiated L5178Y-S cell cultures

    International Nuclear Information System (INIS)

    Beer, J.Z.; Szumiel, I.

    1975-01-01

    Populations of murine leukaemic lymphoblasts L5178Y-S irradiated with 300 rads of X-rays in vitro were analysed by serial clonings. It was found that the latent radiation-induced heritable lesions can be revealed by this technique. Approximately 100 slowly growing cell sublines with doubling times varying from 12 to 25 h, obtained by cloning, were assayed for: viability, cloning efficiency, mitotic index, labelling index (1 h and 24 h exposure to 3 H-thymidine), 3 H-thymidine incorporation rate, histone Fl phosphorous content, radiosensitivity, cell cycle disturbances, DNA per cell content, karyotype changes. The slowly-growing clones show normal or almost normal viability but have reduced cloning efficiencies. No correlations were found between the subline's doubling time or time interval between its isolation and determination, on one hand, and mitotic index or 1 h labelling index, on the other hand. 3 H-thymidine incorporation rate and histone Fl phosphorylation degree were inversely related to the subline's doubling time. Increased radiosensitivity of the slowly growing sublines, observed soon after their isolation, indicates that the heritable lesions in the cells studied are radiation-induced rather than selected. Autoradiographic analysis of the cell cycle indicates: heterogeneity of the slowly growing cell lines, occurence of cells with prolonged G2 phase and a possibility that in more severely damaged cells S phase is also affected. (author)

  7. Cell cloning-on-the-spot by using an attachable silicone cylinder.

    Science.gov (United States)

    Park, Hong Bum; Son, Wonseok; Chae, Dong Han; Lee, Jisu; Kim, Il-Woung; Yang, Woomi; Sung, Jae Kyu; Lim, Kyu; Lee, Jun Hee; Kim, Kyung-Hee; Park, Jong-Il

    2016-06-10

    Cell cloning is a laboratory routine to isolate and keep particular properties of cultured cells. Transfected or other genetically modified cells can be selected by the traditional microbiological cloning. In addition, common laboratory cell lines are prone to genotypic drift during their continual culture, so that supplementary cloning steps are often required to maintain correct lineage phenotypes. Here, we designed a silicone-made attachable cloning cylinder, which facilitated an easy and bona fide cloning of interested cells. This silicone cylinder was easy to make, showed competent stickiness to laboratory plastics including culture dishes, and hence enabled secure isolation and culture for days of selected single cells, especially, on the spots of preceding cell-plating dishes under microscopic examination of visible cellular phenotypes. We tested the silicone cylinder in the monoclonal subcloning from a heterogeneous population of a breast cancer cell line, MDA-MB-231, and readily established independent MDA-MB-231 subclones showing different sublineage phenotypes. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. T-cell libraries allow simple parallel generation of multiple peptide-specific human T-cell clones.

    Science.gov (United States)

    Theaker, Sarah M; Rius, Cristina; Greenshields-Watson, Alexander; Lloyd, Angharad; Trimby, Andrew; Fuller, Anna; Miles, John J; Cole, David K; Peakman, Mark; Sewell, Andrew K; Dolton, Garry

    2016-03-01

    Isolation of peptide-specific T-cell clones is highly desirable for determining the role of T-cells in human disease, as well as for the development of therapies and diagnostics. However, generation of monoclonal T-cells with the required specificity is challenging and time-consuming. Here we describe a library-based strategy for the simple parallel detection and isolation of multiple peptide-specific human T-cell clones from CD8(+) or CD4(+) polyclonal T-cell populations. T-cells were first amplified by CD3/CD28 microbeads in a 96U-well library format, prior to screening for desired peptide recognition. T-cells from peptide-reactive wells were then subjected to cytokine-mediated enrichment followed by single-cell cloning, with the entire process from sample to validated clone taking as little as 6 weeks. Overall, T-cell libraries represent an efficient and relatively rapid tool for the generation of peptide-specific T-cell clones, with applications shown here in infectious disease (Epstein-Barr virus, influenza A, and Ebola virus), autoimmunity (type 1 diabetes) and cancer. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  9. Hope for restoration of dead valuable bulls through cloning using donor somatic cells isolated from cryopreserved semen.

    Directory of Open Access Journals (Sweden)

    Naresh L Selokar

    Full Text Available Somatic cells were isolated from cryopreserved semen of 4 buffalo bulls, 3 of which had died over 10 years earlier, and were established in culture. The cells expressed cytokeratin-18, keratin and vimentin indicating that they were of epithelial origin. The cells were used as nuclear donors for hand-made cloning for producing buffalo embryos. The blastocyst rate and quality, as indicated by apoptotic index, were comparable among embryos produced using cells obtained from fresh or frozen-thawed semen or those obtained from conventional cell sources such as skin. Examination of the epigenetic status revealed that the global level of H3K27me3 but not that of H3K9/14ac and H4K5ac differed significantly (P<0.05 among cloned embryos from different bulls. The relative mRNA abundance of HDAC1, DNMT1, P53 and CASPASE 3 but not that of DNMT3a differed in cells and in cloned embryos. Following transfer of 24 cloned embryos produced from fresh semen-derived cells to 12 recipients, one calf weighing 55 kg, which is now 6 months of age and is normal, was born through normal parturition. Following transfer of 20 embryos produced from frozen-thawed semen-derived cells to 10 recipients, 2 became pregnant, one of which aborted in the first trimester; the calf born was severely underweight (17 kg, and died 12 h after birth. The ability of cells derived from fresh and frozen-thawed semen to produce live offspring confirms the ability of these cells to be reprogrammed. Our findings pave the way for restoration of highly precious progeny-tested bulls, which has immense economic importance, and can also be used for restoration of endangered species.

  10. Cloning the interleukin 1 receptor from human T cells

    International Nuclear Information System (INIS)

    Sims, J.E.; Acres, R.B.; Grubin, C.E.; McMahan, C.J.; Wignall, J.M.; March, C.J.; Dower, S.K.

    1989-01-01

    cDNA clones of the interleukin 1 (IL-1) receptor expressed in a human T-cell clone have been isolated by using a murine IL-1 receptor cDNA as a probe. The human and mouse receptors show a high degree of sequence conservation. Both are integral membrane proteins possessing a single membrane-spanning segment. Similar to the mouse receptor, the human IL-1 receptor contains a large cytoplasmic region and an extracellular, IL-1 binding portion composed of three immunoglobulin-like domains. When transfected into COS cells, the human IL-1 receptor cDNA clone leads to expression of two different affinity classes of receptors, with K a values indistinguishable from those determined for IL-1 receptors in the original T-cell clone. An IL-1 receptor expressed in human dermal fibroblasts has also been cloned and sequenced and found to be identical to the IL-1 receptor expressed in T cells

  11. Endangered wolves cloned from adult somatic cells.

    Science.gov (United States)

    Kim, Min Kyu; Jang, Goo; Oh, Hyun Ju; Yuda, Fibrianto; Kim, Hye Jin; Hwang, Woo Suk; Hossein, Mohammad Shamim; Kim, Joung Joo; Shin, Nam Shik; Kang, Sung Keun; Lee, Byeong Chun

    2007-01-01

    Over the world, canine species, including the gray wolf, have been gradually endangered or extinct. Many efforts have been made to recover and conserve these canids. The aim of this study was to produce the endangered gray wolf with somatic cell nuclear transfer (SCNT) for conservation. Adult ear fibroblasts from a female gray wolf (Canis lupus) were isolated and cultured in vitro as donor cells. Because of limitations in obtaining gray wolf matured oocytes, in vivo matured canine oocytes obtained by flushing the oviducts from the isthmus to the infundibulum were used. After removing the cumulus cells, the oocyte was enucleated, microinjected, fused with a donor cell, and activated. The reconstructed cloned wolf embryos were transferred into the oviducts of the naturally synchronized surrogate mothers. Two pregnancies were detected by ultrasonography at 23 days of gestation in recipient dogs. In each surrogate dog, two fetal sacs were confirmed by early pregnancy diagnosis at 23 days, but only two cloned wolves were delivered. The first cloned wolf was delivered by cesarean section on October 18, 2005, 60 days after embryo transfer. The second cloned wolf was delivered on October 26, 2005, at 61 days postembryo transfer. Microsatellite analysis was performed with genomic DNA from the donor wolf, the two cloned wolves, and the two surrogate female recipients to confirm the genetic identity of the cloned wolves. Analysis of 19 microsatellite loci confirmed that the cloned wolves were genetically identical to the donor wolf. In conclusion, we demonstrated live birth of two cloned gray wolves by nuclear transfer of wolf somatic cells into enucleated canine oocyte, indicating that SCNT is a practical approach for conserving endangered canids.

  12. Isolation of full-length putative rat lysophospholipase cDNA using improved methods for mRNA isolation and cDNA cloning

    International Nuclear Information System (INIS)

    Han, J.H.; Stratowa, C.; Rutter, W.J.

    1987-01-01

    The authors have cloned a full-length putative rat pancreatic lysophospholipase cDNA by an improved mRNA isolation method and cDNA cloning strategy using [ 32 P]-labelled nucleotides. These new methods allow the construction of a cDNA library from the adult rat pancreas in which the majority of recombinant clones contained complete sequences for the corresponding mRNAs. A previously recognized but unidentified long and relatively rare cDNA clone containing the entire sequence from the cap site at the 5' end to the poly(A) tail at the 3' end of the mRNA was isolated by single-step screening of the library. The size, amino acid composition, and the activity of the protein expressed in heterologous cells strongly suggest this mRNA codes for lysophospholipase

  13. Establishment and Analysis of Cancer Stem-Like and Non-Cancer Stem-Like Clone Cells from the Human Colon Cancer Cell Line SW480.

    Directory of Open Access Journals (Sweden)

    Akari Takaya

    Full Text Available Human cancer stem-like cells (CSCs/cancer-initiating cells (CICs can be isolated as side population (SP cells, aldehyde dehydrogenase high (ALDHhigh cells or cell surface marker-positive cells including CD44+ cells and CD133+ cells. CSCs/CICs and non-CSCs/CICs are unstable in in vitro culture, and CSCs/CICs can differentiate into non-CSCs/CICs and some non-CSCs/CICs can dedifferentiate into CSCs/CICs. Therefore, experiments using a large amount of CSCs/CICs are technically very difficult. In this study, we isolated single cell clones from SP cells and main population (MP cells derived from the human colon cancer cell line SW480. SP analysis revealed that SP clone cells had relatively high percentages of SP cells, whereas MP clone cells showed very few SP cells, and the phenotypes were sustainable for more than 2 months of in vitro culture. Xenograft transplantation revealed that SP clone cells have higher tumor-initiating ability than that of MP clone cells and SP clone cell showed higher chemo-resistance compared with MP clone cells. These results indicate that SP clone cells derived from SW480 cells are enriched with CSCs/CICs, whereas MP clone cells are pure non-CSCs/CICs. SP clone cells and MP clone cells are a very stable in vitro CSC/CIC-enriched and non-CSC/CIC model for further analysis.

  14. Establishment and Analysis of Cancer Stem-Like and Non-Cancer Stem-Like Clone Cells from the Human Colon Cancer Cell Line SW480.

    Science.gov (United States)

    Takaya, Akari; Hirohashi, Yoshihiko; Murai, Aiko; Morita, Rena; Saijo, Hiroshi; Yamamoto, Eri; Kubo, Terufumi; Nakatsugawa, Munehide; Kanaseki, Takayuki; Tsukahara, Tomohide; Tamura, Yasuaki; Takemasa, Ichiro; Kondo, Toru; Sato, Noriyuki; Torigoe, Toshihiko

    2016-01-01

    Human cancer stem-like cells (CSCs)/cancer-initiating cells (CICs) can be isolated as side population (SP) cells, aldehyde dehydrogenase high (ALDHhigh) cells or cell surface marker-positive cells including CD44+ cells and CD133+ cells. CSCs/CICs and non-CSCs/CICs are unstable in in vitro culture, and CSCs/CICs can differentiate into non-CSCs/CICs and some non-CSCs/CICs can dedifferentiate into CSCs/CICs. Therefore, experiments using a large amount of CSCs/CICs are technically very difficult. In this study, we isolated single cell clones from SP cells and main population (MP) cells derived from the human colon cancer cell line SW480. SP analysis revealed that SP clone cells had relatively high percentages of SP cells, whereas MP clone cells showed very few SP cells, and the phenotypes were sustainable for more than 2 months of in vitro culture. Xenograft transplantation revealed that SP clone cells have higher tumor-initiating ability than that of MP clone cells and SP clone cell showed higher chemo-resistance compared with MP clone cells. These results indicate that SP clone cells derived from SW480 cells are enriched with CSCs/CICs, whereas MP clone cells are pure non-CSCs/CICs. SP clone cells and MP clone cells are a very stable in vitro CSC/CIC-enriched and non-CSC/CIC model for further analysis.

  15. Isolation and partial characterization of peripheral blood CD4+ T cell clones expressing γδT cell receptors

    International Nuclear Information System (INIS)

    Kyoizumi, Seishi; Akiyama, Mitoshi; Hirai, Yuko; Kusunoki, Yoichiro.

    1990-06-01

    Rare T cell clones bearing both CD4 and T cell receptors (TCRγ and TCRδ) were obtained from human peripheral blood by cell sorting using anti-CD4 and anti-TCRδ1 antibodies. All the clones established were reactive with anti-TCRγδ1 antibody, whereas only about 20 % of the clones showed reactivity with anti-δTCS1 antibody. Unlike CD4 + T cells bearing TCRαβ, all the clones tested were lectin-dependent and showed CD3 antibody-redirected cytolytic activity. About 60 % exhibited natural killer cell-like activity. Immunoprecipitation analysis of TCRγδ showed that each clone expressed either a disulfide-linked or nondisulfide-linked heterodimer consisting of 37-44 kilodalton TCRγ and TCRδ chains. Southern blot analyses of TCRγ and TCRδ genes revealed some identical rearrangement patterns, suggesting the limited heterogeneity of CD4 + TCRγδ + T cells in peripheral blood. (author)

  16. Putative porcine embryonic stem cell lines derived from aggregated four-celled cloned embryos produced by oocyte bisection cloning.

    Science.gov (United States)

    Siriboon, Chawalit; Lin, Yu-Hsuan; Kere, Michel; Chen, Chun-Da; Chen, Lih-Ren; Chen, Chien-Hong; Tu, Ching-Fu; Lo, Neng-Wen; Ju, Jyh-Cherng

    2015-01-01

    We attempted to isolate ES cell lines using inner cell masses from high-quality cloned porcine blastocysts. After being seeded onto feeders, embryos had better (P cloned embryos (62.8, 42.6 and 12.8% vs. 76.2, 55.2 and 26.2%, respectively) compared to the non-aggregated group (41.6, 23.4 and 3.9%). Effects of feeder types (STO vs. MEF) and serum sources (FBS vs. KSR) on extraction of cloned embryo-derived porcine ES cells were examined. More (17.1%) ntES cell lines over Passage 3 were generated in the MEF/KSR group. However, ntES cells cultured in KSR-supplemented medium had a low proliferation rate with defective morphology, and eventually underwent differentiation or apoptosis subsequently. Approximately 26.1, 22.7 and 35.7% of primary colonies were formed after plating embryos in DMEM, DMEM/F12 and α-MEM media, respectively. Survival rates of ntES cells cultured in α-MEM, DMEM and DMEM/F12 were 16.7, 4.3 and 6.8%, respectively (P > 0.05). We further examined the beneficial effect of TSA treatment of 3× aggregated cloned embryos on establishment of ntES cell lines. Primary colony numbers and survival rates of ntES cells beyond passage 3 were higher (P cells, remaining undifferentiated over 25 passages, had alkaline phosphatase activity and expressed ES specific markers Oct4, Nanog, Sox2, and Rex01. Moreover, these ntES cells successfully differentiated into embryoid bodies (EBs) that expressed specific genes of all three germ layers after being cultured in LIF-free medium. In conclusion, we have successfully derived putative porcine ntES cells with high efficiency from quality cloned embryos produced by embryo aggregation, and optimized the ES cell culture system suitable for establishing and maintaining ntES cell lines in undifferentiated state.

  17. Transfer of experimental autoimmune thyroiditis with T cell clones

    International Nuclear Information System (INIS)

    Romball, C.G.; Weigle, W.O.

    1987-01-01

    We have investigated three T lymphocyte clones isolated from CBA/CaJ mice primed with mouse thyroid extract (MTE) in adjuvant. All three clones are L3T4+, Ig-, and Lyt2- and proliferate to MTE, mouse thyroglobulin (MTG) and rat thyroid extract. Clones A7 and B7 transfer thyroiditis to irradiated (475 rad) syngeneic mice, but not to normal recipients. The thyroid lesion induced by the B7 clone is characterized by the infiltration of both mononuclear and polymorphonuclear cells. The thyroiditis is transient in that lesions are apparent 7 and 14 days after transfer, but thyroids return to normal by day 21. Clone B7 showed helper activity for trinitrophenyl-keyhole limpet hemocyanin-primed B cells in vitro when stimulated with trinitrophenyl-MTG and also stimulated the production of anti-MTG antibody in recipient mice. Clone A7 induced thyroid lesions characterized by infiltration of the thyroid with mononuclear cells, with virtually no polymorphonuclear cell infiltration. This clone has shown no helper activity following stimulation with trinitrophenyl-MTG. The third clone (D2) proliferates to and shows helper activity to MTG, but fails to transfer thyroiditis to syngeneic, irradiated mice. On continuous culture, clone B7 lost its surface Thy. The loss of Thy appears unrelated to the ability to transfer thyroiditis since subclones of B7 with markedly different percentages of Thy+ cells transferred disease equally well

  18. Hope for restoration of dead valuable bulls through cloning using donor somatic cells isolated from cryopreserved semen.

    Science.gov (United States)

    Selokar, Naresh L; Saini, Monika; Palta, Prabhat; Chauhan, Manmohan S; Manik, Radheysham; Singla, Suresh K

    2014-01-01

    Somatic cells were isolated from cryopreserved semen of 4 buffalo bulls, 3 of which had died over 10 years earlier, and were established in culture. The cells expressed cytokeratin-18, keratin and vimentin indicating that they were of epithelial origin. The cells were used as nuclear donors for hand-made cloning for producing buffalo embryos. The blastocyst rate and quality, as indicated by apoptotic index, were comparable among embryos produced using cells obtained from fresh or frozen-thawed semen or those obtained from conventional cell sources such as skin. Examination of the epigenetic status revealed that the global level of H3K27me3 but not that of H3K9/14ac and H4K5ac differed significantly (Pcloned embryos from different bulls. The relative mRNA abundance of HDAC1, DNMT1, P53 and CASPASE 3 but not that of DNMT3a differed in cells and in cloned embryos. Following transfer of 24 cloned embryos produced from fresh semen-derived cells to 12 recipients, one calf weighing 55 kg, which is now 6 months of age and is normal, was born through normal parturition. Following transfer of 20 embryos produced from frozen-thawed semen-derived cells to 10 recipients, 2 became pregnant, one of which aborted in the first trimester; the calf born was severely underweight (17 kg), and died 12 h after birth. The ability of cells derived from fresh and frozen-thawed semen to produce live offspring confirms the ability of these cells to be reprogrammed. Our findings pave the way for restoration of highly precious progeny-tested bulls, which has immense economic importance, and can also be used for restoration of endangered species.

  19. Hope for Restoration of Dead Valuable Bulls through Cloning Using Donor Somatic Cells Isolated from Cryopreserved Semen

    Science.gov (United States)

    Selokar, Naresh L.; Saini, Monika; Palta, Prabhat; Chauhan, Manmohan S.; Manik, Radheysham; Singla, Suresh K.

    2014-01-01

    Somatic cells were isolated from cryopreserved semen of 4 buffalo bulls, 3 of which had died over 10 years earlier, and were established in culture. The cells expressed cytokeratin-18, keratin and vimentin indicating that they were of epithelial origin. The cells were used as nuclear donors for hand-made cloning for producing buffalo embryos. The blastocyst rate and quality, as indicated by apoptotic index, were comparable among embryos produced using cells obtained from fresh or frozen-thawed semen or those obtained from conventional cell sources such as skin. Examination of the epigenetic status revealed that the global level of H3K27me3 but not that of H3K9/14ac and H4K5ac differed significantly (Pcloned embryos from different bulls. The relative mRNA abundance of HDAC1, DNMT1, P53 and CASPASE 3 but not that of DNMT3a differed in cells and in cloned embryos. Following transfer of 24 cloned embryos produced from fresh semen-derived cells to 12 recipients, one calf weighing 55 kg, which is now 6 months of age and is normal, was born through normal parturition. Following transfer of 20 embryos produced from frozen-thawed semen-derived cells to 10 recipients, 2 became pregnant, one of which aborted in the first trimester; the calf born was severely underweight (17 kg), and died 12 h after birth. The ability of cells derived from fresh and frozen-thawed semen to produce live offspring confirms the ability of these cells to be reprogrammed. Our findings pave the way for restoration of highly precious progeny-tested bulls, which has immense economic importance, and can also be used for restoration of endangered species. PMID:24614586

  20. Cloning Endangered Felids by Interspecies Somatic Cell Nuclear Transfer.

    Science.gov (United States)

    Gómez, Martha C; Pope, C Earle

    2015-01-01

    In 2003, the first wild felid was produced by interspecies somatic cell nuclear transfer. Since then other wild felid clone offspring have been produced by using the same technique with minor modifications. This chapter describes detailed protocols used in our laboratory for (1) the isolation, culture, and preparation of fibroblast cells as donor nucleus, and (2) embryo reconstruction with domestic cat enucleated oocytes to produce cloned embryos that develop to the blastocyst stage in vitro and, after transfer into synchronized recipients, establish successful pregnancies.

  1. Establishment of primary bovine intestinal epithelial cell culture and clone method.

    Science.gov (United States)

    Zhan, Kang; Lin, Miao; Liu, Ming-Mei; Sui, Yang-Nan; Zhao, Guo-Qi

    2017-01-01

    The aim of this study was to establish bovine intestinal epithelial cell (BIEC) line and provide a novel clone cell method. Although various strategies of bovine cell culture and clone techniques have been reported, these methods remain not established. Here, we culture successfully primary BIECs and establish a novel clone cell method. Our result showed that BIECs could be successfully cultured and passaged about generation 5. These cellular aggregates and clusters were adherent loosely at day 2 of culture. Cell aggregates and clusters start to proliferate after approximately 4 d. The BIECs showed positive reaction against cytokeratin 18, E-cadherin, and characteristics of epithelial-like morphology. In addition, the fatty acid-binding proteins (FABPs), villin, and intestinal peptidase (IP) band were positive in BIECs. Our results suggest that the establishment of culturing and clone BIEC methods will apply to isolate and clone other primary cells. These BIECs could therefore contribute to the study of bovine intestinal nutrient absorption and regulation, immune regulation, and the pathogenesis of the bovine intestinal disease, which will provide intestinal cell model in vitro.

  2. Molecular cloning of transcripts induced by UV-radiation in rodent cells

    International Nuclear Information System (INIS)

    Fornace, A.J. Jr.; Mitchell, J.B.

    1987-01-01

    Several inducible DNA repair genes have been well characterized in bacteria. In eukaryotes including mammalian cells, there is increasing evidence that similar events may occur. Recently, the authors have shown that hybridization subtraction can be used to enrich for sequences induced only several fold by a particular cell treatment such as heat shock. Chinese hamster V79 cells were UV-irradiated with 17 Jm/sup -2/ and cDNA was synthesized from the polyadenylated (poly A) RNA. This ''UV'' cDNA was hybridized with a 3 fold excess of polyA RNA from unirradiated cells and the nonhybridizing cDNA was isolated. With this approach, UV-induced sequences were enriched over 20 fold. This enriched cDNA was cloned into a high copy number plasmid and a cDNA library was constructed. By RNA dot blot and northern analysis, 42 clones from this library were found to represent transcripts induced 3 to 25 fold by UV. The most common isolates were found to be metallothionein transcripts by DNA sequencing. The metallothionein transcripts were found to be induced 10 to 25 fold by UV with maximum induction at 4-8 h after 10 Jm/sup -2/. A similar approach was also used with a Chinese hamster ovary line which does not express metallothionein and multiple clones were isolated which represented transcripts induced 3-15 fold by UV. Except for the metallothionein clones, the other Chinese hamster cDNA clones have not been identified, but it is probable that the protein products of at least some of these transcripts play a role in the cellular response to UV damage

  3. A NEW CELL CLONE DERIVED FROM TRICHOPLUSIA NI TN5B1-4 CELLS

    Institute of Scientific and Technical Information of China (English)

    Jian-xiaoTian; Chang-youLi; Gui-lingZheng; Guo-xunLi; PingWang; Granados

    2004-01-01

    The characteristics of a cultured cell line do not always remain stable and may change upon continuous passage. Most continuous cell lines, even after cloning, possess several genotypes that are constantly changing. There are numerous selective and adaptive culture processes, in addition to genetic instability, that may improve phenotypic change in cell growth, virus susceptibility, gene expression, and production of virus. Similar detrimental effects of long term passaging of insect cells have also been reported for continuous cell lines, for example, Tn5B 1-4 cells, which are the most widely used for the baculovirus expression vector system (BEVS), provide superior production of recombinant proteins,however, this high productivity may be more evident in low passage cells. In this paper, we describe the isolation of a cell clone, Tn5B-40, from low passage Tn5B 1-4 cells. The growth characteristics,productions of virus, and high level of recombinant protein productions were determined. The results showed the susceptibility of both clone and Tn5B 1-4 cells to wild-type AcNPV was approximately the same rate with over 95% of infection; when the cloned cells were infected with recombinant baculoviruses expressing β-galactosidase and secreted alkaline phosphatase (SEAP), expression of the recombinant proteins from the cloned cells exceeded that from the parental Tn5B 1-4 cells.

  4. Molecular cloning of cellulase genes from indigenous bacterial isolates

    International Nuclear Information System (INIS)

    Jong Bor Chyan; Pauline Liew Woan Ying; Mat Rasol Awang

    2006-01-01

    Indigenous cellulolytic bacterial isolates having high activities in degrading carboxymethyl cellulose (CMC) were isolated from local environments. Identification of these isolates were performed by molecular techniques. By using polymerase chain reaction (PCR) techniques, PCR products encoding cellulase gene were amplified from the total genomic DNAs. Purified PCR product was successfully cloned and expressed in Escherichia coli host system. The complete nucleotide sequences of the cellulase genes determined. The analysis of amino acid sequences deduced from the genes indicated that the cloned DNA fragments show high homology to those of endoglucanase genes of family GH5. All cloned genes consist of an N-terminal signal peptide, a catalytic domain of family 5 glycosyl hydrolase and a cellulose-binding domain of family III. (Author)

  5. HIV-1 isolation from infected peripheral blood mononuclear cells.

    Science.gov (United States)

    Dispinseri, Stefania; Saba, Elisa; Vicenzi, Elisa; Kootstra, Neeltje A; Schuitemaker, Hanneke; Scarlatti, Gabriella

    2014-01-01

    Human immunodeficiency virus 1 (HIV-1) isolation from peripheral blood mononuclear cells (PBMCs) allows retrieval of replication-competent viral variants. In order to impose the smallest possible selective pressure on the viral isolates, isolation must be carried out in primary cultures of cells and not in tumor derived cell lines. The procedure involves culture of PBMCs from an infected patient with phytohemagglutinin (PHA)-stimulated PBMC from seronegative donors, which provide susceptible target cells for HIV replication. HIV can be isolated from the bulk population of PBMCs or after cloning of the cells to obtain viral biological clones. Viral production is determined with p24 antigen (Ag) detection assays or with reverse transcriptase (RT) activity assay. Once isolated, HIV-1 can be propagated by infecting PHA-stimulated PBMCs from healthy donors. Aliquots from culture with a high production of virus are stored for later use.

  6. Production of a Cloned Buffalo (Bubalus bubalis) Calf from Somatic Cells Isolated from Urine.

    Science.gov (United States)

    Madheshiya, Pankaj K; Sahare, Amol A; Jyotsana, Basanti; Singh, Karn P; Saini, Monika; Raja, Anuj K; Kaith, Sakshi; Singla, Suresh K; Chauhan, Manmohan S; Manik, Radhey S; Palta, Prabhat

    2015-06-01

    This study was aimed at isolation of cells from urine and skin on the ventral part of the tails of healthy adult female buffaloes (Bubalus bubalis), an area rarely exposed to solar radiation, establishment of the cells in culture, and their use as donor cells for production of buffalo embryos by handmade cloning (HMC). The blastocyst rate and total cell number of urine- and tail skin-derived embryos were similar to those of control embryos derived from ear skin cells; however, their apoptotic index was lower (pear skin-derived cells, whereas in blastocysts, it was higher (p<0.05) in urine- and tail skin-derived HMC blastocysts than that in IVF blastocysts. The expression level of CASPASE3, CASPASE9, P53, DNMT1, DNMT3a, OCT4, and NANOG, which was similar in HMC blastocysts of three the groups, was lower (p<0.05) than that in IVF blastocysts, whereas that of HDAC1 was similar among the four groups. Following transfer of urine-derived embryos (n=10) to five recipients (two embryos/recipient), one of the recipients delivered a normal calf that is now 5 weeks old.

  7. Antigen-specific T8+ human clone of cells with a nonspecific augmenting function on the T4 cell-B cell helper interaction

    International Nuclear Information System (INIS)

    Brines, R.D.; Sia, D.Y.; Lehner, T.

    1987-01-01

    The authors isolated a T8 + T3 + Ia + clone of cells from the peripheral blood mononuclear cells of a healthy subject. The clone was expanded and maintained with autologous feed cells, interleukin 2, and a streptococcal antigen. The T8 + clone of cells responded specifically to the streptococcal antigen, in the absence of accessory cells,and released a soluble factor. Both the cloned cells and the corresponding soluble factor expressed augmenting helper but not suppressor activity. The augmenting helper activity for B cell antibody synthesis was demonstrable only in the presence of autologous T 4 cells. Radioimmunoassay was used to measure antibodies. Although stimulation of the T8 + cloned cells was antigen-specific, the resulting soluble factor elicited nonspecific antibody synthesis in the presence of T4 and B cells. The T8 + cloned cell-derived factor was adsorbed by B cells but not by T4 cells. Preliminary studies suggest that the factor has the properties of a B cell growth factor. They suggest that the T8 + population consists of functionally heterogeneous cell subsets, some that have suppressor function and others that augment the T4 + helper-inducer activity in B cell antibody synthesis

  8. Clonal analysis of T-cell responses to herpes simplex virus: isolation, characterization and antiviral properties of an antigen-specific helper T-cell clone.

    Science.gov (United States)

    Leung, K N; Nash, A A; Sia, D Y; Wildy, P

    1984-12-01

    A herpes simplex virus (HSV)-specific long-term T-cell clone has been established from the draining lymph node cells of BALB/c mice; the cells required repeated in vitro restimulation with UV-irradiated virus. The established T-cell clone expresses the Thy-1 and Lyt-1+2,3- surface antigens. For optimal proliferation of the cloned cells, both the presence of specific antigen and an exogenous source of T-cell growth factor are required. The proliferative response of the cloned T cells was found to be virus-specific but it did not distinguish between HSV-1 and HSV-2. Adoptive cell transfer of the cloned T cells helped primed B cells to produce anti-herpes antibodies: the response was antigen-specific and cell dose-dependent. The clone failed to produce a significant DTH reaction in vivo, but did produce high levels of macrophage-activating factor. Furthermore, the T-cell clone could protect from HSV infection, as measured by a reduction in local virus growth, and by enhanced survival following the challenge of mice with a lethal dose of virus. The mechanism(s) whereby this clone protects in vivo is discussed.

  9. Heterogeneity in induced thermal resistance of rat tumor cell clones

    International Nuclear Information System (INIS)

    Tomasovic, S.P.; Rosenblatt, P.L.; Heitzman, D.

    1983-01-01

    Four 13762NF rat mammary adenocarcinoma clones were examined for their survival response to heating under conditions that induced transient thermal resistance (thermotolerance). Clones MTC and MTF7 were isolated from the subcutaneous locally growing tumor, whereas clones MTLn2 and MTLn3 were derived from spontaneous lung metastases. There was heterogeneity among these clones in thermotolerance induced by either fractionated 45 0 C or continuous 42 0 C heating, but the order of sensitivity was not necessarily the same. The clones developed thermal resistance at different rates and to different degrees within the same time intervals. There was heterogeneity between clones isolated from within either the primary site or metastatic lesions. However, clones derived from metastatic foci did not intrinsically acquire more or less thermotolerance to fractionated 45 0 C or continuous 42 0 C heating than did clones from the primary tumor. Further, there was no apparent relationship between any phenotypic properties that conferred more or less thermotolerance in vitro and any phenotypic properties that conferred enhanced metastatic success of these same clones by spontaneous (subcutaneous) or experimental (intravenous) routes in vivo. These tumor clones also differ in their karyotype, metastatic potential, cell surface features, sensitivity to x-irradiation and drugs, and ability to repair sublethal radiation damage. These results provide further credence to the concept that inherent heterogeneity within tumors may be as important in therapeutic success as other known modifiers of outcome such as site and treatment heterogeneity

  10. Complementation of radiation-sensitive Ataxia telangiectasia cells after transfection of cDNA expression libraries and cosmid clones from wildtype cells

    International Nuclear Information System (INIS)

    Fritz, E.

    1994-06-01

    In this Ph.D.-thesis, phenotypic complementation of AT-cells (AT5BIVA) by transfection of cDNA-expression-libraries was adressed: After stable transfection of cDNA-expression-libraries G418 resistant clones were selected for enhanced radioresistance by a fractionated X-ray selection. One surviving transfectant clone (clone 514) exhibited enhanced radiation resistance in dose-response experiments and further X-ray selections. Cell cycle analysis revealed complementation of untreated and irradiated 514-cells in cell cycle progression. The rate of DNA synthesis, however, is not diminished after irradiation but shows the reverse effect. A transfected cDNA-fragment (AT500-cDNA) was isolated from the genomic DNA of 514-cells and proved to be an unknown DNA sequence. A homologous sequence could be detected in genomic DNA from human cell lines, but not in DNA from other species. The cDNA-sequence could be localized to human chromosome 11. In human cells the cDNA sequence is part of two large mRNAs. 4 different cosmid clones containing high molecular genomic DNA from normal human cells could be isolated from a library, each hybridizing to the AT500-cDNA. After stable transfection into AT-cells, one cosmid-clone was able to confer enhanced radiation resistance both in X-ray selections and dose-response experiments. The results indicate that the cloned cDNA-fragment is based on an unknown gene from human chromosome 11 which partially complements the radiosensitivity and the defective cell cycle progression in AT5BIVA cells. (orig.) [de

  11. In vivo localization of cloned IL-2-dependent T cells

    International Nuclear Information System (INIS)

    Carroll, A.M.; Palladino, M.A.; Oettgen, H.; De Sousa, M.

    1983-01-01

    The quantitative organ distribution and tissue microenvironment positioning of radioisotopically labeled cloned T cells were characterized. Intravenous (iv) injection of 51chromium ( 51 Cr)-labeled, long-term cultured cloned T-helper cells and cells from several cloned cytolytic T-lymphocyte lines (CTLL) resulted in poor localization of these cells in recipient lymphoid tissues, similar to results reported for activated lymphoblastoid cells. Simultaneous administration of interleukin 2 (IL-2) with labeled cells resulted in enhanced recovery from recipient spleen. By the intraperitoneal (ip) injection route, overall percentage recovery of injected radioactivity was lower than by the iv route, but significant localization to lymph nodes occurred. Examination of autoradiographs of tissue sections from recipients of [ 3 H]adenosine-labeled cells showed most label associated with intact, isolated cells in the liver, lungs, spleen, and small intestine. By 24 hr after iv injection, labeled cells in spleen sections were distributed to both nonlymphoid and T- and B-lymphoid areas. These findings suggest that poor localization of these cells to recipient lymphoid tissue is due both to intrinsic characteristics of cultured lymphocytes and to the possible reduced viability of IL-2-dependent cells in vivo

  12. Establishment and characterization of canine parvovirus-specific murine CD4+ T cell clones and their use for the delineation of T cell epitopes.

    NARCIS (Netherlands)

    G.F. Rimmelzwaan (Guus); R.W.J. van der Heijden (Roger); E.J. Tijhaar (Edwin); M.C.M. Poelen (Martien); J. Carlson; A.D.M.E. Osterhaus (Albert); F.G.C.M. Uytdehaag (Fons)

    1990-01-01

    textabstractCanine parvovirus (CPV)-specific T cell clones were generated by culturing lymph node cells from CPV-immunized BALB/c mice at limiting dilutions in the presence of CPV antigen and interleukin-2 (IL-2). All isolated T cell clones exhibited the cell surface phenotype Thy1+, CD4+, CD8- and

  13. Isolation, cloning and molecular characterization of a thermotolerant ...

    African Journals Online (AJOL)

    Isolation, cloning and molecular characterization of a thermotolerant xylanase from Streptomyces sp. THW31. Thayat Sriyapai, Peechapack Somyoonsap, Supatra Areekit, Paisarn Khawsak, Arda Pakpitcharoen, Kosum Chansiri ...

  14. Isolation and characterization of cDNA clones for carrot extensin and a proline-rich 33-kDa protein

    International Nuclear Information System (INIS)

    Chen, J.; Varner, J.E.

    1985-01-01

    Extensins are hydroxyproline-rich glycoproteins associated with most dicotyledonous plant cell walls. To isolate cDNA clones encoding extensin, the authors started by isolating poly(A) + RNA from carrot root tissue, and then translating the RNA in vitro, in the presence of tritiated leucine or proline. A 33-kDa peptide was identified in the translation products as a putative extensin precursor. From a cDNA library constructed with poly(A) + RNA from wounded carrots, one cDNA clone (pDC5) was identified that specifically hybridized to poly(A) + RNA encoding this 33-kDa peptide. They isolated three cDNA clones (pDC11, pDC12, and pDC16) from another cDNA library using pCD5 as a probe. DNA sequence data, RNA hybridization analysis, and hybrid released in vitro translation indicate that the cDNA clones pDC11 encodes extensin and that cDNA clones pDC12 and pDC16 encode the 33-kDa peptide, which as yet has an unknown identity and function. The assumption that the 33-kDa peptide was an extensin precursor was invalid. RNA hybridization analysis showed that RNA encoded by both clone types is accumulated upon wounding

  15. Establishment of bipotent progenitor cell clone from rat skeletal muscle.

    Science.gov (United States)

    Murakami, Yousuke; Yada, Erica; Nakano, Shin-ichi; Miyagoe-Suzuki, Yuko; Hosoyama, Tohru; Matsuwaki, Takashi; Yamanouchi, Keitaro; Nishihara, Masugi

    2011-12-01

    The present study describes the isolation, cloning and characterization of adipogenic progenitor cells from rat skeletal muscle. Among the obtained 10 clones, the most highly adipogenic progenitor, 2G11 cells, were further characterized. In addition to their adipogenicity, 2G11 cells retain myogenic potential as revealed by formation of multinucleated myotubes when co-cultured with myoblasts. 2G11 cells were resistant to an inhibitory effect of basic fibroblast growth factor on adipogenesis, while adipogenesis of widely used preadipogenic cell line, 3T3-L1 cells, was suppressed almost completely by the same treatment. In vivo transplantation experiments revealed that 2G11 cells are able to possess both adipogenicity and myogenicity in vivo. These results indicate the presence of bipotent progenitor cells in rat skeletal muscle, and suggest that such cells may contribute to ectopic fat formation in skeletal muscle. © 2011 The Authors. Animal Science Journal © 2011 Japanese Society of Animal Science.

  16. Isolation and Cloning of mercuric reductase gene (merA from mercury-resistant bacteria

    Directory of Open Access Journals (Sweden)

    Parisa Khoshniyat

    2018-03-01

    Full Text Available Introduction: Some of the bacteria having merA gene coding mineral mercury reducing enzyme, has genetic potential of Hg removing via reduction of mineral mercury and transformation of that to gas form and finally bioremediation of polluted area. The aim of this study is the isolation of merA gene from resistance bacteria and cloning of that into suitable expression vector and then the environmental bioremediation by the transformation of bacteria with this vector. Materials and methods: A number of bacteria were collected in contaminated areas with mercury in order to isolate merA genes. Polymerase chain reaction had done on the four bacterial genomes including Klebsiella pneumoniae, Pseudomonas aeruginosa, Serratia marcescens and Escherichia coli using the specific primers in order to detect merA gene. For cloning, the primers containing restriction enzyme sites are used, merA gene was isolated and amplified. The amplified fragments were cloned in the expression vector pET21a+ and via heat shock method were transformed into E. coli TOP10 competent cell. For clustering of genes, Mega software version 4 was used and bioanformatic studies were achieved for predicted enzyme. Results: merA gene with 1686 bp in length was isolated from K pneumoniae and E. coli. Recombinant vectors in transgenic bacteria were confirmed by various methods and finally were confirmed by sequencing. The result of clustering these genes with existence genes in NCBI showed high similarity. Discussion and conclusion: The existence of merA gene in bacteria that adapted to Hg pollution area is because of resistance, so with cloning this gene into suitable expression vector and transformation of susceptible bacteria with this vector ability of resistance to Hg in bacteria for bioremediation could be given.

  17. Specific single-cell isolation and genomic amplification of uncultured microorganisms

    DEFF Research Database (Denmark)

    Kvist, Thomas; Ahring, Birgitte Kiær; Lasken, R.S.

    2007-01-01

    We in this study describe a new method for genomic studies of individual uncultured prokaryotic organisms, which was used for the isolation and partial genome sequencing of a soil archaeon. The diversity of Archaea in a soil sample was mapped by generating a clone library using group-specific pri......We in this study describe a new method for genomic studies of individual uncultured prokaryotic organisms, which was used for the isolation and partial genome sequencing of a soil archaeon. The diversity of Archaea in a soil sample was mapped by generating a clone library using group......-specific primers in combination with a terminal restriction fragment length polymorphism profile. Intact cells were extracted from the environmental sample, and fluorescent in situ hybridization probing with Cy3-labeled probes designed from the clone library was subsequently used to detect the organisms...... of interest. Single cells with a bright fluorescent signal were isolated using a micromanipulator and the genome of the single isolated cells served as a template for multiple displacement amplification (MDA) using the Phi29 DNA polymerase. The generated MDA product was afterwards used for 16S rRNA gene...

  18. Isolation and characterization of human cDNA clones encoding the α and the α' subunits of casein kinase II

    International Nuclear Information System (INIS)

    Lozeman, F.J.; Litchfield, D.W.; Piening, C.; Takio, Koji; Walsh, K.A.; Krebs, E.G.

    1990-01-01

    Casein kinase II is a widely distributed protein serine/threonine kinase. The holoenzyme appears to be a tetramer, containing two α or α' subunits (or one of each) and two β subunits. Complementary DNA clones encoding the subunits of casein kinase II were isolated from a human T-cell λgt 10 library using cDNA clones isolated from Drosophila melanogasten. One of the human cDNA clones (hT4.1) was 2.2 kb long, including a coding region of 1176 bp preceded by 156 bp (5' untranslated region) and followed by 871 bp (3' untranslated region). The hT4.1 close was nearly identical in size and sequence with a cDNA clone from HepG2 human hepatoma cultured cells. Another of the human T-cell cDNA clones (hT9.1) was 1.8 kb long, containing a coding region of 1053 bp preceded by 171 by (5' untranslated region) and followed by 550 bp (3' untranslated region). Amino acid sequences deduced from these two cDNA clones were about 85% identical. Most of the difference between the two encoded polypeptides was in the carboxy-terminal region, but heterogeneity was distributed throughout the molecules. Partial amino acid sequence was determined in a mixture of α and α' subunits from bovine lung casein kinase II. The bovine sequences aligned with the 2 human cDNA-encoded polypeptides with only 2 discrepancies out of 535 amino acid positions. This confirmed that the two human T-cell cDNA clones encoded the α and α' subunits of casein kinase II. These studies show that there are two distinct catalytic subunits for casein II (α and α') and that the sequence of these subunits is largely conserved between the bovine and the human

  19. Use of high throughput qPCR screening to rapidly clone low frequency tumour specific T-cells from peripheral blood for adoptive immunotherapy

    Directory of Open Access Journals (Sweden)

    Serrano Oscar K

    2008-10-01

    Full Text Available Abstract Background The adoptive transfer of autologous tumor reactive lymphocytes can mediate significant tumor regression in some patients with refractory metastatic cancer. However, a significant obstacle for this promising therapy has been the availability of highly efficient methods to rapidly isolate and expand a variety of potentially rare tumor reactive lymphocytes from the natural repertoire of cancer patients. Methods We developed a novel in vitro T cell cloning methodology using high throughput quantitative RT-PCR (qPCR assay as a rapid functional screen to detect and facilitate the limiting dilution cloning of a variety of low frequency T cells from bulk PBMC. In preclinical studies, this strategy was applied to the isolation and expansion of gp100 specific CD8+ T cell clones from the peripheral blood of melanoma patients. Results In optimization studies, the qPCR assay could detect the reactivity of 1 antigen specific T cell in 100,000 background cells. When applied to short term sensitized PBMC microcultures, this assay could detect T cell reactivity against a variety of known melanoma tumor epitopes. This screening was combined with early limiting dilution cloning to rapidly isolate gp100154–162 reactive CD8+ T cell clones. These clones were highly avid against peptide pulsed targets and melanoma tumor lines. They had an effector memory phenotype and showed significant proliferative capacity to reach cell numbers appropriate for adoptive transfer trials (~1010 cells. Conclusion This report describes a novel high efficiency strategy to clone tumor reactive T cells from peripheral blood for use in adoptive immunotherapy.

  20. Heterogeneity of functional properties of Clone 66 murine breast cancer cells expressing various stem cell phenotypes.

    Science.gov (United States)

    Mukhopadhyay, Partha; Farrell, Tracy; Sharma, Gayatri; McGuire, Timothy R; O'Kane, Barbara; Sharp, J Graham

    2013-01-01

    Breast cancer grows, metastasizes and relapses from rare, therapy resistant cells with a stem cell phenotype (cancer stem cells/CSCs). However, there is a lack of studies comparing the functions of CSCs isolated using different phenotypes in order to determine if CSCs are homogeneous or heterogeneous. Cells with various stem cell phenotypes were isolated by sorting from Clone 66 murine breast cancer cells that grow orthotopically in immune intact syngeneic mice. These populations were compared by in vitro functional assays for proliferation, growth, sphere and colony formation; and in vivo limiting dilution analysis of tumorigenesis. The proportion of cells expressing CD44(high)CD24(low/neg), side population (SP) cells, ALDH1(+), CD49f(high), CD133(high), and CD34(high) differed, suggesting heterogeneity. Differences in frequency and size of tumor spheres from these populations were observed. Higher rates of proliferation of non-SP, ALDH1(+), CD34(low), and CD49f(high) suggested properties of transit amplifying cells. Colony formation was higher from ALDH1(-) and non-SP cells than ALDH1(+) and SP cells suggesting a progenitor phenotype. The frequency of clonal colonies that grew in agar varied and was differentially altered by the presence of Matrigel™. In vivo, fewer cells with a stem cell phenotype were needed for tumor formation than "non-stem" cells. Fewer SP cells were needed to form tumors than ALDH1(+) cells suggesting further heterogeneities of cells with stem phenotypes. Different levels of cytokines/chemokines were produced by Clone 66 with RANTES being the highest. Whether the heterogeneity reflects soluble factor production remains to be determined. These data demonstrate that Clone 66 murine breast cancer cells that express stem cell phenotypes are heterogeneous and exhibit different functional properties, and this may also be the case for human breast cancer stem cells.

  1. [Nuclear transfer and therapeutic cloning].

    Science.gov (United States)

    Xu, Xiao-Ming; Lei, An-Min; Hua, Jin-Lian; Dou, Zhong-Ying

    2005-03-01

    Nuclear transfer and therapeutic cloning have widespread and attractive prospects in animal agriculture and biomedical applications. We reviewed that the quality of oocytes and nuclear reprogramming of somatic donor cells were the main reasons of the common abnormalities in cloned animals and the low efficiency of cloning and showed the problems and outlets in therapeutic cloning, such as some basic problems in nuclear transfer affected clinical applications of therapeutic cloning. Study on isolation and culture of nuclear transfer embryonic stem (ntES) cells and specific differentiation of ntES cells into important functional cells should be emphasized and could enhance the efficiency. Adult stem cells could help to cure some great diseases, but could not replace therapeutic cloning. Ethics also impeded the development of therapeutic cloning. It is necessary to improve many techniques and reinforce the research of some basic theories, then somatic nuclear transfer and therapeutic cloning may apply to agriculture reproduction and benefit to human life better.

  2. Plasticity of marrow mesenchymal stem cells from human first-trimester fetus: from single-cell clone to neuronal differentiation.

    Science.gov (United States)

    Zhang, Yihua; Shen, Wenzheng; Sun, Bingjie; Lv, Changrong; Dou, Zhongying

    2011-02-01

    Recent results have shown that bone marrow mesenchymal stem cells (BMSCs) from human first-trimester abortus (hfBMSCs) are closer to embryonic stem cells and perform greater telomerase activity and faster propagation than mid- and late-prophase fetal and adult BMSCs. However, no research has been done on the plasticity of hfBMSCs into neuronal cells using single-cell cloned strains without cell contamination. In this study, we isolated five single cells from hfBMSCs and obtained five single-cell cloned strains, and investigated their biological property and neuronal differentiation potential. We found that four of the five strains showed similar expression profile of surface antigen markers to hfBMSCs, and most of them differentiated into neuron-like cells expressing Nestin, Pax6, Sox1, β-III Tubulin, NF-L, and NSE under induction. One strain showed different expression profile of surface antigen markers from the four strains and hfBMSCs, and did not differentiate toward neuronal cells. We demonstrated for the first time that some of single-cell cloned strains from hfBMSCs can differentiate into nerve tissue-like cell clusters under induction in vitro, and that the plasticity of each single-cell cloned strain into neuronal cells is different.

  3. Rabies virus cross-reactive murine T cell clones: analysis of helper and delayed-type hypersensitivity function.

    NARCIS (Netherlands)

    H. Bunschoten; B. Dietzschold; I.J.Th.M. Claassen (Ivo); R. Klapmuts; F. UytdeHaag; A.D.M.E. Osterhaus (Albert)

    1990-01-01

    textabstractThree T cell clones derived from rabies virus-immunized BALB/c mice were analysed for specificity and function. The clones proved to be broadly cross-reactive by responding to different rabies virus isolates (PM, ERA, CVS, HEP) and other representatives of the genus Lyssavirus, like the

  4. Autoreactive T cell clones specific for class I and class II HLA antigens isolated from a human chimera

    NARCIS (Netherlands)

    Roncarolo, M. G.; Yssel, H.; Touraine, J. L.; Betuel, H.; de Vries, J. E.; Spits, H.

    1988-01-01

    T cell clones of donor origin that specifically react with recipient cells were obtained from a SCID patient successfully reconstituted by allogeneic fetal liver and thymus transplantation performed 10 yr ago. The majority of these clones displayed both cytotoxic and proliferative responses towards

  5. Generation of an infectious clone of VR-2332, a highly virulent North American type isolate of porcine reproductive and respiratory syndrome virus

    DEFF Research Database (Denmark)

    Nielsen, H.S.; Liu, G.; Nielsen, Jens

    2003-01-01

    A full-length cDNA clone of the prototypical North American porcine reproductive and respiratory syndrome virus (PRRSV) isolate VR-2332 was assembled in the plasmid vector pOK(12). To rescue infectious virus, capped RNA was transcribed in vitro from the pOK(12) clone and transfected into BHK-21C...... cells. The supernatant from transfected monolayers were serially passaged on Marc-145 cells and porcine pulmonary alveolar macrophages. Infectious PRRSV was recovered on Marc-145 cells as well as porcine pulmonary macrophages; thus, the cloned virus exhibited the same cell tropism as the parental VR......-2332 strain. However, the cloned virus was clearly distinguishable from the parental VR-2332 strain by an engineered marker, a BstZ171 restriction site. The full-length cDNA clone had 11 nucleotide changes, 2 of which affected coding, compared to the parental VR-2332 strain. Additionally...

  6. Cloning mice and ES cells by nuclear transfer from somatic stem cells and fully differentiated cells.

    Science.gov (United States)

    Wang, Zhongde

    2011-01-01

    Cloning animals by nuclear transfer (NT) has been successful in several mammalian species. In addition to cloning live animals (reproductive cloning), this technique has also been used in several species to establish cloned embryonic stem (ntES) cell lines from somatic cells. It is the latter application of this technique that has been heralded as being the potential means to produce isogenic embryonic stem cells from patients for cell therapy (therapeutic cloning). These two types of cloning differ only in the steps after cloned embryos are produced: for reproductive cloning the cloned embryos are transferred to surrogate mothers to allow them to develop to full term and for therapeutic cloning the cloned embryos are used to derive ntES cells. In this chapter, a detailed NT protocol in mouse by using somatic stem cells (neuron and skin stem cells) and fully differentiated somatic cells (cumulus cells and fibroblast cells) as nuclear donors is described.

  7. Optimization of cell line development in the GS-CHO expression system using a high-throughput, single cell-based clone selection system.

    Science.gov (United States)

    Nakamura, Tsuyoshi; Omasa, Takeshi

    2015-09-01

    Therapeutic antibodies are commonly produced by high-expressing, clonal and recombinant Chinese hamster ovary (CHO) cell lines. Currently, CHO cells dominate as a commercial production host because of their ease of use, established regulatory track record, and safety profile. CHO-K1SV is a suspension, protein-free-adapted CHO-K1-derived cell line employing the glutamine synthetase (GS) gene expression system (GS-CHO expression system). The selection of high-producing mammalian cell lines is a crucial step in process development for the production of therapeutic antibodies. In general, cloning by the limiting dilution method is used to isolate high-producing monoclonal CHO cells. However, the limiting dilution method is time consuming and has a low probability of monoclonality. To minimize the duration and increase the probability of obtaining high-producing clones with high monoclonality, an automated single cell-based clone selector, the ClonePix FL system, is available. In this study, we applied the high-throughput ClonePix FL system for cell line development using CHO-K1SV cells and investigated efficient conditions for single cell-based clone selection. CHO-K1SV cell growth at the pre-picking stage was improved by optimizing the formulation of semi-solid medium. The efficiency of picking and cell growth at the post-picking stage was improved by optimization of the plating time without decreasing the diversity of clones. The conditions for selection, including the medium formulation, were the most important factors for the single cell-based clone selection system to construct a high-producing CHO cell line. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  8. Simultaneous cloning and expression of two cellulase genes from Bacillus subtilis newly isolated from Golden Takin (Budorcas taxicolor Bedfordi)

    International Nuclear Information System (INIS)

    Li, Wang; Huan, Xiajuan; Zhou, Ying; Ma, Qingyi; Chen, Yulin

    2009-01-01

    A bacterial strain with high cellulase activity was isolated of feces sample of Golden Takin (Budorcas taxicolor Bedfordi). The bacterium was classified and designated Bacillus subtilis LN by morphological and 16SrDNA gene sequence analysis. Two putative cellulase genes, CelL15 and CelL73, were simultaneously cloned from the isolated strain by PCR. The putative gene CelL15 consisted of an open reading frame (ORF) of 1470 nucleotides and encoded a protein of 490 amino acids with a molecular weight of 54 kDa. The CelL73 gene consisted of an open reading frame (ORF) of 741 nucleotides and encoded a protein of 247 amino acids with a molecular weight of 27 kDa. Both genes were purified and cloned into pET-28a for expression in Escherichia coli BL21 (DE3). The ability of E. coli to degrade cellulose was enhanced when the two recombinants were cultured together.

  9. Differentiated cells are more efficient than adult stem cells for cloning by somatic cell nuclear transfer.

    Science.gov (United States)

    Sung, Li-Ying; Gao, Shaorong; Shen, Hongmei; Yu, Hui; Song, Yifang; Smith, Sadie L; Chang, Ching-Chien; Inoue, Kimiko; Kuo, Lynn; Lian, Jin; Li, Ao; Tian, X Cindy; Tuck, David P; Weissman, Sherman M; Yang, Xiangzhong; Cheng, Tao

    2006-11-01

    Since the creation of Dolly via somatic cell nuclear transfer (SCNT), more than a dozen species of mammals have been cloned using this technology. One hypothesis for the limited success of cloning via SCNT (1%-5%) is that the clones are likely to be derived from adult stem cells. Support for this hypothesis comes from the findings that the reproductive cloning efficiency for embryonic stem cells is five to ten times higher than that for somatic cells as donors and that cloned pups cannot be produced directly from cloned embryos derived from differentiated B and T cells or neuronal cells. The question remains as to whether SCNT-derived animal clones can be derived from truly differentiated somatic cells. We tested this hypothesis with mouse hematopoietic cells at different differentiation stages: hematopoietic stem cells, progenitor cells and granulocytes. We found that cloning efficiency increases over the differentiation hierarchy, and terminally differentiated postmitotic granulocytes yield cloned pups with the greatest cloning efficiency.

  10. In vitro stemness characterization of radio-resistant clones isolated from a medulloblastoma cell line ONS-76

    International Nuclear Information System (INIS)

    Sun, Lue; Suzuki, Kenshi; Gerelchuluun, Ariungerel; Hong, Zhengshan; Moritake, Takashi; Zenkoh, Junko; Tsuboi, Koji; Zheng, Yun-Wen; Taniguchi, Hideki

    2013-01-01

    One-third of patients with medulloblastoma die due to recurrence after various treatments including radiotherapy. Although it has been postulated that cancer stem-like cells are radio-resistant and play an important role in tumor recurrence, the 'stemness' of medulloblastoma cells surviving irradiation has not yet been elucidated. Using a medulloblastoma cell line ONS-76, cells that survived gamma irradiation were investigated on their 'stemness' in vitro. From 10 500 cells, 20 radio-resistant clones were selected after gamma ray irradiation (5 Gy x two fractions) using the replica micro-well technique. These 20 resistant clones were screened for CD133 positivity by flow cytometry followed by side population assay, tumor sphere formation assay and clonogenic survival assay. Results revealed CD133 fractions were significantly elevated in three clones, which also exhibited significantly increased levels of tumor sphere formation ability and side population fraction. Clonogenic survival assay demonstrated that their radio-resistance was significantly higher than the parental ONS-76. This may support the hypothesis that a small number of cancer stem-like cells (CSCs) are the main culprits in local recurrence after radiotherapy, and disruption of the resistance mechanism of these CSCs is a critical future issue in improving the outcome of patients with medulloblastoma. (author)

  11. Production of cloned mice and ES cells from adult somatic cells by nuclear transfer: how to improve cloning efficiency?

    Science.gov (United States)

    Wakayama, Teruhiko

    2007-02-01

    Although it has now been 10 years since the first cloned mammals were generated from somatic cells using nuclear transfer (NT), most cloned embryos usually undergo developmental arrest prior to or soon after implantation, and the success rate for producing live offspring by cloning remains below 5%. The low success rate is believed to be associated with epigenetic errors, including abnormal DNA hypermethylation, but the mechanism of "reprogramming" is unclear. We have been able to develop a stable NT method in the mouse in which donor nuclei are directly injected into the oocyte using a piezo-actuated micromanipulator. Especially in the mouse, only a few laboratories can make clones from adult somatic cells, and cloned mice are never successfully produced from most mouse strains. However, this technique promises to be an important tool for future research in basic biology. For example, NT can be used to generate embryonic stem (NT-ES) cell lines from a patient's own somatic cells. We have shown that NT-ES cells are equivalent to ES cells derived from fertilized embryos and that they can be generated relatively easily from a variety of mouse genotypes and cell types of both sexes, even though it may be more difficult to generate clones directly. In general, NT-ES cell techniques are expected to be applied to regenerative medicine; however, this technique can also be applied to the preservation of genetic resources of mouse strain instead of embryos, oocytes and spermatozoa. This review describes how to improve cloning efficiency and NT-ES cell establishment and further applications.

  12. BIOLOGICAL CLONING OF A BOVINE CORONAVIRUS ISOLATE

    OpenAIRE

    Betancourt, A; Rodríguez, Edisleidy; Relova, Damarys; Barrera, Maritza

    2008-01-01

    Con el objetivo de obtener un aislado de Coronavirus bovino clonado biológicamente se adaptó el aislado VB73/04 a la multiplicación en la línea celular MDBK. Este aislado indujo la formación de placas, las cuales resultaron homogéneas después del clonaje biológico. La población viral obtenida fue identificada como Coronavirus bovino por RT-PCR y Seroneutralización. In order to obtain a biologically cloned bovine coronavirus isolate, the isolate VB73/04 was adapted to multiplication in MDBK...

  13. Cloning the Gravity and Shear Stress Related Genes from MG-63 Cells by Subtracting Hybridization

    Science.gov (United States)

    Zhang, Shu; Dai, Zhong-quan; Wang, Bing; Cao, Xin-sheng; Li, Ying-hui; Sun, Xi-qing

    2008-06-01

    Background The purpose of the present study was to clone the gravity and shear stress related genes from osteoblast-like human osteosarcoma MG-63 cells by subtractive hybridization. Method MG-63 cells were divided into two groups (1G group and simulated microgravity group). After cultured for 60 h in two different gravitational environments, two groups of MG-63 cells were treated with 1.5Pa fluid shear stress (FSS) for 60 min, respectively. The total RNA in cells was isolated. The gravity and shear stress related genes were cloned by subtractive hybridization. Result 200 clones were gained. 30 positive clones were selected using PCR method based on the primers of vector and sequenced. The obtained sequences were analyzed by blast. changes of 17 sequences were confirmed by RT-PCR and these genes are related to cell proliferation, cell differentiation, protein synthesis, signal transduction and apoptosis. 5 unknown genes related to gravity and shear stress were found. Conclusion In this part of our study, our result indicates that simulated microgravity may change the activities of MG-63 cells by inducing the functional alterations of specific genes.

  14. Cloning endangered gray wolves (Canis lupus) from somatic cells collected postmortem.

    Science.gov (United States)

    Oh, H J; Kim, M K; Jang, G; Kim, H J; Hong, S G; Park, J E; Park, K; Park, C; Sohn, S H; Kim, D Y; Shin, N S; Lee, B C

    2008-09-01

    The objective of the present study was to investigate whether nuclear transfer of postmortem wolf somatic cells into enucleated dog oocytes, is a feasible method to produce a cloned wolf. In vivo-matured oocytes (from domestic dogs) were enucleated and fused with somatic cells derived from culture of tissue obtained from a male gray wolf 6h after death. The reconstructed embryos were activated and transferred into the oviducts of naturally synchronous domestic bitches. Overall, 372 reconstructed embryos were transferred to 17 recipient dogs; four recipients (23.5%) were confirmed pregnant (ultrasonographically) 23-25 d after embryo transfer. One recipient spontaneously delivered two dead pups and three recipients delivered, by cesarean section, four cloned wolf pups, weighing 450, 190, 300, and 490g, respectively. The pup that weighed 190g died within 12h after birth. The six cloned wolf pups were genetically identical to the donor wolf, and their mitochondrial DNA originated from the oocyte donors. The three live wolf pups had a normal wolf karyotype (78, XY), and the amount of telomeric DNA, assessed by quantitative fluorescence in situ hybridization, was similar to, or lower than, that of the nuclear donor. In conclusion, the present study demonstrated the successful cloning of an endangered male gray wolf via interspecies transfer of somatic cells, isolated postmortem from a wolf, and transferred into enucleated dog oocytes. Therefore, somatic cell nuclear transfer has potential for preservation of canine species in extreme situations, including sudden death.

  15. Effect of TH-lines and clones on the growth and differentiation of B cell clones in microculture.

    Science.gov (United States)

    Kotloff, D B; Cebra, J J

    1988-02-01

    Antibody isotype expression by B cell clones was analyzed using in vitro microcultures containing low numbers of hapten-gelatin-enriched B cells and higher numbers of hemocyanin-specific helper T cell lines or clones. Twenty-eight to sixty-three percent of clones grown in microculture with haptenated hemocyanin and T cells from established lines expressed IgG and/or IgA isotypes in random mixtures, almost always accompanied by IgM. Helper T cells from hemocyanin-specific clones also supported the expression of non-IgM isotypes by the B cell clones, suggesting that a single specificity of T cell can provide sufficient growth and differentiation factors for the display of isotype switching. A positive correlation between the antibody output of clones and the expression of non-IgM isotypes indicated that the switching process may be associated with cell division. Although memory B cells that give clones expressing IgG and/or IgA in the absence of IgM are also enriched on haptenated gelatin, they are not stimulable under conditions of this microculture assay.

  16. T-cell clones from Th1, Th17 or Th1/17 lineages and their signature cytokines have different capacity to activate endothelial cells or synoviocytes.

    Science.gov (United States)

    Lavocat, Fabien; Maggi, Laura; Annunziato, Francesco; Miossec, Pierre

    2016-12-01

    To compare the direct effect of cytokines on synoviocytes and endothelial cells to the effects of supernatants from Th1, Th17 and Th1/17 clones and the direct cell-cell interactions with the same clones. Th17 and Th1/17 clones were obtained from the CD161+CCR6+ fraction and Th1 clones from the CD161-CCR6- fraction of human CD4+ T-cells. Endothelial cells or synoviocytes were cultured in the presence of either isolated pro-inflammatory cytokines (IL-17 and/or TNF-α) or supernatants from the T-cell clones or co-cultured with T-cell clones themselves. IL-6 and IL-8 expression and production were analyzed. IL-17 and TNF-α induced IL-6 and IL-8 expression, although IL-17 alone had a limited effect on endothelial cells compared to synoviocytes. Supernatants from activated T-helper clones also induced IL-6 and IL-8 expression but with discrepancies between endothelial cells and synoviocytes. Endothelial cells were mostly activated by Th1 clone supernatants whereas synoviocytes were activated by all T-cell subtypes. Finally, cell-cell contact experiments showed a great heterogeneity among cell clones, even from the same lineage. IL-6 expression was mostly induced by contact with Th1 clones both in endothelial and mesenchymal cells whereas IL-8 expression was induced by all T-cell clones whatever their phenotype. We showed that endothelial cells were much more sensitive to Th1 activation whereas synoviocytes were activated by all T-helper lineages. This work highlights the heterogeneity of interactions between T-cells and stromal cells through soluble factors or direct cell contact. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Isolation and expression of human cytokine synthesis inhibitory factor cDNA clones: Homology to Epstein-Barr virus open reading frame BCRFI

    Energy Technology Data Exchange (ETDEWEB)

    Vieira, P.; De Waal-Malefyt, R.; Dang, M.N.; Johnson, K.E.; Kastelein, R.; Fiorentino, D.F.; DeVries, J.E.; Roncarolo, M.G.; Mosmann, T.R.; Moore, K.W. (DNAX Research Inst. of Molecular and Cellular Biology, Palo Alto, CA (United States))

    1991-02-15

    The authors demonstrated the existence of human cytokine synthesis inhibitory factor (DSIF) (interleukin 10 (IL-10)). cDNA clones encoding human IL-10 (hIL-10) were isolated from a tetanus toxin-specific human T-cell clone. Like mouse IL-10, hIL-10 exhibits strong DNA and amino acid sequence homology to an open reading frame in the Epstein-Barr virus, BDRFL. hIL-10 and the BCRFI product inhibit cytokine synthesis by activated human peripheral blood mononuclear cells and by a mouse Th1 clone. Both hIL-10 and mouse IL-10 sustain the viability of a mouse mast cell line in culture, but BCRFI lacks comparable activity in this way, suggesting that BCRFI may have conserved only a subset of hIL-10 activities.

  18. Isolation and expression of human cytokine synthesis inhibitory factor cDNA clones: Homology to Epstein-Barr virus open reading frame BCRFI

    International Nuclear Information System (INIS)

    Vieira, P.; De Waal-Malefyt, R.; Dang, M.N.; Johnson, K.E.; Kastelein, R.; Fiorentino, D.F.; DeVries, J.E.; Roncarolo, M.G.; Mosmann, T.R.; Moore, K.W.

    1991-01-01

    The authors demonstrated the existence of human cytokine synthesis inhibitory factor (DSIF) [interleukin 10 (IL-10)]. cDNA clones encoding human IL-10 (hIL-10) were isolated from a tetanus toxin-specific human T-cell clone. Like mouse IL-10, hIL-10 exhibits strong DNA and amino acid sequence homology to an open reading frame in the Epstein-Barr virus, BDRFL. hIL-10 and the BCRFI product inhibit cytokine synthesis by activated human peripheral blood mononuclear cells and by a mouse Th1 clone. Both hIL-10 and mouse IL-10 sustain the viability of a mouse mast cell line in culture, but BCRFI lacks comparable activity in this way, suggesting that BCRFI may have conserved only a subset of hIL-10 activities

  19. Dogs cloned from adult somatic cells.

    Science.gov (United States)

    Lee, Byeong Chun; Kim, Min Kyu; Jang, Goo; Oh, Hyun Ju; Yuda, Fibrianto; Kim, Hye Jin; Hossein, M Shamim; Shamim, M Hossein; Kim, Jung Ju; Kang, Sung Keun; Schatten, Gerald; Hwang, Woo Suk

    2005-08-04

    Several mammals--including sheep, mice, cows, goats, pigs, rabbits, cats, a mule, a horse and a litter of three rats--have been cloned by transfer of a nucleus from a somatic cell into an egg cell (oocyte) that has had its nucleus removed. This technology has not so far been successful in dogs because of the difficulty of maturing canine oocytes in vitro. Here we describe the cloning of two Afghan hounds by nuclear transfer from adult skin cells into oocytes that had matured in vivo. Together with detailed sequence information generated by the canine-genome project, the ability to clone dogs by somatic-cell nuclear transfer should help to determine genetic and environmental contributions to the diverse biological and behavioural traits associated with the many different canine breeds.

  20. A novel SIV gag-specific CD4(+)T-cell clone suppresses SIVmac239 replication in CD4(+)T cells revealing the interplay between antiviral effector cells and their infected targets.

    Science.gov (United States)

    Ayala, Victor I; Trivett, Matthew T; Coren, Lori V; Jain, Sumiti; Bohn, Patrick S; Wiseman, Roger W; O'Connor, David H; Ohlen, Claes; Ott, David E

    2016-06-01

    To study CD4(+)T-cell suppression of AIDS virus replication, we isolated nine rhesus macaque SIVGag-specific CD4(+)T-cell clones. One responding clone, Gag68, produced a typical cytotoxic CD8(+)T-cell response: induction of intracellular IFN-γ, MIP-1α, MIP-1β, and CD107a degranulation. Gag68 effectively suppressed the spread of SIVmac239 in CD4(+)T cells with a corresponding reduction of infected Gag68 effector cells, suggesting that CD4(+)effectors need to suppress their own infection in addition to their targets to be effective. Gag68 TCR cloning and gene transfer into CD4(+)T cells enabled additional experiments with this unique specificity after the original clone senesced. Our data supports the idea that CD4(+)T cells can directly limit AIDS virus spread in T cells. Furthermore, Gag68 TCR transfer into CD4(+)T-cell clones with differing properties holds promise to better understand the suppressive effector mechanisms used by this important component of the antiviral response using the rhesus macaque model. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Isolation of a cDNA clone complementary to sequences for a 34-kilodalton protein which is a pp60v-src substrate.

    OpenAIRE

    Tomasiewicz, H G; Cook-Deegan, R; Chikaraishi, D M

    1984-01-01

    We have isolated a partial cDNA clone containing sequences complementary to a mRNA encoding a 34- to 36-kilodalton normal chicken cell protein which is a substrate for pp60v-src kinase activity. Using this 34-kilodalton cDNA clone as a probe, we determined that the size of the 34-kilodalton mRNA was 1,100 nucleotides and the level of the 34-kilodalton RNA was the same in various tissues of mature chickens but was significantly higher in chicken embryo fibroblast cells.

  2. Survival and mutation in clones derived from V79 Chinese hamster cells irradiated with multiple small exposures to far-UV and mid-UV

    International Nuclear Information System (INIS)

    Ikebuchi, M.; Osmak, M.; Hill, C.

    1987-01-01

    Clones were isolated from U81 and N80 cells that were established by irradiation of Chinese hamster V79-M12G cells on a once a day schedule with 81 and 80 fractions of 6 J m/sup -2/ far-UV and 150 Jm/sup -2/ mid-UV (UV-B), respectively. These clones were examined for UV sensitivity to cell lethality and induction of mutations at 6TG/sup r/ (resistance to 6-thioguanine) and Oua/sup R/ (resistance to ouabain) loci. Survival curves for these clones indicate that their UV sensitivities to lethality vary from that of M12G cells to that of U81 and N80 parental cells. Clones also show heterogeneity for mutability to mid-UV: For induction of 6TG/sup r/, for example, non-mutable (U814), hypomutable (U815) and hypermutable (U811) were isolated from U81 cells. The authors are investigating by chromosome analysis and repair experiments why resistance to far-UV and mid-UV cell killing in these cells appears to be induced but the resulting survivors have a heterogeneous response to mutation induction by further doses of UV light

  3. An alternative method for cDNA cloning from surrogate eukaryotic cells transfected with the corresponding genomic DNA.

    Science.gov (United States)

    Hu, Lin-Yong; Cui, Chen-Chen; Song, Yu-Jie; Wang, Xiang-Guo; Jin, Ya-Ping; Wang, Ai-Hua; Zhang, Yong

    2012-07-01

    cDNA is widely used in gene function elucidation and/or transgenics research but often suitable tissues or cells from which to isolate mRNA for reverse transcription are unavailable. Here, an alternative method for cDNA cloning is described and tested by cloning the cDNA of human LALBA (human alpha-lactalbumin) from genomic DNA. First, genomic DNA containing all of the coding exons was cloned from human peripheral blood and inserted into a eukaryotic expression vector. Next, by delivering the plasmids into either 293T or fibroblast cells, surrogate cells were constructed. Finally, the total RNA was extracted from the surrogate cells and cDNA was obtained by RT-PCR. The human LALBA cDNA that was obtained was compared with the corresponding mRNA published in GenBank. The comparison showed that the two sequences were identical. The novel method for cDNA cloning from surrogate eukaryotic cells described here uses well-established techniques that are feasible and simple to use. We anticipate that this alternative method will have widespread applications.

  4. Isolation and characterization of mesenchymal stem cells derived from bovine Wharton's jelly and their potential for use in cloning by nuclear transfer

    Directory of Open Access Journals (Sweden)

    Carolina Gonzales da Silva

    Full Text Available ABSTRACT: Wharton's jelly is a source of mesenchymal stem cells (MSCs that had not yet been tested for bovine embryo production by nuclear transfer (NT. Thus, the objective of this study was to isolate, characterize and test MSCs derived from Wharton's jelly for embryo and pregnancy production by NT in cattle. The umbilical cord was collected during calving and cells derived from Wharton's jelly (WJCs were isolated by explant and cultured in Dulbecco's Modified Eagle Medium. Skin Fibroblasts (FB were isolated after 6 months of life. Morphological analysis was performed by bright field and scanning electron microscopy (SEM during cell culture. Phenotypic and genotypic characterization by flow cytometry, immunocytochemistry, RT-PCR and differentiation induction in cell lineages were performed for WJC. In the NT procedure, oocytes at the arrested metaphase II stage were enucleated using micromanipulators, fused with WJCs or FB and later activated artificially. SEM micrographs revealed that WJCs have variable shape under culture. Mesenchymal markers of MSCs (CD29+, CD73+, CD90+ and CD105+ were expressed in bovine-derived WJC cultures, as evidenced by flow cytometry, immunocytochemistry and RT-PCR. When induced, these cells differentiated into osteocytes, chondrocytes and adipocytes. After classification, the WJCs were used in NT. Blastocyst formation rate by NT with WJCs at day 7 was 25.80±0.03%, similar to blatocyst rate with NT using skin fibroblasts (19.00±0.07%. Pregnancies were obtained and showed that WJCs constitute a new cell type for use in animal cloning.

  5. [Methicillin-sensitive Staphylococcus aureus isolates related to USA300 clone: Origin of community-genotype MRSA in Colombia?].

    Science.gov (United States)

    Escobar-Pérez, Javier Antonio; Castro, Betsy Esperanza; Márquez-Ortiz, Ricaurte Alejandro; Gaines, Sebastián; Chavarro, Bibiana; Moreno, Jaime; Leal, Aura Lucía; Vanegas, Natasha

    2014-04-01

    USA300 is a genetic lineage found both in methicillin-resistant (MRSA) and methicillin-sensitive Staphylococcus aureus (MSSA) isolates. In Colombia, hospital and community MRSA infections are caused by a USA300-related community genotype MRSA (CG-MRSA) clone. The genetic origin of this clone is unknown yet. To identify and characterize methicillin-resistant (MRSA) and methicillin-sensitive S. aureus (MSSA) isolates in order to improve the information about the origin of the CG-MRSA isolates in Colombia. USA300-related MSSA isolates were detected and characterized from a study of 184 S. aureus isolates (90 MRSA and 94 MSSA) recovered from infections. The genetic relatedness of the isolates was established by means of pulsed field gel electrophoresis (PFGE), multilocus sequence typing (MLST) and protein A gene typification ( spa typing). Among 184 isolates, 27 (14.7%) showed molecular characteristics and genetic relationship with the USA300 clone, of which 18 were MRSA and nine were MSSA. All USA300-related MRSA harbored Staphylococcal cassette chromosome mec (SCC mec ) IVc (3.1.2). In the MSSA isolates, SCC mec remnants or att B duplicate sites were not detected. In Colombia, the CG-MRSA isolates probably originated in the dissemination of an USA300-related MSSA clone which later acquired SCC mec IVc.

  6. College Students' Conceptions of Stem Cells, Stem Cell Research, and Cloning

    Science.gov (United States)

    Concannon, James P.; Siegel, Marcelle A.; Halverson, Kristy; Freyermuth, Sharyn

    2010-01-01

    In this study, we examined 96 undergraduate non-science majors' conceptions of stem cells, stem cell research, and cloning. This study was performed at a large, Midwest, research extensive university. Participants in the study were asked to answer 23 questions relating to stem cells, stem cell research, and cloning in an on-line assessment before…

  7. Molecular cloning and expression of Corynebacterium glutamicum genes for amino acid synthesis in Escherichia coli cells

    International Nuclear Information System (INIS)

    Beskrovnaya, O.Yu.; Fonshtein, M.Yu.; Kolibaba, L.G.; Yankovskii, N.K.; Debabov, V.G.

    1989-01-01

    Molecular cloning of Corynebacterium glutamicum genes for threonine and lysine synthesis has been done in Escherichia coli cells. The clonal library of EcoRI fragments of chromosomal DNA of C. glutamicum was constructed on the plasmid vector λpSL5. The genes for threonine and lysine synthesis were identified by complementation of E. coli mutations in thrB and lysA genes, respectively. Recombinant plasmids, isolated from independent ThrB + clone have a common 4.1-kb long EcoRI DNA fragment. Hybrid plasmids isolated from LysA + transductants of E. coli have common 2.2 and 3.3 kb long EcoRI fragments of C. glutamicum DNA. The hybrid plasmids consistently transduced the markers thrB + and lysA + . The Southern hybridization analysis showed that the cloned DNA fragments hybridized with the fragments of identical length in C. glutamicum chromosomes

  8. Effects of donor fibroblast cell type and transferred cloned embryo number on the efficiency of pig cloning.

    Science.gov (United States)

    Li, Zicong; Shi, Junsong; Liu, Dewu; Zhou, Rong; Zeng, Haiyu; Zhou, Xiu; Mai, Ranbiao; Zeng, Shaofen; Luo, Lvhua; Yu, Wanxian; Zhang, Shouquan; Wu, Zhenfang

    2013-02-01

    Currently, cloning efficiency in pigs is very low. Donor cell type and number of cloned embryos transferred to an individual surrogate are two major factors that affect the successful rate of somatic cell nuclear transfer (SCNT) in pigs. This study aimed to compare the influence of different donor fibroblast cell types and different transferred embryo numbers on recipients' pregnancy rate and delivery rate, the average number of total clones born, clones born alive and clones born healthy per litter, and the birth rate of healthy clones (=total number of healthy cloned piglets born /total number of transferred cloned embryos). Three types of donor fibroblasts were tested in large-scale production of cloned pigs, including fetal fibroblasts (FFBs) from four genetically similar Western swine breeds of Pietrain (P), Duroc (D), Landrace (L), and Yorkshire (Y), which are referred to as P,D,LY-FFBs, adult fibroblasts (AFBs) from the same four breeds, which are designated P,D,L,Y-AFBs, and AFBs from a Chinese pig breed of Laiwu (LW), which is referred to as LW-AFBs. Within each donor fibroblast cell type group, five transferred cloned embryo number groups were tested. In each embryo number group, 150-199, 200-249, 250-299, 300-349, or 350-450 cloned embryos were transferred to each individual recipient sow. For the entire experiment, 92,005 cloned embryos were generated from nearly 115,000 matured oocytes and transferred to 328 recipients; in total, 488 cloned piglets were produced. The results showed that the mean clones born healthy per litter resulted from transfer of embryos cloned from LW-AFBs (2.53 ± 0.34) was similar with that associated with P,D,L,Y-FFBs (2.72 ± 0.29), but was significantly higher than that resulted from P,D,L,Y-AFBs (1.47 ± 0.18). Use of LW-AFBs as donor cells for SCNT resulted in a significantly higher pregnancy rate (72.00% vs. 59.30% and 48.11%) and delivery rate (60.00% vs. 45.93% and 35.85%) for cloned embryo recipients, and a

  9. [Product safety analysis of somatic cell cloned bovine].

    Science.gov (United States)

    Hua, Song; Lan, Jie; Song, Yongli; Lu, Chenglong; Zhang, Yong

    2010-05-01

    Somatic cell cloning (nuclear transfer) is a technique through which the nucleus (DNA) of a somatic cell is transferred into an enucleated oocyte for the generation of a new individual, genetically identical to the somatic cell donor. It could be applied for the enhancement of reproduction rate and the improvement of food products involving quality, yield and nutrition. In recent years, the United States, Japan and Europe as well as other countries announced that meat and milk products made from cloned cattle are safe for human consumption. Yet, cloned animals are faced with a wide range of health problems, with a high death rate and a high incidence of disease. The precise causal mechanisms for the low efficiency of cloning remain unclear. Is it safe that any products from cloned animals were allowed into the food supply? This review focuses on the security of meat, milk and products from cloned cattle based on the available data.

  10. Cellular function reinstitution of offspring red blood cells cloned from the sickle cell disease patient blood post CRISPR genome editing

    Directory of Open Access Journals (Sweden)

    Jianguo Wen

    2017-06-01

    Full Text Available Abstract Background Sickle cell disease (SCD is a disorder of red blood cells (RBCs expressing abnormal hemoglobin-S (HbS due to genetic inheritance of homologous HbS gene. However, people with the sickle cell trait (SCT carry a single allele of HbS and do not usually suffer from SCD symptoms, thus providing a rationale to treat SCD. Methods To validate gene therapy potential, hematopoietic stem cells were isolated from the SCD patient blood and treated with CRISPR/Cas9 approach. To precisely dissect genome-editing effects, erythroid progenitor cells were cloned from single colonies of CRISPR-treated cells and then expanded for simultaneous gene, protein, and cellular function studies. Results Genotyping and sequencing analysis revealed that the genome-edited erythroid progenitor colonies were converted to SCT genotype from SCD genotype. HPLC protein assays confirmed reinstallation of normal hemoglobin at a similar level with HbS in the cloned genome-edited erythroid progenitor cells. For cell function evaluation, in vitro RBC differentiation of the cloned erythroid progenitor cells was induced. As expected, cell sickling assays indicated function reinstitution of the genome-edited offspring SCD RBCs, which became more resistant to sickling under hypoxia condition. Conclusions This study is an exploration of genome editing of SCD HSPCs.

  11. Isolation and characterization of a replication-competent molecular clone of an HIV-1 circulating recombinant form (CRF33_01B.

    Directory of Open Access Journals (Sweden)

    Kok Keng Tee

    Full Text Available A growing number of emerging HIV-1 recombinants classified as circulating recombinant forms (CRFs have been identified in Southeast Asia in recent years, establishing a molecular diversity of increasing complexity in the region. Here, we constructed a replication-competent HIV-1 clone for CRF33_01B (designated p05MYKL045.1, a newly identified recombinant comprised of CRF01_AE and subtype B. p05MYKL045.1 was reconstituted by cloning of the near full-length HIV-1 sequence from a newly-diagnosed individual presumably infected heterosexually in Kuala Lumpur, Malaysia. The chimeric clone, which contains the 5' LTR (long terminal repeat region of p93JP-NH1 (a previously isolated CRF01_AE infectious clone, showed robust viral replication in the human peripheral blood mononuclear cells. This clone demonstrated robust viral propagation and profound syncytium formation in CD4+, CXCR4-expressing human glioma NP-2 cells, indicating that p05MYKL045.1 is a CXCR4-using virus. Viral propagation, however, was not detected in various human T cell lines including MT-2, M8166, Sup-T1, H9, Jurkat, Molt-4 and PM1. p05MYKL045.1 appears to proliferate only in restricted host range, suggesting that unknown viral and/or cellular host factors may play a role in viral infectivity and replication in human T cell lines. Availability of a CRF33_01B molecular clone will be useful in facilitating the development of vaccine candidates that match the HIV-1 strains circulating in Southeast Asia.

  12. Isolation and characterization of two cDNA clones encoding for glutamate dehydrogenase in Nicotiana plumbaginifolia.

    Science.gov (United States)

    Ficarelli, A; Tassi, F; Restivo, F M

    1999-03-01

    We have isolated two full length cDNA clones encoding Nicotiana plumbaginifolia NADH-glutamate dehydrogenase. Both clones share amino acid boxes of homology corresponding to conserved GDH catalytic domains and putative mitochondrial targeting sequence. One clone shows a putative EF-hand loop. The level of the two transcripts is affected differently by carbon source.

  13. Transplantation and differentiation of donor cells in the cloned pigs

    International Nuclear Information System (INIS)

    Shimada, Arata; Tomii, Ryo; Kano, Koichiro; Nagashima, Hiroshi

    2006-01-01

    The application of nuclear transfer technology is an interesting approach to investigate stem and progenitor cell transplantation therapy. If stem cells are used as a nuclear donor, donor cells can engraft into cloned animals without histocompatible problems. However, it is still uncertain whether donor cells can engraft to cloned animal and differentiate in vivo. To address this problem, we transplanted donor cells to dermal tissues of cloned pigs developed by using preadipocytes as donor cells. Preadipocytes are adipocytic progenitor which can differentiate to mature adipocytes in vitro. We showed that the donor preadipocytes were successfully transplanted into the cloned pigs without immune rejection and they differentiated into mature adipocytes in vivo 3 weeks after transplantation. In contrast, allogenic control preadipocytes, which can differentiate in vitro, did not differentiate in vivo. These results indicate that donor progenitor cells can differentiate in cloned animal

  14. Dose dependency of the frequency of micronucleated binucleated clone cells and of division related median clone sizes difference. Pt. 2

    International Nuclear Information System (INIS)

    Hagemann, G,; Kreczik, A.; Treichel, M.

    1996-01-01

    Following irradiation of the progenitor cells the clone growth of CHO cells decreases as a result of cell losses. Lethally acting expressions of micronuclei are produced by heritable lethal mutations. The dependency of the frequency of micronucleated binucleated clone cells and of the median clone sizes difference on the radiation dose was measured and compared to non-irradiated controls. Using the cytokinesis-block-micronucleus-method binucleated cells with micronuclei were counted as ratio of all binucleated cells within a clone size distribution. This ratio (shortened: micronucleus yield) was determined for all clone size distributions, which had been exposed to different irradiation doses and incubation times. The micronucleus yields were compared to the corresponding median clone sizes differences. The micronucleus yield is linearly dependent on the dose and is independent of the incubation time. The same holds true for the division related median clone sizes difference, which as a result is also linearly dependent on the micronucleus yield. Due to the inevitably errors of the cell count of micronucleated binucleated cells, an automatic measurement of the median clone sizes differences is the preferred method for evaluation of cellular radiation sensitivity for heritable lethal mutations. This value should always be determined in addition, if clone survival fractions are used as predictive test because it allows for an estimation of the remission probability of surviving cells. (orig.) [de

  15. Identification of a novel clone, ST736, among Enterococcus faecium clinical isolates and its association with daptomycin nonsusceptibility.

    Science.gov (United States)

    Wang, Guiqing; Kamalakaran, Sitharthan; Dhand, Abhay; Huang, Weihua; Ojaimi, Caroline; Zhuge, Jian; Yee, Leslie Lee; Mayigowda, Pramod; Surendraiah, Pavan Kumar Makam; Dimitrova, Nevenka; Fallon, John T

    2014-08-01

    Resistance to daptomycin in enterococcal clinical isolates remains rare but is being increasingly reported in the United States and worldwide. There are limited data on the genetic relatedness and microbiological and clinical characteristics of daptomycin-nonsusceptible enterococcal clinical isolates. In this study, we assessed the population genetics of daptomycin-nonsusceptible Enterococcus faecium (DNSE) clinical isolates by multilocus sequence typing (MLST) and whole-genome sequencing analysis. Forty-two nonduplicate DNSE isolates and 43 randomly selected daptomycin-susceptible E. faecium isolates were included in the analysis. All E. faecium isolates were recovered from patients at a tertiary care medical center in suburban New York City from May 2009 through December 2013. The daptomycin MICs of the DNSE isolates ranged from 6 to >256 μg/ml. Three major clones of E. faecium (ST18, ST412, and ST736) were identified among these clinical isolates by MLST and whole-genome sequence-based analysis. A newly recognized clone, ST736, was seen in 32 of 42 (76.2%) DNSE isolates and in only 14 of 43 (32.6%) daptomycin-susceptible E. faecium isolates (P clone ST736 and daptomycin nonsusceptibility. The identification and potential spread of this novel E. faecium clone and its association with daptomycin nonsusceptibility constitute a challenge for patient management and infection control at our medical center. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  16. Recent advancements in cloning by somatic cell nuclear transfer.

    Science.gov (United States)

    Ogura, Atsuo; Inoue, Kimiko; Wakayama, Teruhiko

    2013-01-05

    Somatic cell nuclear transfer (SCNT) cloning is the sole reproductive engineering technology that endows the somatic cell genome with totipotency. Since the first report on the birth of a cloned sheep from adult somatic cells in 1997, many technical improvements in SCNT have been made by using different epigenetic approaches, including enhancement of the levels of histone acetylation in the chromatin of the reconstructed embryos. Although it will take a considerable time before we fully understand the nature of genomic programming and totipotency, we may expect that somatic cell cloning technology will soon become broadly applicable to practical purposes, including medicine, pharmaceutical manufacturing and agriculture. Here we review recent progress in somatic cell cloning, with a special emphasis on epigenetic studies using the laboratory mouse as a model.

  17. Recent advancements in cloning by somatic cell nuclear transfer

    Science.gov (United States)

    Ogura, Atsuo; Inoue, Kimiko; Wakayama, Teruhiko

    2013-01-01

    Somatic cell nuclear transfer (SCNT) cloning is the sole reproductive engineering technology that endows the somatic cell genome with totipotency. Since the first report on the birth of a cloned sheep from adult somatic cells in 1997, many technical improvements in SCNT have been made by using different epigenetic approaches, including enhancement of the levels of histone acetylation in the chromatin of the reconstructed embryos. Although it will take a considerable time before we fully understand the nature of genomic programming and totipotency, we may expect that somatic cell cloning technology will soon become broadly applicable to practical purposes, including medicine, pharmaceutical manufacturing and agriculture. Here we review recent progress in somatic cell cloning, with a special emphasis on epigenetic studies using the laboratory mouse as a model. PMID:23166393

  18. Sex-reversed somatic cell cloning in the mouse.

    Science.gov (United States)

    Inoue, Kimiko; Ogonuki, Narumi; Mekada, Kazuyuki; Yoshiki, Atsushi; Sado, Takashi; Ogura, Atsuo

    2009-10-01

    Somatic cell nuclear transfer has many potential applications in the fields of basic and applied sciences. However, it has a disadvantage that can never be overcome technically-the inflexibility of the sex of the offspring. Here, we report an accidental birth of a female mouse following nuclear transfer using an immature Sertoli cell. We produced a batch of 27 clones in a nuclear transfer experiment using Sertoli cells collected from neonatal male mice. Among them, one pup was female. This "male-derived female" clone grew into a normal adult and produced offspring by natural mating with a littermate. Chromosomal analysis revealed that the female clone had a 39,X karyotype, indicating that the Y chromosome had been deleted in the donor cell or at some early step during nuclear transfer. This finding suggests the possibility of resuming sexual reproduction after a single male is cloned, which should be especially useful for reviving extinct or endangered species.

  19. Human T-Cell Clones from Autoimmune Thyroid Glands: Specific Recognition of Autologous Thyroid Cells

    Science.gov (United States)

    Londei, Marco; Bottazzo, G. Franco; Feldmann, Marc

    1985-04-01

    The thyroid glands of patients with autoimmune diseases such as Graves' disease and certain forms of goiter contain infiltrating activated T lymphocytes and, unlike cells of normal glands, the epithelial follicular cells strongly express histocompatability antigens of the HLA-DR type. In a study of such autoimmune disorders, the infiltrating T cells from the thyroid glands of two patients with Graves' disease were cloned in mitogen-free interleukin-2 (T-cell growth factor). The clones were expanded and their specificity was tested. Three types of clones were found. One group, of T4 phenotype, specifically recognized autologous thyroid cells. Another, also of T4 phenotype, recognized autologous thyroid or blood cells and thus responded positively in the autologous mixed lymphocyte reaction. Other clones derived from cells that were activated in vivo were of no known specificity. These clones provide a model of a human autoimmune disease and their analysis should clarify mechanisms of pathogenesis and provide clues to abrogating these undesirable immune responses.

  20. Functional study and regional mapping of 44 hormono-regulated genes isolated from a porcine granulosa cell library

    Directory of Open Access Journals (Sweden)

    Hatey François

    2001-01-01

    Full Text Available Abstract cDNA clones from a pig granulosa cell cDNA library were isolated by differential hybridisation for follicle stimulating hormone (FSH regulation in granulosa cells in a previous study. The clones that did not match any known sequence were studied for their expression in granulosa cells (treated or not by FSH and in fresh isolated ovarian follicles mainly by comparative RT-PCR analysis. These results give functional data on genes that may be implicated in follicular growing. These ESTs have been localised on the porcine genome, using a somatic cell hybrid panel, providing new type I markers on the porcine map and information on the comparative map between humans and pigs.

  1. Entamoeba Clone-Recognition Experiments: Morphometrics, Aggregative Behavior, and Cell-Signaling Characterization.

    Science.gov (United States)

    Espinosa, Avelina; Paz-Y-Miño-C, Guillermo; Hackey, Meagan; Rutherford, Scott

    2016-05-01

    Studies on clone- and kin-discrimination in protists have proliferated during the past decade. We report clone-recognition experiments in seven Entamoeba lineages (E. invadens IP-1, E. invadens VK-1:NS, E. terrapinae, E. moshkovskii Laredo, E. moshkovskii Snake, E. histolytica HM-1:IMSS and E. dispar). First, we characterized morphometrically each clone (length, width, and cell-surface area) and documented how they differed statistically from one another (as per single-variable or canonical-discriminant analyses). Second, we demonstrated that amebas themselves could discriminate self (clone) from different (themselves vs. other clones). In mix-cell-line cultures between closely-related (E. invadens IP-1 vs. E. invadens VK-1:NS) or distant-phylogenetic clones (E. terrapinae vs. E. moshkovskii Laredo), amebas consistently aggregated with same-clone members. Third, we identified six putative cell-signals secreted by the amebas (RasGap/Ankyrin, coronin-WD40, actin, protein kinases, heat shock 70, and ubiquitin) and which known functions in Entamoeba spp. included: cell proliferation, cell adhesion, cell movement, and stress-induced encystation. To our knowledge, this is the first multi-clone characterization of Entamoeba spp. morphometrics, aggregative behavior, and cell-signaling secretion in the context of clone-recognition. Protists allow us to study cell-cell recognition from ecological and evolutionary perspectives. Modern protistan lineages can be central to studies about the origins and evolution of multicellularity. © 2016 The Author(s) Journal of Eukaryotic Microbiology © 2016 International Society of Protistologists.

  2. Construction and characterisation of a full-length infectious molecular clone from a fast replicating, X4-tropic HIV-1 CRF02.AG primary isolate

    International Nuclear Information System (INIS)

    Tebit, Denis M.; Zekeng, Leopold; Kaptue, Lazare; Kraeusslich, Hans-Georg; Herchenroeder, Ottmar

    2003-01-01

    Based on our previous analysis of HIV-1 isolates from Cameroon, we constructed a full-length infectious molecular clone from a primary isolate belonging to the CRF02.AG group of recombinant viruses which dominate the HIV-epidemic in West and Central Africa. The virus derived by transfection of the proviral clone pBD6-15 replicated with similar efficiency compared to its parental isolate and used CXCR4 as coreceptor as well. Furthermore, HIV-1 BD6-15 exhibited similar replication properties and virus yield as the reference B-type HIV-1 strain NL4-3. Sequence analysis revealed open reading frames for all structural and accessory genes apart from vpr. Phylogenetic and bootscanning analyses confirmed that BD6-15 clusters with CRF02.AG recombinant strains from West and Central Africa with similar cross-over points as described for the CRF02.AG prototype strain lbNG. Thus, pBD6-15 represents the first non-subtype B infectious molecular clone of a fast replicating, high producer, X4-tropic primary HIV-1 isolate, which had only been briefly passaged in primary cells

  3. Oncogenesis of melanoma B16 cell clones mutagenized by space environment

    International Nuclear Information System (INIS)

    Guo Yupeng; Yang Hongsheng; Tang Jingtian; Xu Mei; Geng Chuanying; Fang Qing; Xu Bo; Li Hongyan; Xiang Xing; Pan Lin

    2005-01-01

    Objective: To explore the oncogenesis of the melanoma B16 cell clones mutagenized by space environment, and find the B16 cell clones with remarkably mutated immunogenicity. Methods: B16 cells were carried by the Chinese 20th recoverable satellite to the outer space, and were harvested after 18 days' spaceflight and then monocloned. Four cell clones, which were randomly selected from the total 110 clones obtained , and the control clone were routinely cultured. The cultured cells were injected to 10 groups of C57BL/6J mice, 82.1 mice in each group. Five groups of mice received hypodermic injection and another 5 groups of mice received abdominal injection. The survival time was observed in abdominal injection groups. The mice in hypodermic injection groups were sacrificed after 14 days, the tumor, spleen and thymus were weighted, and the serum IL-2 concentration was determined. Moreover, the melanoma tumor tissues were examined histopathologically. Results: An experiment program suitable to screening space mutagenesis of B16 tumor cell clones in vivo and the observation indices were basically established. One clone was found out which was remarkably different from the control clone in latent period of tumor formation, tumor weight, survival time of the tumor-bearing mice and the expression of IL-2. Conclusions: Cultured melanoma B16 cells could be mutated by outer space environment. The further study will be focused on the influence of space environment on immunogenicity of mutagenized B16 cells. (authors)

  4. Construction and characterization of a full-length infectious cDNA clone of foot-and-mouth disease virus strain O/JPN/2010 isolated in Japan in 2010.

    Science.gov (United States)

    Nishi, Tatsuya; Onozato, Hiroyuki; Ohashi, Seiichi; Fukai, Katsuhiko; Yamada, Manabu; Morioka, Kazuki; Kanno, Toru

    2016-06-01

    A full-length infectious cDNA clone of the genome of a foot-and-mouth disease virus isolated from the 2010 epidemic in Japan was constructed and designated pSVL-f02. Transfection of Cos-7 or IBRS-2 cells with this clone allowed the recovery of infectious virus. The recovered virus had the same in vitro characterization as the parental virus with regard to antigenicity in neutralization and indirect immunofluorescence tests, plaque size and one-step growth. Pigs were experimentally infected with the parental virus or the recombinant virus recovered from pSVL-f02 transfected cells. There were no significant differences in clinical signs or antibody responses between the two groups, and virus isolation and viral RNA detection from clinical samples were similar. Virus recovered from transfected cells therefore retained the in vitro characteristics and the in vivo pathogenicity of their parental strain. This cDNA clone should be a valuable tool to analyze determinants of pathogenicity and mechanisms of virus replication, and to develop genetically engineered vaccines against foot-and-mouth disease virus. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Cloning of a glutathione S-transferase decreasing during differentiation of HL60 cell line

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Chul; Park, In Kyu; Lee, Kyu Bo; Sohn, Sang Kyun; Kim, Moo Kyu; Kim, Jung Chul [College of Medicine, Kyungpook National Univ., Taegu (Korea, Republic of)

    1999-06-01

    By sequencing the Expressed Sequence Tags of human dermal papilla cDNA library, we identified a clone named K872 of which the expression decreased during differentiation of HL60 cell line. K872 plasmid DNA was isolated according to QIA plasmid extraction kit (Qiagen GmbH, Germany). The nucleotide sequencing was performed by Sanger's method with K872 plasmid DNA. The most updated GenBank EMBL necleic acid banks were searched through the internet by using BLAST (Basic Local Alignment Search Tools) program. Northern bots were performed using RNA isolated from various human tissues and cancer cell lines. The gene expression of the fusion protein was achieved by His-Patch Thiofusion expression system and the protein product was identified on SDS-PAGE. K872 clone is 1006 nucleotides long, and has a coding region of 675 nucleotides and a 3' non-coding region of 280 nucleotides. The presumed open reading frame starting at the 5' terminus of K872 encodes 226 amino acids, including the initiation methionine residue. The amino acid sequence deduced from the open reading frame of K872 shares 70% identity with that of rat glutathione S-transferase kappa 1 (rGSTK1). The transcripts were expressed inh a variety of human tissues and cancer cells. The levels of transcript were relatively high in those tissues such as heart, skeletal muscle, and peripheral blood leukocyte. It is noteworthy that K872 was found to be abundantly expressed in colorectal cancer and melanoma cell lines. Homology search result suggests that K872 clone is the human homolog of the rGSTK1 which is known to be involved in the resistance of cytotoxic therapy. We propose that meticulous functional analysis should be followed to confirm that.

  6. Quantum dot-based molecular imaging of cancer cell growth using a clone formation assay.

    Science.gov (United States)

    Geng, Xia-Fei; Fang, Min; Liu, Shao-Ping; Li, Yan

    2016-10-01

    This aim of the present study was to investigate clonal growth behavior and analyze the proliferation characteristics of cancer cells. The MCF‑7 human breast cancer cell line, SW480 human colon cancer cell line and SGC7901 human gastric cancer cell line were selected to investigate the morphology of cell clones. Quantum dot‑based molecular targeted imaging techniques (which stained pan‑cytokeratin in the cytoplasm green and Ki67 in the cell nucleus yellow or red) were used to investigate the clone formation rate, cell morphology, discrete tendency, and Ki67 expression and distribution in clones. From the cell clone formation assay, the MCF‑7, SW480 and SGC7901 cells were observed to form clones on days 6, 8 and 12 of cell culture, respectively. These three types of cells had heterogeneous morphology, large nuclear:cytoplasmic ratios, and conspicuous pathological mitotic features. The cells at the clone periphery formed multiple pseudopodium. In certain clones, cancer cells at the borderline were separated from the central cell clusters or presented a discrete tendency. With quantum dot‑based molecular targeted imaging techniques, cells with strong Ki67 expression were predominantly shown to be distributed at the clone periphery, or concentrated on one side of the clones. In conclusion, cancer cell clones showed asymmetric growth behavior, and Ki67 was widely expressed in clones of these three cell lines, with strong expression around the clones, or aggregated at one side. Cell clone formation assay based on quantum dots molecular imaging offered a novel method to study the proliferative features of cancer cells, thus providing a further insight into tumor biology.

  7. Mouse cloning and somatic cell reprogramming using electrofused blastomeres.

    Science.gov (United States)

    Riaz, Amjad; Zhao, Xiaoyang; Dai, Xiangpeng; Li, Wei; Liu, Lei; Wan, Haifeng; Yu, Yang; Wang, Liu; Zhou, Qi

    2011-05-01

    Mouse cloning from fertilized eggs can assist development of approaches for the production of "genetically tailored" human embryonic stem (ES) cell lines that are not constrained by the limitations of oocyte availability. However, to date only zygotes have been successfully used as recipients of nuclei from terminally differentiated somatic cell donors leading to ES cell lines. In fertility clinics, embryos of advanced embryonic stages are usually stored for future use, but their ability to support the derivation of ES cell lines via somatic nuclear transfer has not yet been proved. Here, we report that two-cell stage electrofused mouse embryos, arrested in mitosis, can support developmental reprogramming of nuclei from donor cells ranging from blastomeres to somatic cells. Live, full-term cloned pups from embryonic donors, as well as pluripotent ES cell lines from embryonic or somatic donors, were successfully generated from these reconstructed embryos. Advanced stage pre-implantation embryos were unable to develop normally to term after electrofusion and transfer of a somatic cell nucleus, indicating that discarded pre-implantation human embryos could be an important resource for research that minimizes the ethical concerns for human therapeutic cloning. Our approach provides an attractive and practical alternative to therapeutic cloning using donated oocytes for the generation of patient-specific human ES cell lines.

  8. Cloning from stem cells: different lineages, different species, same story.

    Science.gov (United States)

    Oback, Björn

    2009-01-01

    Following nuclear transfer (NT), the most stringent measure of extensive donor cell reprogramming is development into viable offspring. This is referred to as cloning efficiency and quantified as the proportion of cloned embryos transferred into surrogate mothers that survive into adulthood. Cloning efficiency depends on the ability of the enucleated recipient cell to carry out the reprogramming reactions ('reprogramming ability') and the ability of the nuclear donor cell to be reprogrammed ('reprogrammability'). It has been postulated that reprogrammability of the somatic donor cell epigenome is inversely proportional to its differentiation status. In order to test this hypothesis, reprogrammability was compared between undifferentiated stem cells and their differentiated isogenic progeny. In the mouse, cells of divergent differentiation status from the neuronal, haematopoietic and skin epithelial lineage were tested. In cattle and deer, skeletal muscle and antler cells, respectively, were used as donors. No conclusive correlation between differentiation status and cloning efficiency was found, indicating that somatic donor cell type may not be the limiting factor for cloning success. This may reflect technical limitations of the NT-induced reprogramming assay. Alternatively, differentiation status and reprogrammability may be unrelated, making all cells equally difficult to reprogramme once they have left the ground state of pluripotency.

  9. Cloning an expressed gene shared by the human sex chromosomes

    International Nuclear Information System (INIS)

    Darling, S.M.; Banting, G.S.; Pym, B.; Wolfe, J.; Goodfellow, P.N.

    1986-01-01

    The existence of genes shared by mammalian sex chromosomes has been predicted on both evolutionary and functional grounds. However, the only experimental evidence for such genes in humans is the cell-surface antigen encoded by loci on the X and Y chromosomes (MIC2X and MIC2Y, respectively), which is recognized by the monoclonal antibody 12E7. Using the bacteriophage λgt11 expression system in Escherichia coli and immunoscreening techniques, the authors have isolated a cDNA clone whose primary product is recognized by 12E7. Southern blot analysis using somatic cell hybrids containing only the human X or Y chromosomes shows that the sequences reacting with the cDNA clone are localized to the sex chromosomes. In addition, the clone hybridizes to DNAs isolated from mouse cells that have been transfected with human DNA and selected for 12E7 expression on the fluorescence-activated cell sorter. The authors conclude that the cDNA clone encodes the 12E7 antigen, which is the primary product of the MIC2 loci. The clone was used to explore sequence homology between MIC2X and MIC2Y; these loci are closely related, if not identical

  10. Cloning human DNA repair genes

    International Nuclear Information System (INIS)

    Jeggo, P.A.; Carr, A.M.; Lehmann, A.R.

    1994-01-01

    Many human genes involved in the repair of UV damage have been cloned using different procedures and they have been of great value in assisting the understanding of the mechanism of nucleotide excision-repair. Genes involved in repair of ionizing radiation damage have proved more difficult to isolate. Positional cloning has localized the XRCC5 gene to a small region of chromosome 2q33-35, and a series of yeast artificial chromosomes covering this region have been isolated. Very recent work has shown that the XRCC5 gene encodes the 80 kDa subunit of the Ku DNA-binding protein. The Ku80 gene also maps to this region. Studies with fission yeast have shown that radiation sensitivity can result not only from defective DNA repair but also from abnormal cell cycle control following DNA damage. Several genes involved in this 'check-point' control in fission yeast have been isolated and characterized in detail. It is likely that a similar checkpoint control mechanism exists in human cells. (author)

  11. Cloning and expression of the receptor for human urokinase plasminogen activator, a central molecule in cell surface, plasmin dependent proteolysis

    DEFF Research Database (Denmark)

    Roldan, A.L.; Cubellis, M.V.; Masucci, M.T.

    1990-01-01

    , and therefore the capacity of cells to migrate and invade neighboring tissues. We have isolated a 1.4 kb cDNA clone coding for the entire human uPAR. An oligonucleotide synthesized on the basis of the N-terminal sequence of the purified protein was used to screen a cDNA library made from SV40 transformed human......, a size very close to that of the cloned cDNA. Expression of the uPAR cDNA in mouse cells confirms that the clone is complete and expresses a functional uPA binding protein, located on the cell surface and with properties similar to the human uPAR. Caseinolytic plaque assay, immunofluorescence analysis......The surface receptor for urokinase plasminogen activator (uPAR) has been recognized in recent years as a key molecule in regulating plasminogen mediated extracellular proteolysis. Surface plasminogen activation controls the connections between cells, basement membrane and extracellular matrix...

  12. The Combinational Use of CRISPR/Cas9 and Targeted Toxin Technology Enables Efficient Isolation of Bi-Allelic Knockout Non-Human Mammalian Clones

    Directory of Open Access Journals (Sweden)

    Satoshi Watanabe

    2018-04-01

    Full Text Available Recent advances in genome editing systems such as clustered regularly interspaced short palindromic repeats/CRISPR-associated protein-9 nuclease (CRISPR/Cas9 have facilitated genomic modification in mammalian cells. However, most systems employ transient treatment with selective drugs such as puromycin to obtain the desired genome-edited cells, which often allows some untransfected cells to survive and decreases the efficiency of generating genome-edited cells. Here, we developed a novel targeted toxin-based drug-free selection system for the enrichment of genome-edited cells. Cells were transfected with three expression vectors, each of which carries a guide RNA (gRNA, humanized Cas9 (hCas9 gene, or Clostridium perfringens-derived endo-β-galactosidase C (EndoGalC gene. Once EndoGalC is expressed in a cell, it digests the cell-surface α-Gal epitope, which is specifically recognized by BS-I-B4 lectin (IB4. Three days after transfection, these cells were treated with cytotoxin saporin-conjugated IB4 (IB4SAP for 30 min at 37 °C prior to cultivation in a normal medium. Untransfected cells and those weakly expressing EndoGalC will die due to the internalization of saporin. Cells transiently expressing EndoGalC strongly survive, and some of these surviving clones are expected to be genome-edited bi-allelic knockout (KO clones due to their strong co-expression of gRNA and hCas9. When porcine α-1,3-galactosyltransferase gene, which can synthesize the α-Gal epitope, was attempted to be knocked out, 16.7% and 36.7% of the surviving clones were bi-allelic and mono-allelic knockout (KO cells, respectively, which was in contrast to the isolation of clones in the absence of IB4SAP treatment. Namely, 0% and 13.3% of the resulting clones were bi-allelic and mono-allelic KO cells, respectively. A similar tendency was seen when other target genes such as DiGeorge syndrome critical region gene 2 and transforming growth factor-β receptor type 1 gene were

  13. Automated Cell-Cutting for Cell Cloning

    Science.gov (United States)

    Ichikawa, Akihiko; Tanikawa, Tamio; Matsukawa, Kazutsugu; Takahashi, Seiya; Ohba, Kohtaro

    We develop an automated cell-cutting technique for cell cloning. Animal cells softened by the cytochalasin treatment are injected into a microfluidic chip. The microfluidic chip contains two orthogonal channels: one microchannel is wide, used to transport cells, and generates the cutting flow; the other is thin and used for aspiration, fixing, and stretching of the cell. The injected cell is aspirated and stretched in the thin microchannel. Simultaneously, the volumes of the cell before and after aspiration are calculated; the volumes are used to calculate the fluid flow required to aspirate half the volume of the cell into the thin microchannel. Finally, we apply a high-speed flow in the orthogonal microchannel to bisect the cell. This paper reports the cutting process, the cutting system, and the results of the experiment.

  14. Human Cloning

    Science.gov (United States)

    2006-07-20

    Human Fertilization and Embryology Authority (HFEA). A team of scientists headed by Alison Murdoch at the University of Newcastle received permission...not yet reported success in isolating stem cells from a cloned human embryo. A research team headed by Ian Wilmut at the University of Edinburgh...research group, headed by Douglas Melton and Kevin Eggan, submitted their proposal to a Harvard committee composed of ethicists, scientists and public

  15. Six cloned calves produced from adult fibroblast cells after long-term culture

    Science.gov (United States)

    Kubota, Chikara; Yamakuchi, Hiroshi; Todoroki, Junichi; Mizoshita, Kazunori; Tabara, Norio; Barber, Michele; Yang, Xiangzhong

    2000-01-01

    Cloning whole animals with somatic cells as parents offers the possibility of targeted genetic manipulations in vitro such as “gene knock-out” by homologous recombination. However, such manipulation requires prolonged culture of nuclear donor cells. Previous successes in cloning have been limited to the use of cells collected either fresh or after short-term culture. Therefore, demonstration of genetic totipotency of cells after prolonged culture is pivotal to combining site-specific genetic manipulations and cloning. Here we report birth of six clones of an aged (17-year-old) Japanese Black Beef bull using ear skin fibroblast cells as nuclear donor cells after up to 3 months of in vitro culture (10–15 passages). We observed higher developmental rates for embryos derived from later passages (10 and 15) as compared with those embryos from an early passage (passage 5). The four surviving clones are now 10–12 months of age and appear normal, similar to their naturally reproduced peers. These data show that fibroblasts of aged animals remain competent for cloning, and prolonged culture does not affect the cloning competence of adult somatic donor cells. PMID:10655472

  16. Delayed reproductive death as a dominant phenotype in cell clones surviving X-irradiation

    International Nuclear Information System (INIS)

    Chang, W.P.; Little, J.B.

    1992-01-01

    Residual damage manifested as reduced cloning efficiency was observed in many of the cloned progeny of Chinese hamster ovary (CHO) cells and human carcinoma SQ-20B cells surviving X-irradiation. This stable phenotype, which we have termed delayed reproductive death, persisted for >50 generations of cell replication post-irradiation. Clones showing this phenotype were aneuploid, and formed colonies with a high proportion of giant cells. By somatic cell hybridization of CHO clones, the delayed reproductive death phenotype was found to be a dominant trait; the cloning efficiency of hybrid clones was persistently depressed, as compared with that of control hybrid cells. These results suggest that delayed reproductive death represents a specific cellular response that may persist in some of the progeny of mammalian cells for long periods after X-irradiation. (author)

  17. Irreversible barrier to the reprogramming of donor cells in cloning with mouse embryos and embryonic stem cells.

    Science.gov (United States)

    Ono, Yukiko; Kono, Tomohiro

    2006-08-01

    Somatic cloning does not always result in ontogeny in mammals, and development is often associated with various abnormalities and embryo loss with a high frequency. This is considered to be due to aberrant gene expression resulting from epigenetic reprogramming errors. However, a fundamental question in this context is whether the developmental abnormalities reported to date are specific to somatic cloning. The aim of this study was to determine the stage of nuclear differentiation during development that leads to developmental abnormalities associated with embryo cloning. In order to address this issue, we reconstructed cloned embryos using four- and eight-cell embryos, morula embryos, inner cell mass (ICM) cells, and embryonic stem cells as donor nuclei and determined the occurrence of abnormalities such as developmental arrest and placentomegaly, which are common characteristics of all mouse somatic cell clones. The present analysis revealed that an acute decline in the full-term developmental competence of cloned embryos occurred with the use of four- and eight-cell donor nuclei (22.7% vs. 1.8%) in cases of standard embryo cloning and with morula and ICM donor nuclei (11.4% vs. 6.6%) in serial nuclear transfer. Histological observation showed abnormal differentiation and proliferation of trophoblastic giant cells in the placentae of cloned concepti derived from four-cell to ICM cell donor nuclei. Enlargement of placenta along with excessive proliferation of the spongiotrophoblast layer and glycogen cells was observed in the clones derived from morula embryos and ICM cells. These results revealed that irreversible epigenetic events had already started to occur at the four-cell stage. In addition, the expression of genes involved in placentomegaly is regulated at the blastocyst stage by irreversible epigenetic events, and it could not be reprogrammed by the fusion of nuclei with unfertilized oocytes. Hence, developmental abnormalities such as placentomegaly as

  18. Cloning animals by somatic cell nuclear transfer – biological factors

    Science.gov (United States)

    Tian, X Cindy; Kubota, Chikara; Enright, Brian; Yang, Xiangzhong

    2003-01-01

    Cloning by nuclear transfer using mammalian somatic cells has enormous potential application. However, somatic cloning has been inefficient in all species in which live clones have been produced. High abortion and fetal mortality rates are commonly observed. These developmental defects have been attributed to incomplete reprogramming of the somatic nuclei by the cloning process. Various strategies have been used to improve the efficiency of nuclear transfer, however, significant breakthroughs are yet to happen. In this review we will discuss studies conducted, in our laboratories and those of others, to gain a better understanding of nuclear reprogramming. Because cattle are a species widely used for nuclear transfer studies, and more laboratories have succeeded in cloning cattle than any other specie, this review will be focused on somatic cell cloning of cattle. PMID:14614770

  19. Disease-causing mitochondrial heteroplasmy segregated within induced pluripotent stem cell clones derived from a patient with MELAS.

    Science.gov (United States)

    Folmes, Clifford D L; Martinez-Fernandez, Almudena; Perales-Clemente, Ester; Li, Xing; McDonald, Amber; Oglesbee, Devin; Hrstka, Sybil C; Perez-Terzic, Carmen; Terzic, Andre; Nelson, Timothy J

    2013-07-01

    Mitochondrial diseases display pathological phenotypes according to the mixture of mutant versus wild-type mitochondrial DNA (mtDNA), known as heteroplasmy. We herein examined the impact of nuclear reprogramming and clonal isolation of induced pluripotent stem cells (iPSC) on mitochondrial heteroplasmy. Patient-derived dermal fibroblasts with a prototypical mitochondrial deficiency diagnosed as mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS) demonstrated mitochondrial dysfunction with reduced oxidative reserve due to heteroplasmy at position G13513A in the ND5 subunit of complex I. Bioengineered iPSC clones acquired pluripotency with multilineage differentiation capacity and demonstrated reduction in mitochondrial density and oxygen consumption distinguishing them from the somatic source. Consistent with the cellular mosaicism of the original patient-derived fibroblasts, the MELAS-iPSC clones contained a similar range of mtDNA heteroplasmy of the disease-causing mutation with identical profiles in the remaining mtDNA. High-heteroplasmy iPSC clones were used to demonstrate that extended stem cell passaging was sufficient to purge mutant mtDNA, resulting in isogenic iPSC subclones with various degrees of disease-causing genotypes. On comparative differentiation of iPSC clones, improved cardiogenic yield was associated with iPSC clones containing lower heteroplasmy compared with isogenic clones with high heteroplasmy. Thus, mtDNA heteroplasmic segregation within patient-derived stem cell lines enables direct comparison of genotype/phenotype relationships in progenitor cells and lineage-restricted progeny, and indicates that cell fate decisions are regulated as a function of mtDNA mutation load. The novel nuclear reprogramming-based model system introduces a disease-in-a-dish tool to examine the impact of mutant genotypes for MELAS patients in bioengineered tissues and a cellular probe for molecular features of individual

  20. A two-plasmid strategy for engineering a dengue virus type 3 infectious clone from primary Brazilian isolate.

    Science.gov (United States)

    Santos, Jefferson J S; Cordeiro, Marli T; Bertani, Giovani R; Marques, Ernesto T A; Gil, Laura H V G

    2014-12-01

    Dengue infections represent one of the most prevalent arthropod-borne diseases worldwide, causing a wide spectrum of clinical outcomes. Engineered infectious clone is an important tool to study Dengue virus (DENV) biology. Functional full-length cDNA clones have been constructed for many positive-strand RNA viruses and have provided valuable tools for studying the molecular mechanisms involved in viral genome replication, virion assembly, virus pathogenesis and vaccine development. We report herein the successful development of an infectious clone from a primary Brazilian isolate of dengue virus 3 (DENV3) of the genotype III. Using a two-plasmid strategy, DENV3 genome was divided in two parts and cloned separately into a yeast-bacteria shuttle vector. All plasmids were assembled in yeast by homologous recombination technique and a full-length template for transcription was obtained by in vitro ligation of the two parts of the genome. Transcript-derived DENV3 is infectious upon transfection into BHK-21 cells and in vitro characterization confirmed its identity. Growth kinetics of transcript-derived DENV3 was indistinguishable from wild type DENV3. This system is a powerful tool that will help shed light on molecular features of DENV biology, as the relationship of specific mutations and DENV pathogenesis.

  1. Isolation of uv-sensitive variants of human FL cells by a viral suicide method

    International Nuclear Information System (INIS)

    Shiomi, T.; Sato, K.

    1979-01-01

    A new method (viral suicide method) for the isolation of uv-sensitive mutants is described. Colonies of mutagenized human FL cells were infected with uv-irradiated Herpes simplex viruses and surviving ones which seemed to be deficient in host cell reactivation (HCR) were examined for their uv sensitivity. Nineteen of 238 clones examined were sensitive to uv irradiation at the time of the isolation. After recloning, four of these clones have been studied and two (UVS-1 and UVS-2) of them are stable in their uv sensitivity for 4 months in culture. uv sensitivity of UVS-1, UVS-2, and the parental FL cells are as follows: the extrapolation numbers (n) are 2.2, 2.1, and 1.8 and mean lethal doses (DO) are 2.9, 3.7, and 7.8 J/m 2 for UVS-1, UVS-2, and the parental FL cells, respectively. They are no more sensitive than FL cells to x-irradiation. The ability of HCR in UVS-2 cells is apparently lower than that in FL cells, whereas UVS-1 cells are the same as FL cells in the ability

  2. Hybrid clone cells derived from human breast epithelial cells and human breast cancer cells exhibit properties of cancer stem/initiating cells.

    Science.gov (United States)

    Gauck, Daria; Keil, Silvia; Niggemann, Bernd; Zänker, Kurt S; Dittmar, Thomas

    2017-08-02

    The biological phenomenon of cell fusion has been associated with cancer progression since it was determined that normal cell × tumor cell fusion-derived hybrid cells could exhibit novel properties, such as enhanced metastatogenic capacity or increased drug resistance, and even as a mechanism that could give rise to cancer stem/initiating cells (CS/ICs). CS/ICs have been proposed as cancer cells that exhibit stem cell properties, including the ability to (re)initiate tumor growth. Five M13HS hybrid clone cells, which originated from spontaneous cell fusion events between M13SV1-EGFP-Neo human breast epithelial cells and HS578T-Hyg human breast cancer cells, and their parental cells were analyzed for expression of stemness and EMT-related marker proteins by Western blot analysis and confocal laser scanning microscopy. The frequency of ALDH1-positive cells was determined by flow cytometry using AldeRed fluorescent dye. Concurrently, the cells' colony forming capabilities as well as the cells' abilities to form mammospheres were investigated. The migratory activity of the cells was analyzed using a 3D collagen matrix migration assay. M13HS hybrid clone cells co-expressed SOX9, SLUG, CK8 and CK14, which were differently expressed in parental cells. A variation in the ALDH1-positive putative stem cell population was observed among the five hybrids ranging from 1.44% (M13HS-7) to 13.68% (M13HS-2). In comparison to the parental cells, all five hybrid clone cells possessed increased but also unique colony formation and mammosphere formation capabilities. M13HS-4 hybrid clone cells exhibited the highest colony formation capacity and second highest mammosphere formation capacity of all hybrids, whereby the mean diameter of the mammospheres was comparable to the parental cells. In contrast, the largest mammospheres originated from the M13HS-2 hybrid clone cells, whereas these cells' mammosphere formation capacity was comparable to the parental breast cancer cells. All M13HS

  3. TNP-specific Lyt-2+ cytolytic T cell clones preferentially respond to TNP-conjugated epidermal cells

    International Nuclear Information System (INIS)

    Shimada, S.; Katz, S.I.

    1985-01-01

    A most effective method for the induction of hapten-specific allergic contact sensitivity (CS) is via epicutaneous application of the hapten. Another effective method is by the administration of haptenated epidermal cells (EC) subcutaneously. The latter method induces more intense and longer lasting CS than does the subcutaneous administration of haptenated spleen cells (SC). Thus, there may be something unique about EC which, when haptenated, allows them to generate effector cells more effectively than do SC. The authors therefore, attempted to generate T cell clones that were both hapten- and epidermal-specific. Four days after painting mice with 7% trinitrochlorobenzene, draining lymph node cells were obtained and T cells were purified. These cells were co-cultured with trinitrophenylated (TNP) Langerhans cell-enriched EC. After 4 days, cells were harvested and rested on non-TNP-conjugated EC. The cells were restimulated and rested three times, and were then cloned by limiting dilution with added interleukin 2, which was then continually added. Proliferation of T cells was assessed by [ 3 H]-thymidine incorporation. Cytotoxicity assays utilized TNP-conjugated concanavalin A SC blasts or EC as targets. Clones A-2 and E-4 are Thy-1+, Lyt-2+, and L3T4-, and TNP-specific. In contrast to noncloned TNP-specific T cells, the clones proliferate preferentially in response to TNP-EC rather than TNP-SC. Also in contrast to noncloned T cells, the clones were preferentially cytotoxic for TNP-EC; compared to TNP-SC, there was an eight- to 32-fold increase in killing when TNP-EC were used as targets. Clones A-2 and E-4 therefore exhibit hapten and epidermal specificity

  4. Phenol emulsion-enhanced DNA-driven subtractive cDNA cloning: isolation of low-abundance monkey cortex-specific mRNAs

    International Nuclear Information System (INIS)

    Travis, G.H.; Sutcliffe, J.G.

    1988-01-01

    To isolate cDNA clones of low-abundance mRNAs expressed in monkey cerebral cortex but absent from cerebellum, the authors developed an improved subtractive cDNA cloning procedure that requires only modest quantities of mRNA. Plasmid DNA from a monkey cerebellum cDNA library was hybridized in large excess to radiolabeled monkey cortex cDNA in a phenol emulsion-enhanced reaction. The unhybridized cortex cDNA was isolated by chromatography on hydroxyapatite and used to probe colonies from a monkey cortex cDNA library. Of 60,000 colonies screened, 163 clones were isolated and confirmed by colony hybridization or RNA blotting to represent mRNAs, ranging from 0.001% to 0.1% abundance, specific to or highly enriched in cerebral cortex relative to cerebellum. Clones of one medium-abundance mRNA were recovered almost quantitatively. Two of the lower-abundance mRNAs were expressed at levels reduced by a factor of 10 in Alzheimer disease relative to normal human cortex. One of these was identified as the monkey preprosomatostatin I mRNA

  5. Donor cell differentiation, reprogramming, and cloning efficiency: elusive or illusive correlation?

    Science.gov (United States)

    Oback, B; Wells, D N

    2007-05-01

    Compared to other assisted reproductive technologies, mammalian nuclear transfer (NT) cloning is inefficient in generating viable offspring. It has been postulated that nuclear reprogramming and cloning efficiency can be increased by choosing less differentiated cell types as nuclear donors. This hypothesis is mainly supported by comparative mouse cloning experiments using early blastomeres, embryonic stem (ES) cells, and terminally differentiated somatic donor cells. We have re-evaluated these comparisons, taking into account different NT procedures, the use of donor cells from different genetic backgrounds, sex, cell cycle stages, and the lack of robust statistical significance when post-blastocyst development is compared. We argue that while the reprogrammability of early blastomeres appears to be much higher than that of somatic cells, it has so far not been conclusively determined whether differentiation status affects cloning efficiency within somatic donor cell lineages. Copyright (c) 2006 Wiley-Liss, Inc.

  6. In vitro development of cloned bovine embryos produced by handmade cloning using somatic cells from distinct levels of cell culture confluence.

    Science.gov (United States)

    Gerger, R P C; Ribeiro, E S; Forell, F; Bertolini, L R; Rodrigues, J L; Ambrósio, C E; Miglino, M A; Mezzalira, A; Bertolini, M

    2010-02-18

    The relationship between the level of cell confluence near the plateau phase of growth and blastocyst yield following somatic cell cloning is not well understood. We examined the effect of distinct cell culture confluence levels on in vitro development of cloned bovine embryos. In vitro-matured bovine oocytes were manually bisected and selected by DNA staining. One or two enucleated hemi-cytoplasts were paired and fused with an adult skin somatic cell. Cultured skin cells from an adult Nellore cow harvested at three distinct culture confluence levels (70-80, 80-90, and >95%) were used for construction of embryos and hemi-embryos. After activation, structures were cultured in vitro as one embryo (1 x 100%) or as aggregates of two hemi-embryos (2 x 50%) per microwell. Fusion, cleavage and blastocyst rates were compared using the chi(2) test. The fusion rate for hemi-embryos (51.4%) was lower than for embryos (67.6%), with no influence of degree of cell confluence. However, blastocyst rates improved linearly (7.0, 17.5, and 29.4%) with increases in cell confluence. We conclude that degree of cell culture confluence significantly influences subsequent embryo development; use of a cell population in high confluence (>90%) for nuclear transfer significantly improved blastocyst yield after cloning.

  7. Cloning Mice and Men: Prohibiting the Use of iPS Cells for Human Reproductive Cloning

    OpenAIRE

    Lo, Bernard; Parham, Lindsay; Alvarez-Buylla, Arturo; Cedars, Marcelle; Conklin, Bruce; Fisher, Susan; Gates, Elena; Giudice, Linda; Halme, Dina Gould; Hershon, William; Kriegstein, Arnold; Kwok, Pui-Yan; Wagner, Richard

    2010-01-01

    The use of iPSCs and tetraploid complementation for human reproductive cloning would raise profound ethical objections. Professional standards and laws that ban human reproductive cloning by somatic cell nuclear transfer should be revised to also forbid it by other methods, such as iPSCs via tetraploid complementation.

  8. Chromosome painting analysis of radiation-induced aberrant cell clones in the mouse

    International Nuclear Information System (INIS)

    Spruill, M.D.; Nath, J.; Tucker, J.D.

    1997-01-01

    In a study of the persistence of radiation-induced translocations over the life span of the mouse, we observed a number of clonal cells in peripheral blood lymphocytes. The presence of clones caused the mean frequency of aberrations at various time points to be elevated which interfered with biodosimetry. For this reason, we have corrected our data for the presence of clones. Mice were given an acute dose of 0, 1, 2, 3 or 4 Gy 137 Cs at 8 weeks of age. Aberrations were measured by painting chromosomes 2 and 8 and cells were examined for clones at 3 months and every 3 months thereafter until 21 months. Clones were identified by comparing the color photographic slides of all abnormal cells from each animal. Determination of clonality was made on the basis of similar breakpoint locations or the presence of other identifying characteristics such as unusual aberrations. To correct the frequency of translocations for the presence of clones, each clone, regardless of how many cells it contained, was counted only once. This reflects the original aberration frequency since each clone originated as only one cell. Among mice exposed to 4 Gy, the mean frequencies of aberrant cell clones ranged from 3-29% of the total number of metaphase cells scored with the highest frequency being 1 year post exposure. 32-70% of reciprocal and 19-92% of non-reciprocal translocations were clonal. A dose response relationship for clones was evident until 21 months when the unexposed animals exhibited a mean frequency of aberrant cell clones >10% of the total number of cells scored. Almost 75% of reciprocal and 95% of non-reciprocal translocations in these unexposed control animals were of clonal origin. Correction for clonal expansion greatly reduced the means and their standard errors at most time points where clonal expansion was prevalent. The biodosimetry was much improved suggesting that correction is beneficial in long-term studies

  9. Molecular characterization and clonal diversity of meticillin-resistant Staphylococcus aureus isolated from the community in Spain: emergence of clone sequence type 72.

    Science.gov (United States)

    Potel, C; Rey, S; Otero, S; Rubio, J; Álvarez, M

    2016-08-01

    Sequence type 72 meticillin-resistant Staphylococcus aureus (ST72 MRSA) was recently detected in our hospital. Although in Europe this clone is rarely isolated, it is the leading cause of community-associated MRSA infections in Korea, spreading also into hospitals, where it has also emerged as the main MRSA clone recovered from raw meat. We studied MRSA isolated from outpatients in Spain during a nine-year period. More than 70% of the isolates belonged to predominant clones found in hospitals. There was a significant increase in the ST72 prevalence. It appears that boundaries of dominance among MRSA clones have become blurred, demanding continuous surveillance. Copyright © 2016 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  10. Local circulating clones of Staphylococcus aureus in Ecuador.

    Science.gov (United States)

    Zurita, Jeannete; Barba, Pedro; Ortega-Paredes, David; Mora, Marcelo; Rivadeneira, Sebastián

    The spread of pandemic Staphylococcus aureus clones, mainly methicillin-resistant S. aureus (MRSA), must be kept under surveillance to assemble an accurate, local epidemiological analysis. In Ecuador, the prevalence of the USA300 Latin American variant clone (USA300-LV) is well known; however, there is little information about other circulating clones. The aim of this work was to identify the sequence types (ST) using a Multiple-Locus Variable number tandem repeat Analysis 14-locus genotyping approach. We analyzed 132 S. aureus strains that were recovered from 2005 to 2013 and isolated in several clinical settings in Quito, Ecuador. MRSA isolates composed 46.97% (62/132) of the study population. Within MRSA, 37 isolates were related to the USA300-LV clone (ST8-MRSA-IV, Panton-Valentine Leukocidin [PVL] +) and 10 were related to the Brazilian clone (ST239-MRSA-III, PVL-). Additionally, two isolates (ST5-MRSA-II, PVL-) were related to the New York/Japan clone. One isolate was related to the Pediatric clone (ST5-MRSA-IV, PVL-), one isolate (ST45-MRSA-II, PVL-) was related to the USA600 clone, and one (ST22-MRSA-IV, PVL-) was related to the epidemic UK-EMRSA-15 clone. Moreover, the most prevalent MSSA sequence types were ST8 (11 isolates), ST45 (8 isolates), ST30 (8 isolates), ST5 (7 isolates) and ST22 (6 isolates). Additionally, we found one isolate that was related to the livestock associated S. aureus clone ST398. We conclude that in addition to the high prevalence of clone LV-ST8-MRSA-IV, other epidemic clones are circulating in Quito, such as the Brazilian, Pediatric and New York/Japan clones. The USA600 and UK-EMRSA-15 clones, which were not previously described in Ecuador, were also found. Moreover, we found evidence of the presence of the livestock associated clone ST398 in a hospital environment. Copyright © 2016 Sociedade Brasileira de Infectologia. Published by Elsevier Editora Ltda. All rights reserved.

  11. DNA Methylation in Peripheral Blood Cells of Pigs Cloned by Somatic Cell Nuclear Transfer

    DEFF Research Database (Denmark)

    Gao, Fei; Li, Shengting; Lin, Lin

    2011-01-01

    To date, the genome-wide DNA methylation status of cloned pigs has not been investigated. Due to the relatively low success rate of pig cloning by somatic cell nuclear transfer, a better understanding of the epigenetic reprogramming and the global methylation patterns associated with development...... in cloned pigs is required. In this study we applied methylation-specific digital karyotyping tag sequencing by Solexa technology and investigated the genome-wide DNA methylation profiles of peripheral blood cells in cloned pigs with normal phenotypes in comparison with their naturally bred controls....... In the result, we found that globally there was no significant difference of DNA methylation patterns between the two groups. Locus-specifically, some genes involved in embryonic development presented a generally increased level of methylation. Our findings suggest that in cloned pigs with normal phenotypes...

  12. Cloning mice and men: prohibiting the use of iPS cells for human reproductive cloning.

    Science.gov (United States)

    Lo, Bernard; Parham, Lindsay; Alvarez-Buylla, Arturo; Cedars, Marcelle; Conklin, Bruce; Fisher, Susan; Gates, Elena; Giudice, Linda; Halme, Dina Gould; Hershon, William; Kriegstein, Arnold; Kwok, Pui-Yan; Wagner, Richard

    2010-01-08

    The use of iPSCs and tetraploid complementation for human reproductive cloning would raise profound ethical objections. Professional standards and laws that ban human reproductive cloning by somatic cell nuclear transfer should be revised to also forbid it by other methods, such as iPSCs via tetraploid complementation. Copyright 2010 Elsevier Inc. All rights reserved.

  13. Clonal structure of Trypanosoma cruzi Colombian strain (biodeme Type III: biological, isoenzymic and histopathological analysis of seven isolated clones

    Directory of Open Access Journals (Sweden)

    Camandaroba Edson Luiz Paes

    2001-01-01

    Full Text Available The clonal structure of the Colombian strain of Trypanosoma cruzi, biodeme Type III and zymodeme 1, was analyzed in order to characterize its populations and to establish its homogeneity or heterogeneity. Seven isolated clones presented the basic characteristics of Biodeme Type III, with the same patterns of parasitemic curves, tissue tropism to skeletal muscle and myocardium, high pathogenicity with extensive necrotic-inflammatory lesions from the 20th to 30th day of infection. The parental strain and its clones C1, C3, C4 and C6, determined the higher levels of parasitemia, 20 to 30 days of infection, with high mortality rate up to 30 days (79 to 100%; clones C2, C5 and C7 presented lower levels of parasitemia, with low mortality rates (7.6 to 23%. Isoenzymic patterns, characteristic of zymodeme 1, (Z1 were similar for the parental strain and its seven clones. Results point to a phenotypic homogeneity of the clones isolated from the Colombian strain and suggest the predominance of a principal clone, responsible for the biological behavior of the parental strain and clones.

  14. Statistical analysis of clone formation in cultures of human stem cells.

    Science.gov (United States)

    Bochkov, N P; Vinogradova, M S; Volkov, I K; Voronina, E S; Kuleshov, N P

    2011-08-01

    We performed a statistical analysis of clone formation from aneuploid cells (chromosomes 6, 8, 11, X) in cultures of bone marrow-derived human multipotent mesenchymal stromal cells by spontaneous level of aneuploidy at different terms of culturing (from 2 to 19 cell cycles). It was found that the duration of cell cycle increased from 65.6 h at passages 2-3 to 164.5 h at passage 12. The expected ratio of aneuploid cells was calculated using modeled 5, 10, 20 and 30% selective preference in reproduction. The size of samples for detecting 10, 25, and 50% increased level of aneuploidy was calculated. The presented principles for evaluation of aneuploid clone formation may be used to distinguish clones of any abnormal cells.

  15. Isolation of BAC Clones Containing Conserved Genes from Libraries of Three Distantly Related Moths: A Useful Resource for Comparative Genomics of Lepidoptera

    Directory of Open Access Journals (Sweden)

    Yuji Yasukochi

    2011-01-01

    Full Text Available Lepidoptera, butterflies and moths, is the second largest animal order and includes numerous agricultural pests. To facilitate comparative genomics in Lepidoptera, we isolated BAC clones containing conserved and putative single-copy genes from libraries of three pests, Heliothis virescens, Ostrinia nubilalis, and Plutella xylostella, harboring the haploid chromosome number, =31, which are not closely related with each other or with the silkworm, Bombyx mori, (=28, the sequenced model lepidopteran. A total of 108–184 clones representing 101–182 conserved genes were isolated for each species. For 79 genes, clones were isolated from more than two species, which will be useful as common markers for analysis using fluorescence in situ hybridization (FISH, as well as for comparison of genome sequence among multiple species. The PCR-based clone isolation method presented here is applicable to species which lack a sequenced genome but have a significant collection of cDNA or EST sequences.

  16. A Polymerase Chain Reaction-Based Method for Isolating Clones from a Complimentary DNA Library in Sheep

    Science.gov (United States)

    Friis, Thor Einar; Stephenson, Sally; Xiao, Yin; Whitehead, Jon

    2014-01-01

    The sheep (Ovis aries) is favored by many musculoskeletal tissue engineering groups as a large animal model because of its docile temperament and ease of husbandry. The size and weight of sheep are comparable to humans, which allows for the use of implants and fixation devices used in human clinical practice. The construction of a complimentary DNA (cDNA) library can capture the expression of genes in both a tissue- and time-specific manner. cDNA libraries have been a consistent source of gene discovery ever since the technology became commonplace more than three decades ago. Here, we describe the construction of a cDNA library using cells derived from sheep bones based on the pBluescript cDNA kit. Thirty clones were picked at random and sequenced. This led to the identification of a novel gene, C12orf29, which our initial experiments indicate is involved in skeletal biology. We also describe a polymerase chain reaction-based cDNA clone isolation method that allows the isolation of genes of interest from a cDNA library pool. The techniques outlined here can be applied in-house by smaller tissue engineering groups to generate tools for biomolecular research for large preclinical animal studies and highlights the power of standard cDNA library protocols to uncover novel genes. PMID:24447069

  17. Comparative Genome Analyses of Streptococcus suis Isolates from Endocarditis Demonstrate Persistence of Dual Phenotypic Clones.

    Science.gov (United States)

    Tohya, Mari; Watanabe, Takayasu; Maruyama, Fumito; Arai, Sakura; Ota, Atsushi; Athey, Taryn B T; Fittipaldi, Nahuel; Nakagawa, Ichiro; Sekizaki, Tsutomu

    2016-01-01

    Many bacterial species coexist in the same niche as heterogeneous clones with different phenotypes; however, understanding of infectious diseases by polyphenotypic bacteria is still limited. In the present study, encapsulation in isolates of the porcine pathogen Streptococcus suis from persistent endocarditis lesions was examined. Coexistence of both encapsulated and unencapsulated S. suis isolates was found in 26 out of 59 endocarditis samples. The isolates were serotype 2, and belonged to two different sequence types (STs), ST1 and ST28. The genomes of each of the 26 pairs of encapsulated and unencapsulated isolates from the 26 samples were sequenced. The data showed that each pair of isolates had one or more unique nonsynonymous mutations in the cps gene, and the encapsulated and unencapsulated isolates from the same samples were closest to each other. Pairwise comparisons of the sequences of cps genes in 7 pairs of encapsulated and unencapsulated isolates identified insertion/deletions (indels) ranging from one to 104 bp in different cps genes of unencapsulated isolates. Capsule expression was restored in a subset of unencapsulated isolates by complementation in trans with cps expression vectors. Examination of gene content common to isolates indicated that mutation frequency was higher in ST28 pairs than in ST1 pairs. Genes within mobile genetic elements were mutation hot spots among ST28 isolates. Taken all together, our results demonstrate the coexistence of dual phenotype (encapsulated and unencapsulated) bacterial clones and suggest that the dual phenotypes arose independently in each farm by means of spontaneous mutations in cps genes.

  18. Comparative Genome Analyses of Streptococcus suis Isolates from Endocarditis Demonstrate Persistence of Dual Phenotypic Clones.

    Directory of Open Access Journals (Sweden)

    Mari Tohya

    Full Text Available Many bacterial species coexist in the same niche as heterogeneous clones with different phenotypes; however, understanding of infectious diseases by polyphenotypic bacteria is still limited. In the present study, encapsulation in isolates of the porcine pathogen Streptococcus suis from persistent endocarditis lesions was examined. Coexistence of both encapsulated and unencapsulated S. suis isolates was found in 26 out of 59 endocarditis samples. The isolates were serotype 2, and belonged to two different sequence types (STs, ST1 and ST28. The genomes of each of the 26 pairs of encapsulated and unencapsulated isolates from the 26 samples were sequenced. The data showed that each pair of isolates had one or more unique nonsynonymous mutations in the cps gene, and the encapsulated and unencapsulated isolates from the same samples were closest to each other. Pairwise comparisons of the sequences of cps genes in 7 pairs of encapsulated and unencapsulated isolates identified insertion/deletions (indels ranging from one to 104 bp in different cps genes of unencapsulated isolates. Capsule expression was restored in a subset of unencapsulated isolates by complementation in trans with cps expression vectors. Examination of gene content common to isolates indicated that mutation frequency was higher in ST28 pairs than in ST1 pairs. Genes within mobile genetic elements were mutation hot spots among ST28 isolates. Taken all together, our results demonstrate the coexistence of dual phenotype (encapsulated and unencapsulated bacterial clones and suggest that the dual phenotypes arose independently in each farm by means of spontaneous mutations in cps genes.

  19. Comparative Genome Analyses of Streptococcus suis Isolates from Endocarditis Demonstrate Persistence of Dual Phenotypic Clones

    Science.gov (United States)

    Tohya, Mari; Watanabe, Takayasu; Maruyama, Fumito; Arai, Sakura; Ota, Atsushi; Athey, Taryn B. T.; Fittipaldi, Nahuel; Nakagawa, Ichiro; Sekizaki, Tsutomu

    2016-01-01

    Many bacterial species coexist in the same niche as heterogeneous clones with different phenotypes; however, understanding of infectious diseases by polyphenotypic bacteria is still limited. In the present study, encapsulation in isolates of the porcine pathogen Streptococcus suis from persistent endocarditis lesions was examined. Coexistence of both encapsulated and unencapsulated S. suis isolates was found in 26 out of 59 endocarditis samples. The isolates were serotype 2, and belonged to two different sequence types (STs), ST1 and ST28. The genomes of each of the 26 pairs of encapsulated and unencapsulated isolates from the 26 samples were sequenced. The data showed that each pair of isolates had one or more unique nonsynonymous mutations in the cps gene, and the encapsulated and unencapsulated isolates from the same samples were closest to each other. Pairwise comparisons of the sequences of cps genes in 7 pairs of encapsulated and unencapsulated isolates identified insertion/deletions (indels) ranging from one to 104 bp in different cps genes of unencapsulated isolates. Capsule expression was restored in a subset of unencapsulated isolates by complementation in trans with cps expression vectors. Examination of gene content common to isolates indicated that mutation frequency was higher in ST28 pairs than in ST1 pairs. Genes within mobile genetic elements were mutation hot spots among ST28 isolates. Taken all together, our results demonstrate the coexistence of dual phenotype (encapsulated and unencapsulated) bacterial clones and suggest that the dual phenotypes arose independently in each farm by means of spontaneous mutations in cps genes. PMID:27433935

  20. Cloning and expression of pab gene of M. tuberculosis isolated from pulmonary TB patient in E.coli DH5α

    Directory of Open Access Journals (Sweden)

    Tri Y. M. Raras

    2011-11-01

    Full Text Available Background: Mycobacterium tuberculosis antigen38 is a potent serodiagnostic agent containing two M. tuberculosisspecific B-cell epitopes. The high price of imported diagnostic agents hinders realization of fast clinical TB diagnosis in developing countries. Therefore, we produced recombinant antigen38 (recAg38M from M. tuberculosis local strain, which might be used to produce economical tuberculosis serodiagnostic kit.Methods: Pab gene that was isolated from pulmonary TB patient in Malang was cloned into a plasmid vector (pGEMTeasy to construct pMB38. The E.coli DH5α clone carrying pMb38 was selected on X-gal medium. The expression of pab was mediated using pPRoExHTc under the control of Trc promoter and E.coli DH5α as host.Results: Alignment of the pab sequence from the white E.coli DH5α clones with that of M. tuberculosis H37Rv showed 98% homology. The recombinant protein in which the signal peptide has been deleted to prevent the protein being secreted into medium was found in the cytoplasm.Conclusion: pab gene of M. tuberculosis isolated from a TB patient could be expressed in heterologous system in E.coliDH5α. (Med J Indones 2011; 20:247-54Keywords: Mycobacterium tuberculosis, Pab gene expression, recombinant antigen38

  1. Numbers and dispersion of repopulating hematopoietic cell clones in radiation chimeras as functions of injected cell dose

    International Nuclear Information System (INIS)

    Micklem, H.S.; Lennon, J.E.; Ansell, J.D.; Gray, R.A.

    1987-01-01

    Lethally irradiated mice were repopulated with low (10(5)), medium (10(6)) or high (10(7)) doses of congenic bone marrow cells. Marrow donors were heterozygous for the X-chromosome-encoded allozyme marker phosphoglycerate kinase (PGK-1). A second allozyme marker, phosphoglucose isomerase (GPI-1), distinguished between donor and radioresistant host cells. Use of these markers allowed the numbers and dispersion of repopulating hematopoietic clones to be estimated by binomial statistics. The number of major repopulating clones was related to the injected cell dose in a linear fashion, the inferred frequency of clonogenic cells in donor bone marrow being about 1:40,000. In high-dose recipients, the clones grew locally, with little or no dispersion between bones. Low-dose recipients, in contrast, carried widely dispersed clones; these tended to become reduced in number with increasing time after repopulation. Most of the (few) bone marrow clones present in low-dose recipients were also present in the thymus. In contrast, only about 10% of bone marrow clones in high-dose recipients were substantially represented in the thymus at any one time--about 16 clones in each lobe

  2. Coding sequence of human rho cDNAs clone 6 and clone 9

    Energy Technology Data Exchange (ETDEWEB)

    Chardin, P; Madaule, P; Tavitian, A

    1988-03-25

    The authors have isolated human cDNAs including the complete coding sequence for two rho proteins corresponding to the incomplete isolates previously described as clone 6 and clone 9. The deduced a.a. sequences, when compared to the a.a. sequence deduced from clone 12 cDNA, show that there are in human at least three highly homologous rho genes. They suggest that clone 12 be named rhoA, clone 6 : rhoB and clone 9 : rhoC. RhoA, B and C proteins display approx. 30% a.a. identity with ras proteins,. mainly clustered in four highly homologous internal regions corresponding to the GTP binding site; however at least one significant difference is found; the 3 rho proteins have an Alanine in position corresponding to ras Glycine 13, suggesting that rho and ras proteins might have slightly different biochemical properties.

  3. Lysis of cells infected with typhus group rickettsiae by a human cytotoxic T cell clone

    International Nuclear Information System (INIS)

    Carl, M.; Robbins, F.; Hartzman, R.J.; Dasch, G.A.

    1987-01-01

    Cytolytic human T cells clones generated in response to the intracellular bacterium Rickettsia typhi were characterized. Growing clones were tested for their ability to proliferate specifically in response to antigens derived from typhus group rickettsiae or to lyse targets infected with R. typhi or Rickettsia prowazekii, as measured by 51 Cr-release from target cells. Two clones were able to lyse targets infected with typhus group rickettsiae. One of these clones was more fully characterized because of its rapid growth characteristics. This cytolytic clone was capable of lysing an autologous infected target as well as a target matched for class I and II histocompatibility leukocyte antigens (HLA). It was not capable, however, of lysing either a target mismatched for both class I and II HLA or a target partially matched for class I HLA. In addition, the clone exhibited specificity in that it was able to lyse an autologous target infected with typhus group rickettsiae, but did not lyse an autologous target infected with an antigenically distinct rickettsial species, Rickettsia tsutsugamushi. These results demonstrate, for the first time, that cells infected with intracellular bacteria can be lysed by human cytotoxic T lymphocytes

  4. In situ detection, isolation, and physiological properties of a thin filamentous microorganism abundant in methanogenic granular sludges: a novel isolate affiliated with a clone cluster, the green non-sulfur bacteria, subdivision I.

    Science.gov (United States)

    Sekiguchi, Y; Takahashi, H; Kamagata, Y; Ohashi, A; Harada, H

    2001-12-01

    We previously showed that very thin filamentous bacteria affiliated with the division green non-sulfur bacteria were abundant in the outermost layer of thermophilic methanogenic sludge granules fed with sucrose and several low-molecular-weight fatty acids (Y. Sekiguchi, Y. Kamagata, K. Nakamura, A. Ohashi, H. Harada, Appl. Environ. Microbiol. 65:1280-1288, 1999). Further 16S ribosomal DNA (rDNA) cloning-based analysis revealed that the microbes were classified within a unique clade, green non-sulfur bacteria (GNSB) subdivision I, which contains a number of 16S rDNA clone sequences from various environmental samples but no cultured representatives. To investigate their function in the community and physiological traits, we attempted to isolate the yet-to-be-cultured microbes from the original granular sludge. The first attempt at isolation from the granules was, however, not successful. In the other thermophilic reactor that had been treating fried soybean curd-manufacturing wastewater, we found filamentous microorganisms to outgrow, resulting in the formation of projection-like structures on the surface of granules, making the granules look like sea urchins. 16S rDNA-cloning analysis combined with fluorescent in situ hybridization revealed that the projections were comprised of the uncultured filamentous cells affiliated with the GNSB subdivision I and Methanothermobacter-like cells and the very ends of the projections were comprised solely of the filamentous cells. By using the tip of the projection as the inoculum for primary enrichment, a thermophilic, strictly anaerobic, filamentous bacterium, designated strain UNI-1, was successfully isolated with a medium supplemented with sucrose and yeast extract. The strain was a very slow growing bacterium which is capable of utilizing only a limited range of carbohydrates in the presence of yeast extract and produced hydrogen from these substrates. The growth was found to be significantly stimulated when the strain was

  5. Human cloning, stem cell research. An Islamic perspective.

    Science.gov (United States)

    Al-Aqeel, Aida I

    2009-12-01

    The rapidly changing technologies that involve human subjects raise complex ethical, legal, social, and religious issues. Recent advances in the field of cloning and stem cell research have introduced new hopes for the treatment of serious diseases. But this promise has raised many complex questions. This field causes debate and challenge, not only among scientists but also among ethicists, religious scholars, governments, and politicians. There is no consensus on the morality of human cloning, even within specific religious traditions. In countries in which religion has a strong influence on political decision making, the moral status of the human embryo is at the center of the debate. Because of the inevitable consequences of reproductive cloning, it is prohibited in Islam. However, stem cell research for therapeutic purposes is permissible with full consideration, and all possible precautions in the pre-ensoulment stages of early fetus development, if the source is legitimate.

  6. Cloning of the cDNA for human 12-lipoxygenase

    International Nuclear Information System (INIS)

    Izumi, T.; Hoshiko, S.; Radmark, O.; Samuelsson, B.

    1990-01-01

    A full-length cDNA clone encoding 12-lipoxygenase was isolated from a human platelet cDNA library by using a cDNA for human reticulocyte 15-lipoxygenase as probe for the initial screening. The cDNA had an open reading frame encoding 662 amino acid residues with a calculated molecular weight of 75,590. Three independent clones revealed minor heterogeneities in their DNA sequences. Thus, in three positions of the deduced amino acid sequence, there is a choice between two different amino acids. The deduced sequence from the clone plT3 showed 65% identity with human reticulocyte 15-lipoxygenase and 42% identity with human leukocyte 5-lipoxygenase. The 12-lipoxygenase cDNA recognized a 3.0-kilobase mRNA species in platelets and human erythroleukemia cells (HEL cells). Phorbol 12-tetradecanoyl 13-acetate induced megakaryocytic differentiation of HEL cells and 12-lipoxygenase activity and increased mRNA for 12-lipoxygenase. The identity of the cloned 12-lipoxygenase was assured by expression in a mammalian cell line (COS cells). Human platelet 12-lipoxygenase has been difficult to purify to homogeneity. The cloning of this cDNA will increase the possibilities to elucidate the structure and function of this enzyme

  7. Isolation and structure of a cDNA encoding the B1 (CD20) cell-surface antigen of human B lymphocytes

    International Nuclear Information System (INIS)

    Tender, T.F.; Streuli, M.; Schlossman, S.F.; Saito, H.

    1988-01-01

    The B1 (CD20) molecule is a M/sub r/ 33,000 phosphoprotein on the surface of human B lymphocytes that may serve a central role in the homoral immune response by regulating B-cell proliferation and differentiation. In this report, a cDNA clone that encodes the B1 molecule was isolated and the amino acid sequence of B1 was determined. B-cell-specific cDNA clones were selected from a human tonsillar cDNA library by differential hybridization with labeled cDNA derived from either size-fractionated B-cell mRNA or size-fractionated T-cell mRNA. Of the 261 cDNA clones isolated, 3 cross-hybridizing cDNA clones were chosen as potential candidates for encoding B1 based on their selective hybridization to RNA from B1-positive cell lines. The longest clone, pB1-21, contained a 2.8-kilobase insert with an 891-base-pair open reading frame that encodes a protein of 33 kDa. mRNA synthesized from the pB1-21 cDNA clone in vitro was translated into a protein of the same apparent molecular weight as B1. Limited proteinase digestion of the pB1-21 translation product and B1 generated peptides of the same sizes, indicating that the pB1-21 cDNA encodes the B1 molecule. Gel blot analysis indicated that pB1-21 hybridized with two mRNA species of 2.8 and 3.4 kilobases only in B1-positive cell lines. The amino acid sequence deduced from the pB1-21 nucleotide sequence apparently lacks a signal sequence and contains three extensive hydrophobic regions. The deduced B1 amino acid sequence shows no significant homology with other known patients

  8. Individual clones of hemopoietic cells in murine long-term bone marrow culture

    International Nuclear Information System (INIS)

    Chertkov, J.L.; Deryugina, E.I.; Drize, N.J.; Udalov, G.A.

    1987-01-01

    Forty-seven individual hemopoietic cell clones bearing unique radiation markers were studied in long-term bone marrow cultures. Throughout cultivation clones appeared at different times, from 1 to 12 weeks after explantation, survived during 1-10 more weeks, and were characterized by marked variability in size. Usually, the number of metaphases peculiar to an individual clone rapidly increased, achieved maximum, and then underwent a decline. Cells of reliably disappearing clones were never seen again. The experimental results provide further evidence for the model of hemopoiesis by clonal succession

  9. Cloning of ES cells and mice by nuclear transfer.

    Science.gov (United States)

    Wakayama, Sayaka; Kishigami, Satoshi; Wakayama, Teruhiko

    2009-01-01

    We have been able to develop a stable nuclear transfer (NT) method in the mouse, in which donor nuclei are directly injected into the oocyte using a piezo-actuated micromanipulator. Although the piezo unit is a complex tool, once mastered it is of great help not only in NT experiments, but also in almost all other forms of micromanipulation. Using this technique, embryonic stem (ntES) cell lines established from somatic cell nuclei can be generated relatively easily from a variety of mouse genotypes and cell types. Such ntES cells can be used not only for experimental models of human therapeutic cloning but also as a means of preserving mouse genomes instead of preserving germ cells. Here, we describe our most recent protocols for mouse cloning.

  10. Construction of Infectious cDNA Clone of a Chrysanthemum stunt viroid Korean Isolate

    Directory of Open Access Journals (Sweden)

    Ju-Yeon Yoon

    2014-03-01

    Full Text Available Chrysanthemum stunt viroid (CSVd, a noncoding infectious RNA molecule, causes seriously economic losses of chrysanthemum for 3 or 4 years after its first infection. Monomeric cDNA clones of CSVd isolate SK1 (CSVd-SK1 were constructed in the plasmids pGEM-T easy vector and pUC19 vector. Linear positive-sense transcripts synthesized in vitro from the full-length monomeric cDNA clones of CSVd-SK1 could infect systemically tomato seedlings and chrysanthemum plants, suggesting that the linear CSVd RNA transcribed from the cDNA clones could be replicated as efficiently as circular CSVd in host species. However, direct inoculation of plasmid cDNA clones containing full-length monomeric cDNA of CSVd-SK1 failed to infect tomato and chrysanthemum and linear negative-sense transcripts from the plasmid DNAs were not infectious in the two plant species. The cDNA sequences of progeny viroid in systemically infected tomato and chrysanthemum showed a few substitutions at a specific nucleotide position, but there were no deletions and insertions in the sequences of the CSVd progeny from tomato and chrysanthemum plants.

  11. Cloning analysis of HBV-specific CD8 T cell receptor gene in patients with acute hepatitis B

    Directory of Open Access Journals (Sweden)

    Ning DING

    2011-05-01

    Full Text Available Objective To investigate the molecular mechanism of T cell receptor(TCR in CD8 T cell-mediated immune response to HBV in patients with acute hepatitis B(AHB.Methods Peripheral blood mononuclear cells(PBMCs were collected from HLA-A2-positive AHB patients.To determine HBsAg183-191 and HBsAg335-343-specific CD8 T cell frequencies,the PBMCs were stained by fluorescence-labeled anti-CD3,anti-CD8 and pentamers,and analyzed by flow cytometry.PBMCs from 6 patients were stimulated with epitopic peptide HBsAg335-343 in vitro for 3 to 4 weeks.HBV-specific CD8 T cells were isolated by magnetic activated cell sorting followed by flow florescence activated cell sorting.The mRNA of sorted cells was extracted after expanding by IL-2,anti-CD3 and anti-CD8.The full-length gene fragments of variable region of TCR α and β chains were gained by 5’-RACE,and then cloned and sequenced(≥50 clones for single chain of each sample.The gene families of TCR α and β chains were identified and the sequence characters of CDR3 were compared.Results Analysis of more than 600 cloned gene sequences of TCR α and β chains showed that the proliferated HBV-specific CD8 T cells from 6 AHB patients presented a predominant expression in TCR α and chains,with 2-4 α chain families and 1-4 chain families in each case.The α2,α14,α15,β3,β13 and 23 families were detected in more than one case.The chain genes were all 13 for all tested clones in one case.For the same α chain or-chain family,CDR3 sequences tended to be identical in one case but different among cases.Conclusions HBV-specific CD8 T cells with antigenic peptide-induced proliferation present predominance in the usage of TCR α and β chains.This property might be one of the important molecular factors influencing anti-HBV immunity.

  12. Cloning

    Science.gov (United States)

    Cloning describes the processes used to create an exact genetic replica of another cell, tissue or organism. ... named Dolly. There are three different types of cloning: Gene cloning, which creates copies of genes or ...

  13. Interclonal variations in the molecular karyotype of Trypanosoma cruzi: chromosome rearrangements in a single cell-derived clone of the G strain.

    Science.gov (United States)

    Lima, Fabio Mitsuo; Souza, Renata Torres; Santori, Fábio Rinaldo; Santos, Michele Fernandes; Cortez, Danielle Rodrigues; Barros, Roberto Moraes; Cano, Maria Isabel; Valadares, Helder Magno Silva; Macedo, Andréa Mara; Mortara, Renato Arruda; da Silveira, José Franco

    2013-01-01

    Trypanosoma cruzi comprises a pool of populations which are genetically diverse in terms of DNA content, growth and infectivity. Inter- and intra-strain karyotype heterogeneities have been reported, suggesting that chromosomal rearrangements occurred during the evolution of this parasite. Clone D11 is a single-cell-derived clone of the T. cruzi G strain selected by the minimal dilution method and by infecting Vero cells with metacyclic trypomastigotes. Here we report that the karyotype of clone D11 differs from that of the G strain in both number and size of chromosomal bands. Large chromosomal rearrangement was observed in the chromosomes carrying the tubulin loci. However, most of the chromosome length polymorphisms were of small amplitude, and the absence of one band in clone D11 in relation to its reference position in the G strain could be correlated to the presence of a novel band migrating above or below this position. Despite the presence of chromosomal polymorphism, large syntenic groups were conserved between the isolates. The appearance of new chromosomal bands in clone D11 could be explained by chromosome fusion followed by a chromosome break or interchromosomal exchange of large DNA segments. Our results also suggest that telomeric regions are involved in this process. The variant represented by clone D11 could have been induced by the stress of the cloning procedure or could, as has been suggested for Leishmania infantum, have emerged from a multiclonal, mosaic parasite population submitted to frequent DNA amplification/deletion events, leading to a 'mosaic' structure with different individuals having differently sized versions of the same chromosomes. If this is the case, the variant represented by clone D11 would be better adapted to survive the stress induced by cloning, which includes intracellular development in the mammalian cell. Karyotype polymorphism could be part of the T. cruzi arsenal for responding to environmental pressure.

  14. Somatic cell nuclear transfer cloning: practical applications and current legislation.

    Science.gov (United States)

    Niemann, H; Lucas-Hahn, A

    2012-08-01

    Somatic cloning is emerging as a new biotechnology by which the opportunities arising from the advances in molecular genetics and genome analysis can be implemented in animal breeding. Significant improvements have been made in SCNT protocols in the past years which now allow to embarking on practical applications. The main areas of application of SCNT are: Reproductive cloning, therapeutic cloning and basic research. A great application potential of SCNT based cloning is the production of genetically modified (transgenic) animals. Somatic cell nuclear transfer based transgenic animal production has significant advances over the previously employed microinjection of foreign DNA into pronuclei of zygotes. This cell based transgenesis is compatible with gene targeting and allows both, the addition of a specific gene and the deletion of an endogenous gene. Efficient transgenic animal production provides numerous opportunities for agriculture and biomedicine. Regulatory agencies around the world have agreed that food derived from cloned animals and their offspring is safe and there is no scientific basis for questioning this. Commercial application of somatic cloning within the EU is via the Novel Food regulation EC No. 258/97. Somatic cloning raises novel questions regarding the ethical and moral status of animals and their welfare which has prompted a controversial discussion in Europe which has not yet been resolved. © 2012 Blackwell Verlag GmbH.

  15. Recombinant human albumin supports single cell cloning of CHO cells in chemically defined media.

    Science.gov (United States)

    Zhu, Jiang; Wooh, Jong Wei; Hou, Jeff Jia Cheng; Hughes, Benjamin S; Gray, Peter P; Munro, Trent P

    2012-01-01

    Biologic drugs, such as monoclonal antibodies, are commonly made using mammalian cells in culture. The cell lines used for manufacturing should ideally be clonal, meaning derived from a single cell, which represents a technically challenging process. Fetal bovine serum is often used to support low cell density cultures, however, from a regulatory perspective, it is preferable to avoid animal-derived components to increase process consistency and reduce the risk of contamination from adventitious agents. Chinese hamster ovary (CHO) cells are the most widely used cell line in industry and a large number of serum-free, protein-free, and fully chemically defined growth media are commercially available, although these media alone do not readily support efficient single cell cloning. In this work, we have developed a simple, fully defined, single-cell cloning media, specifically for CHO cells, using commercially available reagents. Our results show that a 1:1 mixture of CD-CHO™ and DMEM/F12 supplemented with 1.5 g/L of recombinant albumin (Albucult®) supports single cell cloning. This formulation can support recovery of single cells in 43% of cultures compared to 62% in the presence of serum. Copyright © 2012 American Institute of Chemical Engineers (AIChE).

  16. Isolation and characterization of portal branch ligation-stimulated Hmga2-positive bipotent hepatic progenitor cells

    International Nuclear Information System (INIS)

    Sakai, Hiroshi; Tagawa, Yoh-ichi; Tamai, Miho; Motoyama, Hiroaki; Ogawa, Shinichiro; Soeda, Junpei; Nakata, Takenari; Miyagawa, Shinichi

    2010-01-01

    Research highlights: → Hepatic progenitor cells were isolated from the portal branch-ligated liver of mice. → Portal branch ligation-stimulated hepatic progenitor cells (PBLHCs) express Hmga2. → PBLHCs have bidirectional differentiation capability in vitro. -- Abstract: Hepatic stem/progenitor cells are one of several cell sources that show promise for restoration of liver mass and function. Although hepatic progenitor cells (HPCs), including oval cells, are induced by administration of certain hepatotoxins in experimental animals, such a strategy would be inappropriate in a clinical setting. Here, we investigated the possibility of isolating HPCs in a portal branch-ligated liver model without administration of any chemical agents. A non-parenchymal cell fraction was prepared from the portal branch-ligated or non-ligated lobe, and seeded onto plates coated with laminin. Most of the cells died, but a small number were able to proliferate. These proliferating cells were cloned as portal branch ligation-stimulated hepatic cells (PBLHCs) by the limiting dilution method. The PBLHCs expressed cytokeratin19, albumin, and Hmga2. The PBLHCs exhibited metabolic functions such as detoxification of ammonium ions and synthesis of urea on Matrigel-coated plates in the presence of oncostatin M. In Matrigel mixed with type I collagen, the PBLHCs became rearranged into cystic and tubular structures. Immunohistochemical staining demonstrated the presence of Hmga2-positive cells around the interlobular bile ducts in the portal branch-ligated liver lobes. In conclusion, successful isolation of bipotent hepatic progenitor cell clones, PBLHCs, from the portal branch-ligated liver lobes of mice provides the possibility of future clinical application of portal vein ligation to induce hepatic progenitor cells.

  17. [Distribution of abnormal cell clone with deletion of chromosome 20q in marrow cell lineages and apoptosis cells in myelodysplastic syndrome].

    Science.gov (United States)

    Qin, Ling; Wang, Chun; Qin, You-Wen; Xie, Kuang-Cheng; Yan, Shi-Ke; Gao, Yan-Rong; Wang, Xiao-Rui; Zhao, Chu-Xian

    2008-06-01

    This study was aimed to investigate the distribution of abnormal clone in marrow cell lineages and apoptosis cells in myelodysplastic syndrome (MDS) with deletion of chromosome 20q. Monoclonal antibodies recognizing myeloid precursors (CD15), erythroid precursors (GPA), T cells (CD3(+)CD56(-)CD16(-)), B cells (CD19), NK cells (CD3(-)CD56(+)CD16(+)) were used to sort bone marrow cells in a MDS patient with del (20q) by fluorescence activated cell sorting (FACS). Annexin V-FITC and PI were used to sort bone marrow Annexin V(+)PI(-) and Annexin V(-)PI(-) cells by FACS. The sorted positive cells were detected by interphase dual-color fluorescence in situ hybridization (D-FISH) using a LSI D20S108 probe (Spectrum Orange) and a Telvysion TM 20p probe (Spectrum Green). FACS and FISH analysis were also performed on the samples from 4 cases with normal karyotype. The results showed that the proportions of MDS clone in the myeloid and erythroid precursors were 70.50% and 93.33% respectively, in the RAEB-1 patient with del (20q) and were obviously higher than that in control group (5.39% and 6.17%). The proportions of abnormal clone in T, B and NK cells were 3.23%, 4.32% and 5.77% respectively and were less than that in control group (5.76%, 4.85%, 6.36%). The percentage of apoptotic cells in the bone marrow nucleated cells was 16.09%. The proportions of MDS clone in Annexin V(+)PI(-) and Annexin V(-)PI(-) cells were 32.48% and 70.11%, respectively. It is concluded that most myeloid and erythroid precursors are originated from the abnormal clone in MDS with del (20q). A little part of apoptotic cells are derived from the abnormal clone.

  18. Three distinct clones of carbapenem-resistant Acinetobacter baumannii with high diversity of carbapenemases isolated from patients in two hospitals in Kuwait

    Directory of Open Access Journals (Sweden)

    N.A. Al-Sweih

    2012-02-01

    Full Text Available Summary: Objectives: This study was undertaken to investigate the clonal relatedness of multidrug-resistant (MDR Acinetobacter baumannii isolates collected from patients in two teaching hospitals in Kuwait. Materials and methods: Clinically significant consecutive isolates of A. baumannii obtained from patients in the Mubarak (36 and Adan (58 hospitals over a period of 6 months were studied. These isolates were identified using molecular methods, and their antimicrobial susceptibility was determined by the Etest method. The mechanism of resistance to carbapenem was investigated by PCR, and pulsed-field gel electrophoresis (PFGE was used to determine the clonal relatedness of MDR isolates. Results: Of the 94 isolates investigated, 80 (85.1% were multidrug resistant (MDR. The A. baumannii PFGE clone A and subclone A1 were the most prevalent in patients infected with MDR isolates. Fifty-five (94.8% and 15 (41.7% of the MDR isolates from the Adan and Mubarak hospitals, respectively, belonged to PFGE clone A; isolates in this group showed higher resistance rates to antibiotics than isolates form other groups. Of the 94 isolates, 40 (42.6% were resistant to either imipenem or meropenem or to both (CRAB. Most CRAB isolates (29/40 or 72.5% carried bla genes, which code for MBL (VIM-2 and IMP-1 enzymes. Two isolates harbored blaOXA-23. Conclusion: Three distinct clones of CRAB were isolated, providing evidence of a high diversity of carbapenemases among our geographically related isolates. Keywords: MDR A. baumannii, Genotypes, bla genes, Kuwait hospitals

  19. Survival of irradiated glia and glioma cells studied with a new cloning technique

    International Nuclear Information System (INIS)

    Nilsson, S.; Carlsson, J.; Larsson, B.; Ponten, J.

    1980-01-01

    A method allowing cloning of monolayer cultured cells with a low plating efficiency was developed. Cells were grown in several small palladium squares to obtain a high cell density. These squares were surrounded by non-adhesive agarose to prevent large distance migration and thereby mixing of the clones. By using easily-cloned hamster cells for comparison it was found that the survival curves were similar to the curves obtained with conventional cloning. The new method was used to compare the radiosensitivity of cultured human glia and glioma cells which both have a low plating efficiency ( 0 -values (1.5 to 2.5 Gy) and large shoulders (extrapolation numbers around 5) indicating that they were rather resistant and had a high capacity for accumulation of sublethal damage. The survival curves for glia cells had lower D 0 -values (1.3 to 1.5 Gy) and no shoulders at all, indicating that they were more sensitive than the glioma cells. (author)

  20. Islet-specific T cell clones transfer diabetes to nonobese diabetic (NOD) F1 mice.

    Science.gov (United States)

    Peterson, J D; Pike, B; McDuffie, M; Haskins, K

    1994-09-15

    To investigate diabetes resistance to T cell-mediated disease transfer, we administered islet-specific T cell clones to the F1 progeny of nonobese diabetic (NOD) mice that were crossed with various nondiabetes-prone inbred mouse strains. We investigated four diabetogenic CD4+ T cell clones and all induced insulitis and full development of diabetes in (SWR x NOD)F1, (SJL x NOD)F1, and (C57BL/6 x NOD)F1 mice. In contrast, (BALB/c x NOD)F1 and (CBA x NOD)F1 mice were susceptible to disease transfer by some T cell clones but not others, and (C57/L x NOD)F1 mice seemed to be resistant to both insulitis and disease transfer by all of the clones tested. Disease induced by the T cell clones in susceptible F1 strains was age dependent and could only be observed in recipients younger than 13 days old. Full or partial disease resistance did not correlate with the presence or absence of I-E, different levels of Ag expression in islet cells, or differences in APC function. The results from this study suggest that there may be multiple factors contributing to susceptibility of F1 mice to T cell clone-mediated induction of diabetes, including non-MHC-related genetic background, the immunologic maturity of the recipient, and individual characteristics of the T cell clones.

  1. Isolation and characterization of dental epithelial cells derived from amelogenesis imperfecta rat.

    Science.gov (United States)

    Adiningrat, A; Tanimura, A; Miyoshi, K; Hagita, H; Yanuaryska, R D; Arinawati, D Y; Horiguchi, T; Noma, T

    2016-03-01

    Disruption of the third zinc finger domain of specificity protein 6 (SP6) presents an enamel-specific defect in a rat model of amelogenesis imperfecta (AMI rats). To understand the molecular basis of amelogenesis imperfecta caused by the Sp6 mutation, we established and characterized AMI-derived rat dental epithelial (ARE) cells. ARE cell clones were isolated from the mandibular incisors of AMI rats, and amelogenesis-related gene expression was analyzed by reverse transcription polymerase chain reaction (RT-PCR). Localization of wild-type SP6 (SP6WT) and mutant-type SP6 (SP6AMI) was analyzed by immunocytochemistry. SP6 transcriptional activity was monitored by rho-associated protein kinase 1 (Rock1) promoter activity with its specific binding to the promoter region in dental (G5 and ARE) and non-dental (COS-7) epithelial cells. Isolated ARE cells were varied in morphology and gene expression. Both SP6WT and SP6AMI were mainly detected in nuclei. The promoter analysis revealed that SP6WT and SP6AMI enhanced Rock1 promoter activity in G5 cells but that enhancement by SP6AMI was weaker, whereas no enhancement was observed in the ARE and COS-7 cells, even though SP6WT and SP6AMI bound to the promoter in all instances. ARE cell clones can provide a useful in vitro model to study the mechanism of SP6-mediated amelogenesis imperfecta. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  2. Isolation, cloning, and characterization of the 2S albumin: A new allergen from hazelnut

    NARCIS (Netherlands)

    Garino, Cristiano; Zuidmeer, Laurian; Marsh, Justin; Lovegrove, Alison; Morati, Maria; Versteeg, Serge; Schilte, Piet; Shewry, Peter; Arlorio, Marco; van Ree, Ronald

    2010-01-01

    Scope: 2S albumins are the major allergens involved in severe food allergy to nuts, seeds, and legumes. We aimed to isolate, clone, and express 2S albumin from hazelnut and determine its allergenicity. Methods: 2S albumin from hazelnut extract was purified using size exclusion chromatography and

  3. Preparation of Proper Immunogen by Cloning and Stable Expression of cDNA coding for Human Hematopoietic Stem Cell Marker CD34 in NIH-3T3 Mouse Fibroblast Cell Line

    Science.gov (United States)

    Shafaghat, Farzaneh; Abbasi-Kenarsari, Hajar; Majidi, Jafar; Movassaghpour, Ali Akbar; Shanehbandi, Dariush; Kazemi, Tohid

    2015-01-01

    Purpose: Transmembrane CD34 glycoprotein is the most important marker for identification, isolation and enumeration of hematopoietic stem cells (HSCs). We aimed in this study to clone the cDNA coding for human CD34 from KG1a cell line and stably express in mouse fibroblast cell line NIH-3T3. Such artificial cell line could be useful as proper immunogen for production of mouse monoclonal antibodies. Methods: CD34 cDNA was cloned from KG1a cell line after total RNA extraction and cDNA synthesis. Pfu DNA polymerase-amplified specific band was ligated to pGEMT-easy TA-cloning vector and sub-cloned in pCMV6-Neo expression vector. After transfection of NIH-3T3 cells using 3 μg of recombinant construct and 6 μl of JetPEI transfection reagent, stable expression was obtained by selection of cells by G418 antibiotic and confirmed by surface flow cytometry. Results: 1158 bp specific band was aligned completely to reference sequence in NCBI database corresponding to long isoform of human CD34. Transient and stable expression of human CD34 on transfected NIH-3T3 mouse fibroblast cells was achieved (25% and 95%, respectively) as shown by flow cytometry. Conclusion: Cloning and stable expression of human CD34 cDNA was successfully performed and validated by standard flow cytometric analysis. Due to murine origin of NIH-3T3 cell line, CD34-expressing NIH-3T3 cells could be useful as immunogen in production of diagnostic monoclonal antibodies against human CD34. This approach could bypass the need for purification of recombinant proteins produced in eukaryotic expression systems. PMID:25789221

  4. Successful cloning of coyotes through interspecies somatic cell nuclear transfer using domestic dog oocytes.

    Science.gov (United States)

    Hwang, Insung; Jeong, Yeon Woo; Kim, Joung Joo; Lee, Hyo Jeong; Kang, Mina; Park, Kang Bae; Park, Jung Hwan; Kim, Yeun Wook; Kim, Woo Tae; Shin, Taeyoung; Hyun, Sang Hwan; Jeung, Eui-Bae; Hwang, Woo Suk

    2013-01-01

    Interspecies somatic cell nuclear transfer (iSCNT) is an emerging assisted reproductive technology (ART) for preserving Nature's diversity. The scarcity of oocytes from some species makes utilisation of readily available oocytes inevitable. In the present study, we describe the successful cloning of coyotes (Canis latrans) through iSCNT using oocytes from domestic dogs (Canis lupus familiaris or dingo). Transfer of 320 interspecies-reconstructed embryos into 22 domestic dog recipients resulted in six pregnancies, from which eight viable offspring were delivered. Fusion rate and cloning efficiency during iSCNT cloning of coyotes were not significantly different from those observed during intraspecies cloning of domestic dogs. Using neonatal fibroblasts as donor cells significantly improved the cloning efficiency compared with cloning using adult fibroblast donor cells (Pcloning of coyotes in the present study holds promise for cloning other endangered species in the Canidae family using similar techniques. However, there are still limitations of the iSCNT technology, as demonstrated by births of morphologically abnormal coyotes and the clones' inheritance of maternal domestic dog mitochondrial DNA.

  5. Immunobiology of T cell responses to Mls-locus-disparate stimulator cells. III. Helper and cytolytic functions of cloned, Mls-reactive T cell lines

    International Nuclear Information System (INIS)

    Katz, M.E.; Tite, J.P.; Janeway, C.A. Jr.

    1986-01-01

    Mls-specific T cell clones derived by limiting dilution were tested for cytotoxic activity in a lectin-dependent 51 Cr-release assay. All the T cell clones tested were cytotoxic in such an assay in apparent contrast to previous reports (1, 2). However, only those target cells sensitive to cytolysis by other L3T4a + cytolytic T cells (3) were killed by Mls-specific T cell clones in short term 51 Cr-release assays, possibly explaining this discrepancy. All the T cell clones tested were L3T4a + ,Lyt-2 - and stimulated B cells from Mls strains of mice to proliferate and secrete immunoglobulin. Furthermore, lysis of innocent bystander targets was observed when the T cells were stimulated with Mls-disparate stimulator cells. These results are consistent with those obtained with L3T4a - T cells specific for protein antigen:self Ia and that express cytotoxic potential (3)

  6. Long term presence of a single predominant tyrosinase-specific T-cell clone associated with disease control in a patient with metastatic melanoma.

    Science.gov (United States)

    Ochsenreither, Sebastian; Fusi, Alberto; Busse, Antonia; Letsch, Anne; Haase, Doreen; Thiel, Eckhard; Scheibenbogen, Carmen; Keilholz, Ulrich

    2010-05-15

    In an earlier study, we described a patient who developed an anti-tyrosinase T-cell response leading to long-term tumor control. Here we analyzed this response with regard to T-cell receptor (TCR) Vbeta family usage and clonality in order to further elucidate the nature of the T cell response in this patient. For identification of expanded specific cytotoxic T-cell (CTL) clones, tetramer enrichment of tyrosinase reactive T-cells was followed by comparative quantitative reverse transcribed PCR (qRT PCR) quantification of all TCR Vbeta-families and sequencing of family Vbeta4 elevated in the enriched fraction. The predominant specific clone was quantified by clonotypic qRT PCR in multiple samples from blood, bone marrow, and tumor tissue. FACS analyses with staining of TYR.A2 and TCR Vbeta4 were performed. Epitope specific enrichment revealed an isolated increase of Vbeta-family 4. FACS analysis showed a shift of specific CTLs to Vbeta-family 4 during tumor regression with a maximum of 80% of all TYR.A2 specific cells belonging to this family. Sequencing revealed a single predominant clone against polyclonal background coding for identical CDR3 loops. The predominant clone was highly expressed in bone marrow and tumor tissue, and was detectable in blood over a period of ten years. Considering the results of previous studies showing a specific effector phenotype in blood and a specific memory compartment in bone marrow of this patient, this data implicate the predominant clone featured all attributes of a sufficient CTL response including homing capacity and memory formation resulting in long term clonal persistence and tumor control.

  7. Glucocorticoids inhibit the proliferation of IL-2-dependent T cell clones

    International Nuclear Information System (INIS)

    Fresno, M.; Redondo, J.M.; Lopez-Rivas, A.

    1986-01-01

    It has been shown that glucocorticoids inhibit mitogen or antigen-induced lymphocyte proliferation by decreasing the production of interleukin-2 (IL-2). They have studied the effect of dexamethasone (Dx) on the proliferation of IL-2-dependent T cell clones. They have found that preincubation of these clones with Dx inhibits ( 3 H) thymidine incorporation and cell proliferation in a dose-dependent manner (ID 50 % 5 x 10 -10 M). The inhibition of DNA synthesis by Dx was dependent on the concentration of IL-2. High concentration of IL-2 reversed completely this inhibition. The action of Dx seems to be mediated through the induction of a protein since the simultaneous presence of cycloheximide and Dx prevented the inhibitory effect of the latter. Moreover, dialyzed conditioned medium of Dx treated cells inhibited DNA synthesis by T cell clones. The biochemical characterization of this protein is in progress

  8. Human therapeutic cloning (NTSC): applying research from mammalian reproductive cloning.

    Science.gov (United States)

    French, Andrew J; Wood, Samuel H; Trounson, Alan O

    2006-01-01

    Human therapeutic cloning or nuclear transfer stem cells (NTSC) to produce patient-specific stem cells, holds considerable promise in the field of regenerative medicine. The recent withdrawal of the only scientific publications claiming the successful generation of NTSC lines afford an opportunity to review the available research in mammalian reproductive somatic cell nuclear transfer (SCNT) with the goal of progressing human NTSC. The process of SCNT is prone to epigenetic abnormalities that contribute to very low success rates. Although there are high mortality rates in some species of cloned animals, most surviving clones have been shown to have normal phenotypic and physiological characteristics and to produce healthy offspring. This technology has been applied to an increasing number of mammals for utility in research, agriculture, conservation, and biomedicine. In contrast, attempts at SCNT to produce human embryonic stem cells (hESCs) have been disappointing. Only one group has published reliable evidence of success in deriving a cloned human blastocyst, using an undifferentiated hESC donor cell, and it failed to develop into a hESC line. When optimal conditions are present, it appears that in vitro development of cloned and parthenogenetic embryos, both of which may be utilized to produce hESCs, may be similar to in vitro fertilized embryos. The derivation of ESC lines from cloned embryos is substantially more efficient than the production of viable offspring. This review summarizes developments in mammalian reproductive cloning, cell-to-cell fusion alternatives, and strategies for oocyte procurement that may provide important clues facilitating progress in human therapeutic cloning leading to the successful application of cell-based therapies utilizing autologous hESC lines.

  9. Evidence for association of the cloned liver growth hormone receptor with a tyrosine kinase

    DEFF Research Database (Denmark)

    Wang, X; Uhler, M D; Billestrup, N

    1992-01-01

    The ability of the cloned liver growth hormone (GH) receptor, when expressed in mammalian cell lines, to copurify with tyrosine kinase activity and be tyrosyl phosphorylated was examined. 125I-human growth hormone-GH receptor complexes isolated from COS-7 cells transiently expressing high levels...... of tyrosine kinase activity with cloned liver GH receptor. The level of phosphorylation of the GH receptor was very low, as compared with the endogenous GH receptor in 3T3-F442A cells, suggesting that tyrosine kinase activity is not intrinsic to the cloned GH receptor but rather resides with a kinase present...... in a variety of cell types. The finding that the level of phosphorylation of GH receptor appears to vary with cell type is consistent with the cloned liver GH receptor being a substrate for an associated tyrosine kinase and with the amount of such a GH receptor-associated tyrosine kinase being cell type-specific....

  10. Isolation and sequence analysis of a cDNA clone encoding the fifth complement component

    DEFF Research Database (Denmark)

    Lundwall, Åke B; Wetsel, Rick A; Kristensen, Torsten

    1985-01-01

    DNA clone of 1.85 kilobase pairs was isolated. Hybridization of the mixed-sequence probe to the complementary strand of the plasmid insert and sequence analysis by the dideoxy method predicted the expected protein sequence of C5a (positions 1-12), amino-terminal to the anticipated priming site. The sequence......, subcloned into M13 mp8, and sequenced at random by the dideoxy technique, thereby generating a contiguous sequence of 1703 base pairs. This clone contained coding sequence for the C-terminal 262 amino acid residues of the beta-chain, the entire C5a fragment, and the N-terminal 98 residues of the alpha......'-chain. The 3' end of the clone had a polyadenylated tail preceded by a polyadenylation recognition site, a 3'-untranslated region, and base pairs homologous to the human Alu concensus sequence. Comparison of the derived partial human C5 protein sequence with that previously determined for murine C3 and human...

  11. Genetic subclone architecture of tumor clone-initiating cells in colorectal cancer.

    Science.gov (United States)

    Giessler, Klara M; Kleinheinz, Kortine; Huebschmann, Daniel; Balasubramanian, Gnana Prakash; Dubash, Taronish D; Dieter, Sebastian M; Siegl, Christine; Herbst, Friederike; Weber, Sarah; Hoffmann, Christopher M; Fronza, Raffaele; Buchhalter, Ivo; Paramasivam, Nagarajan; Eils, Roland; Schmidt, Manfred; von Kalle, Christof; Schneider, Martin; Ulrich, Alexis; Scholl, Claudia; Fröhling, Stefan; Weichert, Wilko; Brors, Benedikt; Schlesner, Matthias; Ball, Claudia R; Glimm, Hanno

    2017-07-03

    A hierarchically organized cell compartment drives colorectal cancer (CRC) progression. Genetic barcoding allows monitoring of the clonal output of tumorigenic cells without prospective isolation. In this study, we asked whether tumor clone-initiating cells (TcICs) were genetically heterogeneous and whether differences in self-renewal and activation reflected differential kinetics among individual subclones or functional hierarchies within subclones. Monitoring genomic subclone kinetics in three patient tumors and corresponding serial xenografts and spheroids by high-coverage whole-genome sequencing, clustering of genetic aberrations, subclone combinatorics, and mutational signature analysis revealed at least two to four genetic subclones per sample. Long-term growth in serial xenografts and spheroids was driven by multiple genomic subclones with profoundly differing growth dynamics and hence different quantitative contributions over time. Strikingly, genetic barcoding demonstrated stable functional heterogeneity of CRC TcICs during serial xenografting despite near-complete changes in genomic subclone contribution. This demonstrates that functional heterogeneity is, at least frequently, present within genomic subclones and independent of mutational subclone differences. © 2017 Giessler et al.

  12. Keith's MAGIC: Cloning and the Cell Cycle.

    Science.gov (United States)

    Wells, D N

    2013-10-01

    Abstract Professor Keith Campbell's critical contribution to the discovery that a somatic cell from an adult animal can be fully reprogrammed by oocyte factors to form a cloned individual following nuclear transfer (NT)(Wilmut et al., 1997 ) overturned a dogma concerning the reversibility of cell fate that many scientists had considered to be biologically impossible. This seminal experiment proved the totipotency of adult somatic nuclei and finally confirmed that adult cells could differentiate without irreversible changes to the genetic material.

  13. Differences in genotype and virulence among four multidrug-resistant Streptococcus pneumoniae isolates belonging to the PMEN1 clone.

    Directory of Open Access Journals (Sweden)

    N Luisa Hiller

    Full Text Available We report on the comparative genomics and characterization of the virulence phenotypes of four S. pneumoniae strains that belong to the multidrug resistant clone PMEN1 (Spain(23F ST81. Strains SV35-T23 and SV36-T3 were recovered in 1996 from the nasopharynx of patients at an AIDS hospice in New York. Strain SV36-T3 expressed capsule type 3 which is unusual for this clone and represents the product of an in vivo capsular switch event. A third PMEN1 isolate - PN4595-T23 - was recovered in 1996 from the nasopharynx of a child attending day care in Portugal, and a fourth strain - ATCC700669 - was originally isolated from a patient with pneumococcal disease in Spain in 1984. We compared the genomes among four PMEN1 strains and 47 previously sequenced pneumococcal isolates for gene possession differences and allelic variations within core genes. In contrast to the 47 strains - representing a variety of clonal types - the four PMEN1 strains grouped closely together, demonstrating high genomic conservation within this lineage relative to the rest of the species. In the four PMEN1 strains allelic and gene possession differences were clustered into 18 genomic regions including the capsule, the blp bacteriocins, erythromycin resistance, the MM1-2008 prophage and multiple cell wall anchored proteins. In spite of their genomic similarity, the high resolution chinchilla model was able to detect variations in virulence properties of the PMEN1 strains highlighting how small genic or allelic variation can lead to significant changes in pathogenicity and making this set of strains ideal for the identification of novel virulence determinants.

  14. In vitro properties and tumorigenicity of radiation-transformed clones of mouse 10T1/2 cells

    International Nuclear Information System (INIS)

    Otsu, Hiroshi; Yasukawa, Mieko; Terasima, Toyozo

    1983-01-01

    Nineteen radiation-induced and one spontaneously developed transformed foci were cloned from mouse 10T1/2 cells. Each clone was grown with normal 10T1/2 cells, and typing (types II and III) was carried out by making reference to the description of Reznikoff et al. Morphological characteristics of foci and their response to co-cultured normal counterparts are described. Some in vitro properties of the clones were examined and the relationship to each focus type is discussed. A reduced serum requirement of transformed clones was not recognized. Soft agar colonies were produced exclusively by type III clones. Tumorigenicity testing of the clones revealed that 93 % of type III clones were tumorigenic upon inoculation into syngeneic mice in an immunosuppressed condition. From these findings, it can be concluded that the tumorigenic potential of radiation-induced transformed cells can be predicted from the ability of the cells to form colonies in agar. (author)

  15. Spontaneous mutation rate in Chinese hamster cell clones differing in UV-sensitivity

    International Nuclear Information System (INIS)

    Manuilova, E.S.; Bagrova, A.M.; Moskovskij Gosudarstvennyj Univ.

    1983-01-01

    The spontaneous rate of appearance of mutations to 6-mercaptopurine (6 MP) resistence in the cells of CHR2 and CHs2 clones dofferent in sensitivity to lethal and matagenous effect of UV-rays, is investigated. Increased UV-sensitivity of CHs2 clone is caused by the violation of postreplicative DNA reparation. It is established that the purity of spontaneously occuring mutations in both clones turns out to be similar, i.e. (1.5-1.8)x10 -5 for the cell pergeneration. It is shown that the effect of postreplicative DNA reparation in the cells of chinese hamster is not connected with the increase of spontaneous mutation ability. The problem on the possible role of reparation in the mechanism of appearance of spontaneous and induced mutations in the cells of Chinese hamster with increased UV-sensitivity is discussed

  16. Isolation and cloning of a metalloproteinase from king cobra snake venom.

    Science.gov (United States)

    Guo, Xiao-Xi; Zeng, Lin; Lee, Wen-Hui; Zhang, Yun; Jin, Yang

    2007-06-01

    A 50 kDa fibrinogenolytic protease, ohagin, from the venom of Ophiophagus hannah was isolated by a combination of gel filtration, ion-exchange and heparin affinity chromatography. Ohagin specifically degraded the alpha-chain of human fibrinogen and the proteolytic activity was completely abolished by EDTA, but not by PMSF, suggesting it is a metalloproteinase. It dose-dependently inhibited platelet aggregation induced by ADP, TMVA and stejnulxin. The full sequence of ohagin was deduced by cDNA cloning and confirmed by protein sequencing and peptide mass fingerprinting. The full-length cDNA sequence of ohagin encodes an open reading frame of 611 amino acids that includes signal peptide, proprotein and mature protein comprising metalloproteinase, disintegrin-like and cysteine-rich domains, suggesting it belongs to P-III class metalloproteinase. In addition, P-III class metalloproteinases from the venom glands of Naja atra, Bungarus multicinctus and Bungarus fasciatus were also cloned in this study. Sequence analysis and phylogenetic analysis indicated that metalloproteinases from elapid snake venoms form a new subgroup of P-III SVMPs.

  17. Characterization of cloned cells from an immortalized fetal pulmonary type II cell line

    Energy Technology Data Exchange (ETDEWEB)

    Henderson, R.F.; Waide, J.J.; Lechner, J.F.

    1995-12-01

    A cultured cell line that maintained expression of pulmonary type II cell markers of differentiation would be advantageous to generate a large number of homogenous cells in which to study the biochemical functions of type II cells. Type II epithelial cells are the source of pulmonary surfactant and a cell of origin for pulmonary adenomas. Last year our laboratory reported the induction of expression of two phenotypic markers of pulmonary type II cells (alkaline phosphatase activity and surfactant lipid synthesis) in cultured fetal rat lung epithelial (FRLE) cells, a spontaneously immortalized cell line of fetal rat lung type II cell origin. Subsequently, the induction of the ability to synthesize surfactant lipid became difficult to repeat. We hypothesized that the cell line was heterogenuous and some cells were more like type II cells than others. The purpose of this study was to test this hypothesis and to obtain a cultured cell line with type II cell phenotypic markers by cloning several FRLE cells and characterizing them for phenotypic markers of type II cells (alkaline phosphatase activity and presence of surfactant lipids). Thirty cloned cell lines were analyzed for induced alkaline phosphatase activity (on x-axis) and for percent of phospholipids that were disaturated (i.e., surfactant).

  18. Bengal Bay clone ST772-MRSA-V outbreak: conserved clone causes investigation challenges.

    Science.gov (United States)

    Blomfeldt, A; Larssen, K W; Moghen, A; Haugum, K; Steen, T W; Jørgensen, S B; Aamot, H V

    2017-03-01

    The Bengal Bay clone, ST772-MRSA-V, associated with multi-drug resistance, Panton-Valentine leukocidin (PVL) and skin and soft tissue infections, is emerging worldwide. In Norway, a country with low prevalence of meticillin-resistant Staphylococcus aureus (MRSA), increased occurrence of ST772-MRSA-V has also caused hospital outbreaks. The conserved nature of this clone challenged the outbreak investigations. To evaluate the usefulness of S. aureus protein A (spa) typing, multiple-locus variable number tandem repeat fingerprinting/analysis (MLVF/MLVA) and pulsed-field gel electrophoresis (PFGE) when investigating outbreaks with a conserved MRSA clone. A panel of 25 MRSA isolates collected in 2004-2014, consisting of six hospital outbreak isolates and 19 sporadic isolates, were analysed using spa typing, polymerase chain reaction detection of genes encoding PVL, MLVF/MLVA and PFGE. All isolates were ST772-MRSA-V-t657 and resistant to erythromycin, gentamicin and norfloxacin, and 88% were PVL positive. PFGE could not discriminate between the isolates (≥85% similarity). MLVF resolved five types [Simpson's index of diversity (SID)=0.56], MLVA resolved six types (SID=0.66), and both methods separated the hospital isolates into two defined outbreaks. MLVF/MLVA could not discriminate all epidemiologically unlinked cases and identical genotypes originated from a timespan of 10 years. MLVA was regarded as most suitable due to its higher discriminatory power and ability to provide unambiguous profiles. However, the Bengal Bay clone may require higher resolution methods for exact demarcation of outbreaks due to low diversity among isolates. Copyright © 2016 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  19. Improvement of mouse cloning using nuclear transfer-derived embryonic stem cells and/or histone deacetylase inhibitor.

    Science.gov (United States)

    Wakayama, Sayaka; Wakayama, Teruhiko

    2010-01-01

    Nuclear transfer-derived ES (ntES) cell lines can be established from somatic cell nuclei with a relatively high success rate. Although ntES cells have been shown to be equivalent to ES cells, there are ethical objections concerning human cells, such as the use of fresh oocyte donation from young healthy woman. In contrast, the use of induced pluripotent stem (iPS) cells for cloning poses few ethical problems and is a relatively easy technique compared with nuclear transfer. Therefore, although there are several reports proposing the use of ntES cells as a model of regenerative medicine, the use of these cells in preliminary medical research is waning. However, in theory, 5 to 10 donor cells can establish one ntES cell line and, once established, these cells will propagate indefinitely. These cells can be used to generate cloned animals from ntES cell lines using a second round of NT. Even in infertile and "unclonable" strains of mice, we can generate offspring from somatic cells by combining cloning with ntES technology. Moreover, cloned offspring can be generated potentially even from the nuclei of dead bodies or freeze-dried cells via ntES cells, such as from an extinct frozen animal. Currently, only the ntES technology is available for this purpose, because all other techniques, including iPS cell derivation, require significant numbers of living donor cells. This review describes how to improve the efficiency of cloning, the establishment of clone-derived embryonic stem cells and further applications.

  20. Human Endothelial Cells: Use of Heparin in Cloning and Long-Term Serial Cultivation

    Science.gov (United States)

    Thornton, Susan C.; Mueller, Stephen N.; Levine, Elliot M.

    1983-11-01

    Endothelial cells from human blood vessels were cultured in vitro, with doubling times of 17 to 21 hours for 42 to 79 population doublings. Cloned human endothelial cell strains were established for the first time and had similar proliferative capacities. This vigorous cell growth was achieved by addition of heparin to culture medium containing reduced concentrations of endothelial cell growth factor. The routine cloning and long-term culture of human endothelial cells will facilitate studying the human endothelium in vitro.

  1. Cortactin and phagocytosis in isolated Sertoli cells

    Directory of Open Access Journals (Sweden)

    Wolski Katja M

    2005-12-01

    Full Text Available Abstract Background Cortactin, an actin binding protein, has been associated with Sertoli cell ectoplasmic specializations in vivo, based on its immunolocalization around the heads of elongated spermatids, but not previously identified in isolated Sertoli cells. In an in vitro model of Sertoli cell-spermatid binding, cortactin was identified around debris and dead germ cells. Based on this observation, we hypothesized that this actin binding protein may be associated with a non-junction-related physiological function, such as phagocytosis. The purpose of this study was to identify the presence and distribution of cortactin in isolated rat Sertoli cells active in phagocytic activity following the addition of 0.8 μm latex beads. Results Sertoli cell monocultures were incubated with or without follicle stimulating hormone (FSH; 0.1 μg/ml in the presence or absence of cytochalasin D (2 μM, as an actin disrupter. Cortactin was identified by standard immunostaining with anti-cortactin, clone 4F11 (Upstate after incubation times of 15 min, 2 hr, and 24 hr with or without beads. Cells exposed to no hormone and no beads appeared to have a ubiquitous distribution of cortactin throughout the cytoplasm. In the presence of cytochalasin D, cortactin immunostaining was punctate and distributed in a pattern similar to that reported for actin in cells exposed to cytochalasin D. Sertoli cells not exposed to FSH, but activated with beads, did not show cortactin immunostaining around the phagocytized beads at any of the time periods. FSH exposure did not alter the distribution of cortactin within Sertoli cells, even when phagocytic activity was upregulated by the presence of beads. Conclusion Results of this study suggest cortactin is not associated with peripheralized actin at junctional or phagocytic sites. Further studies are necessary to clarify the role of cortactin in Sertoli cells.

  2. Evaluation of cloned cells, animal model, and ATRA sensitivity of human testicular yolk sac tumor

    Directory of Open Access Journals (Sweden)

    Zhao Junfeng

    2012-03-01

    Full Text Available Abstract The testicular yolk sac tumor (TYST is the most common neoplasm originated from germ cells differentiated abnormally, a major part of pediatric malignant testicular tumors. The present study aimed at developing and validating the in vitro and vivo models of TYST and evaluating the sensitivity of TYST to treatments, by cloning human TYST cells and investigating the histology, ultra-structure, growth kinetics and expression of specific proteins of cloned cells. We found biological characteristics of cloned TYST cells were similar to the yolk sac tumor and differentiated from the columnar to glandular-like or goblet cells-like cells. Chromosomes for tumor identification in each passage met nature of the primary tumor. TYST cells were more sensitive to all-trans-retinoic acid which had significantly inhibitory effects on cell proliferation. Cisplatin induced apoptosis of TYST cells through the activation of p53 expression and down-regulation of Bcl- expression. Thus, we believe that cloned TYST cells and the animal model developed here are useful to understand the molecular mechanism of TYST cells and develop potential therapies for human TYST.

  3. Nuclear donor cell lines considerably influence cloning efficiency and the incidence of large offspring syndrome in bovine somatic cell nuclear transfer.

    Science.gov (United States)

    Liu, J; Wang, Y; Su, J; Luo, Y; Quan, F; Zhang, Y

    2013-08-01

    Total five ear skin fibroblast lines (named F1, F2, F3, F4 and F5) from different newborn Holstein cows have been used as nuclear donor cells for producing cloned cows by somatic cell nuclear transfer (SCNT). The effects of these cell lines on both in vitro and in vivo developmental rates of cloned embryos, post-natal survivability and incidence of large offspring syndrome (LOS) were examined in this study. We found that the different cell lines possessed the same capacity to support pre-implantation development of cloned embryos, the cleavage and blastocyst formation rates ranged from 80.2 ± 0.9 to 84.5 ± 2.5% and 28.5 ± 0.9 to 33.3 ± 1.4%, respectively. However, their capacities to support the in vivo development of SCNT embryos showed significant differences (p cloning efficiency was significantly higher in group F5 than those in group F1, F2, F3 and F4 (9.3% vs 4.1%, 1.2%, 2.0% and 5.0%, respectively, p cloned offspring from cell line F1, F2, F3 and F4 showed LOS and gestation length delay, while all cloned offspring from F5 showed normal birthweight and gestation length. We concluded that the nuclear donor cell lines have significant impact on the in vivo development of cloned embryos and the incidence of LOS in cloned calves. © 2013 Blackwell Verlag GmbH.

  4. [Cloning of human CD45 gene and its expression in Hela cells].

    Science.gov (United States)

    Li, Jie; Xu, Tianyu; Wu, Lulin; Zhang, Liyun; Lu, Xiao; Zuo, Daming; Chen, Zhengliang

    2015-11-01

    To clone human CD45 gene PTPRC and establish Hela cells overexpressing recombinant human CD45 protein. The intact cDNA encoding human CD45 amplified using RT-PCR from the total RNA extracted from peripheral blood mononuclear cells (PBMCs) of a healthy donor was cloned into pMD-18T vector. The CD45 cDNA fragment amplified from the pMD-18T-CD45 by PCR was inserted to the coding region of the PcDNA3.1-3xflag vector, and the resultant recombinant expression vector PcDNA3.1-3xflag-CD45 was transfected into Hela cells. The expression of CD45 in Hela cells was detected by flow cytometry and Western blotting, and the phosphastase activity of CD45 was quantified using an alkaline phosphatase assay kit. The cDNA fragment of about 3 900 bp was amplified from human PBMCs and cloned into pMD-18T vector. The recombinant expression vector PcDNA3.1-3xflag-CD45 was constructed, whose restriction maps and sequence were consistent with those expected. The expression of CD45 in transfected Hela cells was detected by flow cytometry and Western blotting, and the expressed recombinant CD45 protein in Hela cells showed a phosphastase activity. The cDNA of human CD45 was successfully cloned and effectively expressed in Hela cells, which provides a basis for further exploration of the functions of CD45.

  5. Inference of Cell Mechanics in Heterogeneous Epithelial Tissue Based on Multivariate Clone Shape Quantification

    Science.gov (United States)

    Tsuboi, Alice; Umetsu, Daiki; Kuranaga, Erina; Fujimoto, Koichi

    2017-01-01

    Cell populations in multicellular organisms show genetic and non-genetic heterogeneity, even in undifferentiated tissues of multipotent cells during development and tumorigenesis. The heterogeneity causes difference of mechanical properties, such as, cell bond tension or adhesion, at the cell–cell interface, which determine the shape of clonal population boundaries via cell sorting or mixing. The boundary shape could alter the degree of cell–cell contacts and thus influence the physiological consequences of sorting or mixing at the boundary (e.g., tumor suppression or progression), suggesting that the cell mechanics could help clarify the physiology of heterogeneous tissues. While precise inference of mechanical tension loaded at each cell–cell contacts has been extensively developed, there has been little progress on how to distinguish the population-boundary geometry and identify the cause of geometry in heterogeneous tissues. We developed a pipeline by combining multivariate analysis of clone shape with tissue mechanical simulations. We examined clones with four different genotypes within Drosophila wing imaginal discs: wild-type, tartan (trn) overexpression, hibris (hbs) overexpression, and Eph RNAi. Although the clones were previously known to exhibit smoothed or convoluted morphologies, their mechanical properties were unknown. By applying a multivariate analysis to multiple criteria used to quantify the clone shapes based on individual cell shapes, we found the optimal criteria to distinguish not only among the four genotypes, but also non-genetic heterogeneity from genetic one. The efficient segregation of clone shape enabled us to quantitatively compare experimental data with tissue mechanical simulations. As a result, we identified the mechanical basis contributed to clone shape of distinct genotypes. The present pipeline will promote the understanding of the functions of mechanical interactions in heterogeneous tissue in a non-invasive manner. PMID

  6. GLUT3 is present in Clone 9 liver cells and translocates to the plasma membrane in response to insulin.

    Science.gov (United States)

    Defries, Danielle M; Taylor, Carla G; Zahradka, Peter

    2016-08-26

    Clone 9 cells have been reported to express only the GLUT1 facilitative glucose transporter; however, previous studies have not examined Clone 9 cells for GLUT3 content. The current study sought to profile the presence of glucose transporters in Clone 9 cells, H4IIE hepatoma cells, and L6 myoblasts and myotubes. While the other cell types contained the expected complement of transporters, Clone 9 cells had GLUT3 which was previously not reported. Interestingly, both GLUT3 mRNA and protein were detected in Clone 9 cells, but only mRNA for GLUT1 was detected. Glucose transport in Clone 9 cells was insulin-sensitive in a concentration-dependent manner, concomitant with the presence of GLUT3 in the plasma membrane after insulin treatment. Although basal glucose uptake was unaffected, insulin-stimulated glucose uptake was abolished with siRNA-mediated GLUT3 knockdown. These results contradict previous reports that Clone 9 cells exclusively express GLUT1 and suggest GLUT3 is a key insulin-sensitive glucose transporter required for insulin-stimulated glucose uptake by Clone 9 cells. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Handmade Cloned Buffalo (Bubalus bubalis) Embryos Produced from Somatic Cells Isolated from Milk and Ear Skin Differ in Their Developmental Competence, Epigenetic Status, and Gene Expression.

    Science.gov (United States)

    Jyotsana, Basanti; Sahare, Amol A; Raja, Anuj K; Singh, Karn P; Singla, Suresh K; Chauhan, Manmohan S; Manik, Radhey S; Palta, Prabhat

    2015-10-01

    We compared the cloning efficiency of buffalo embryos produced by handmade cloning (HMC) using ear skin- and milk-derived donor cells. The blastocyst rate was lower (p  milk-derived blastocysts and that of NANOG was (p  milk-derived > skin-derived blastocysts. The expression level of all these genes, except NANOG, was lower (p < 0.05) in milk- than in skin-derived or IVF blastocysts. In conclusion, milk-derived cells can be used for producing HMC embryos of quality similar to that of skin-derived embryos, although with a lower blastocyst rate.

  8. Automatic cell cloning assay for determining the clonogenic capacity of cancer and cancer stem-like cells.

    Science.gov (United States)

    Fedr, Radek; Pernicová, Zuzana; Slabáková, Eva; Straková, Nicol; Bouchal, Jan; Grepl, Michal; Kozubík, Alois; Souček, Karel

    2013-05-01

    The clonogenic assay is a well-established in vitro method for testing the survival and proliferative capability of cells. It can be used to determine the cytotoxic effects of various treatments including chemotherapeutics and ionizing radiation. However, this approach can also characterize cells with different phenotypes and biological properties, such as stem cells or cancer stem cells. In this study, we implemented a faster and more precise method for assessing the cloning efficiency of cancer stem-like cells that were characterized and separated using a high-speed cell sorter. Cell plating onto a microplate using an automatic cell deposition unit was performed in a single-cell or dilution rank mode by the fluorescence-activated cell sorting method. We tested the new automatic cell-cloning assay (ACCA) on selected cancer cell lines and compared it with the manual approach. The obtained results were also compared with the results of the limiting dilution assay for different cell lines. We applied the ACCA to analyze the cloning capacity of different subpopulations of prostate and colon cancer cells based on the expression of the characteristic markers of stem (CD44 and CD133) and cancer stem cells (TROP-2, CD49f, and CD44). Our results revealed that the novel ACCA is a straightforward approach for determining the clonogenic capacity of cancer stem-like cells identified in both cell lines and patient samples. Copyright © 2013 International Society for Advancement of Cytometry.

  9. Mitochondrial DNA heteroplasmy in ovine fetuses and sheep cloned by somatic cell nuclear transfer

    Directory of Open Access Journals (Sweden)

    Müller Mathias

    2007-12-01

    Full Text Available Abstract Background The mitochondrial DNA (mtDNA of the cloned sheep "Dolly" and nine other ovine clones produced by somatic cell nuclear transfer (SCNT was reported to consist only of recipient oocyte mtDNA without any detectable mtDNA contribution from the nucleus donor cell. In cattle, mouse and pig several or most of the clones showed transmission of nuclear donor mtDNA resulting in mitochondrial heteroplasmy. To clarify the discrepant transmission pattern of donor mtDNA in sheep clones we analysed the mtDNA composition of seven fetuses and five lambs cloned from fetal fibroblasts. Results The three fetal fibroblast donor cells used for SCNT harboured low mtDNA copy numbers per cell (A: 753 ± 54, B: 292 ± 33 and C: 561 ± 88. The ratio of donor to recipient oocyte mtDNAs was determined using a quantitative amplification refractory mutation system (ARMS PCR (i.e. ARMS-qPCR. For quantification of SNP variants with frequencies below 0.1% we developed a restriction endonuclease-mediated selective quantitative PCR (REMS-qPCR. We report the first cases (n = 4 fetuses, n = 3 lambs of recipient oocyte/nuclear donor mtDNA heteroplasmy in SCNT-derived ovine clones demonstrating that there is no species-effect hindering ovine nucleus-donor mtDNA from being transmitted to the somatic clonal offspring. Most of the heteroplasmic clones exhibited low-level heteroplasmy (0.1% to 0.9%, n = 6 indicating neutral transmission of parental mtDNAs. High-level heteroplasmy (6.8% to 46.5% was observed in one case. This clone possessed a divergent recipient oocyte-derived mtDNA genotype with three rare amino acid changes compared to the donor including one substitution at an evolutionary conserved site. Conclusion Our study using state-of-the-art techniques for mtDNA quantification, like ARMS-qPCR and the novel REMS-qPCR, documents for the first time the transmission of donor mtDNA into somatic sheep clones. MtDNA heteroplasmy was detected in seven of 12 clones

  10. Cloning and characterization of the major histone H2A genes completes the cloning and sequencing of known histone genes of Tetrahymena thermophila.

    Science.gov (United States)

    Liu, X; Gorovsky, M A

    1996-01-01

    A truncated cDNA clone encoding Tetrahymena thermophila histone H2A2 was isolated using synthetic degenerate oligonucleotide probes derived from H2A protein sequences of Tetrahymena pyriformis. The cDNA clone was used as a homologous probe to isolate a truncated genomic clone encoding H2A1. The remaining regions of the genes for H2A1 (HTA1) and H2A2 (HTA2) were then isolated using inverse PCR on circularized genomic DNA fragments. These partial clones were assembled into intact HTA1 and HTA2 clones. Nucleotide sequences of the two genes were highly homologous within the coding region but not in the noncoding regions. Comparison of the deduced amino acid sequences with protein sequences of T. pyriformis H2As showed only two and three differences respectively, in a total of 137 amino acids for H2A1, and 132 amino acids for H2A2, indicating the two genes arose before the divergence of these two species. The HTA2 gene contains a TAA triplet within the coding region, encoding a glutamine residue. In contrast with the T. thermophila HHO and HTA3 genes, no introns were identified within the two genes. The 5'- and 3'-ends of the histone H2A mRNAs; were determined by RNase protection and by PCR mapping using RACE and RLM-RACE methods. Both genes encode polyadenylated mRNAs and are highly expressed in vegetatively growing cells but only weakly expressed in starved cultures. With the inclusion of these two genes, T. thermophila is the first organism whose entire complement of known core and linker histones, including replication-dependent and basal variants, has been cloned and sequenced. PMID:8760889

  11. Molecular cloning of complementary DNAs encoding the heavy chain of the human 4F2 cell-surface antigen: a type II membrane glycoprotein involved in normal and neoplastic cell growth

    International Nuclear Information System (INIS)

    Quackenbush, E.; Clabby, M.; Gottesdiener, K.M.; Barbosa, J.; Jones, N.H.; Strominger, J.L.; Speck, S.; Leiden, J.M.

    1987-01-01

    Complementary DNA (cDNA) clones encoding the heavy chain of the heterodimeric human membrane glycoprotein 4F2 have been isolated by immunoscreening of a λgt11 expression library. The identity of these clones has been confirmed by hybridization to RNA and DNA prepared from mouse L-cell transfectants, which were produced by whole cell gene transfer and selected for cell-surface expression of the human 4F2 heavy chain. DNA sequence analysis suggest that the 4F2 heavy-chain cDNAs encode an approximately 526-amino acid type II membrane glycoprotein, which is composed of a large C-terminal extracellular domain, a single potential transmembrane region, and a 50-81 amino acid N-terminal intracytoplasmic domain. Southern blotting experiments have shown that the 4F2 heavy-chain cDNAs are derived from a single-copy gene that has been highly conserved during mammalian evolution

  12. Primer sets for cloning the human repertoire of T cell Receptor Variable regions.

    Science.gov (United States)

    Boria, Ilenia; Cotella, Diego; Dianzani, Irma; Santoro, Claudio; Sblattero, Daniele

    2008-08-29

    Amplification and cloning of naïve T cell Receptor (TR) repertoires or antigen-specific TR is crucial to shape immune response and to develop immuno-based therapies. TR variable (V) regions are encoded by several genes that recombine during T cell development. The cloning of expressed genes as large diverse libraries from natural sources relies upon the availability of primers able to amplify as many V genes as possible. Here, we present a list of primers computationally designed on all functional TR V and J genes listed in the IMGT, the ImMunoGeneTics information system. The list consists of unambiguous or degenerate primers suitable to theoretically amplify and clone the entire TR repertoire. We show that it is possible to selectively amplify and clone expressed TR V genes in one single RT-PCR step and from as little as 1000 cells. This new primer set will facilitate the creation of more diverse TR libraries than has been possible using currently available primer sets.

  13. Human cloning. Fact or fiction

    International Nuclear Information System (INIS)

    Abushama, Mandy D.; Ahmed, Badreldeen I.

    2003-01-01

    Cloning is the production of one or more individual plants or animals that are genetically identical to other plant, animal or human. Scientists even demonstrated that they were able to clone frog tadpoles from frog embryonic cells using nuclear transfer.Many animals have been cloned from adult cells using nuclear transfer. Somatic cell nuclear transfer which refers to the transfer of the nucleous from a somatic cell to an egg cell. Article further deals with benefits and misuses of human cloning

  14. Health status and productive performance of somatic cell cloned cattle and their offspring produced in Japan.

    Science.gov (United States)

    Watanabe, Shinya; Nagai, Takashi

    2008-02-01

    Since the first somatic cell cloned calves were born in Japan in 1998, more than 500 cloned cattle have been produced by somatic cell nuclear transfer and many studies concerning cloned cattle and their offspring have been conducted in this country. However, most of the results have been published in Japanese; thus, the data produced in this country is not well utilized by researchers throughout the world. This article reviews the 65 reports produced by Japanese researchers (62 written in Japanese and 3 written in English), which employed 171 clones and 32 offspring, and categorizes them according to the following 7 categories: (1) genetic similarities and muzzle prints, (2) hematology and clinical chemistry findings, (3) pathology, (4) growth performance, (5) reproductive performance, (6) meat production performance and (7) milk production performance. No remarkable differences in health status or reproductive performance were found among conventionally bred cattle, somatic cell cloned cattle surviving to adulthood and offspring of somatic cell cloned cattle. Similarities in growth performance and meat quality were observed between nuclear donor cattle and their clones. The growth curves of the offspring resembled those of their full siblings.

  15. Characterization of T cell clones from chagasic patients: predominance of CD8 surface phenotype in clones from patients with pathology

    Directory of Open Access Journals (Sweden)

    Washington R. Cuna

    1995-08-01

    Full Text Available Human Chagas' disease, caused by the protozoan Trypanosoma cruzi, is associated with pathological processes whose mechanisms are not known. To address this question, T cell lines were developed from chronic chagasic patients peripheral blood mononuclear cells (PBMC and cloned. These T cell clones (TCC were analyzed phenotypically with monoclonal antibodies by the use of a fluorescence microscope. The surface phenotype of the TCC from the asymptomatic patient were predominantly CD4 positive (86%. On the contrary, the surface phenotype CD8 was predominant in the TCC from the patients suffering from cardiomegaly with right bundle branch block (83%, bradycardia with megacolon (75 % and bradycardia (75%. Future studies will be developed in order to identify the antigens eliciting these T cell subpopulations.

  16. Control of the proportion of inner cells by asymmetric divisions and the ensuing resilience of cloned rabbit embryos

    Science.gov (United States)

    Duranthon, Véronique

    2018-01-01

    ABSTRACT Mammalian embryo cloning by nuclear transfer has a low success rate. This is hypothesized to correlate with a high variability of early developmental steps that segregate outer cells, which are fated to extra-embryonic tissues, from inner cells, which give rise to the embryo proper. Exploring the cell lineage of wild-type embryos and clones, imaged in toto until hatching, highlights the respective contributions of cell proliferation, death and asymmetric divisions to phenotypic variability. Preferential cell death of inner cells in clones, probably pertaining to the epigenetic plasticity of the transferred nucleus, is identified as a major difference with effects on the proportion of inner cell. In wild type and clones, similar patterns of outer cell asymmetric divisions are shown to be essential to the robust proportion of inner cells observed in wild type. Asymmetric inner cell division, which is not described in mice, is identified as a regulator of the proportion of inner cells and likely gives rise to resilient clones. PMID:29567671

  17. Recovery of infectious pariacoto virus from cDNA clones and identification of susceptible cell lines.

    Science.gov (United States)

    Johnson, K N; Ball, L A

    2001-12-01

    Pariacoto virus (PaV) is a nodavirus that was recently isolated in Peru from the Southern armyworm, Spodoptera eridania. Virus particles are non enveloped and about 30 nm in diameter and have T=3 icosahedral symmetry. The 3.0-A crystal structure shows that about 35% of the genomic RNA is icosahedrally ordered, with the RNA forming a dodecahedral cage of 25-nucleotide (nt) duplexes that underlie the inner surface of the capsid. The PaV genome comprises two single-stranded, positive-sense RNAs: RNA1 (3,011 nt), which encodes the 108-kDa catalytic subunit of the RNA-dependent RNA polymerase, and RNA2 (1,311 nt), which encodes the 43-kDa capsid protein precursor alpha. In order to apply molecular genetics to the structure and assembly of PaV, we identified susceptible cell lines and developed a reverse genetic system for this virus. Cell lines that were susceptible to infection by PaV included those from Spodoptera exigua, Helicoverpa zea and Aedes albopictus, whereas cells from Drosophila melanogaster and Spodoptera frugiperda were refractory to infection. To recover virus from molecular clones, full-length cDNAs of PaV RNAs 1 and 2 were cotranscribed by T7 RNA polymerase in baby hamster kidney cells that expressed T7 RNA polymerase. Lysates of these cells were infectious both for cultured cells from Helicoverpa zea (corn earworm) and for larvae of Galleria mellonella (greater wax moth). The combination of infectious cDNA clones, cell culture infectivity, and the ability to produce milligram amounts of virus allows the application of DNA-based genetic methods to the study of PaV structure and assembly.

  18. A Seminar on Human Cloning: Cloning in Reproductive Medicine

    OpenAIRE

    Illmensee, Karl

    2001-01-01

    This review article summarizes the historical development of mammalian cloning, presents current advances and presumed risk factors in the field of reproductive cloning, discusses possible clinical applications of therapeutic and diagnostic cloning and outlines prospective commercial trends in pharmacytical cloning. Predictable progress in biotechnology and stem cell engineering should prove to be advantageous for patients' health and for novel benefits in reproductive and regenerative medicine.

  19. T Cell Receptor Vβ Staining Identifies the Malignant Clone in Adult T cell Leukemia and Reveals Killing of Leukemia Cells by Autologous CD8+ T cells.

    Directory of Open Access Journals (Sweden)

    Aileen G Rowan

    2016-11-01

    Full Text Available There is growing evidence that CD8+ cytotoxic T lymphocyte (CTL responses can contribute to long-term remission of many malignancies. The etiological agent of adult T-cell leukemia/lymphoma (ATL, human T lymphotropic virus type-1 (HTLV-1, contains highly immunogenic CTL epitopes, but ATL patients typically have low frequencies of cytokine-producing HTLV-1-specific CD8+ cells in the circulation. It remains unclear whether patients with ATL possess CTLs that can kill the malignant HTLV-1 infected clone. Here we used flow cytometric staining of TCRVβ and cell adhesion molecule-1 (CADM1 to identify monoclonal populations of HTLV-1-infected T cells in the peripheral blood of patients with ATL. Thus, we quantified the rate of CD8+-mediated killing of the putative malignant clone in ex vivo blood samples. We observed that CD8+ cells from ATL patients were unable to lyse autologous ATL clones when tested directly ex vivo. However, short in vitro culture restored the ability of CD8+ cells to kill ex vivo ATL clones in some donors. The capacity of CD8+ cells to lyse HTLV-1 infected cells which expressed the viral sense strand gene products was significantly enhanced after in vitro culture, and donors with an ATL clone that expressed the HTLV-1 Tax gene were most likely to make a detectable lytic CD8+ response to the ATL cells. We conclude that some patients with ATL possess functional tumour-specific CTLs which could be exploited to contribute to control of the disease.

  20. Protein-free transfection of CHO host cells with an IgG-fusion protein: selection and characterization of stable high producers and comparison to conventionally transfected clones.

    Science.gov (United States)

    Lattenmayer, Christine; Loeschel, Martina; Schriebl, Kornelia; Steinfellner, Willibald; Sterovsky, Thomas; Trummer, Evelyn; Vorauer-Uhl, Karola; Müller, Dethardt; Katinger, Hermann; Kunert, Renate

    2007-04-15

    In order to improve the current techniques of cell cultivation in the absence of serum, we have developed a protein-free transfection protocol for CHO cells, based on the Nucleofector technology. After starting with a heterogeneous pool of primary transfectants which express the fusion protein EpoFc, we isolated single clones and compared them with parallel clones generated by lipofection in serum-dependent cultivation. Our intensive characterization program was based on determination of specific productivity (q(p)) and analysis of genetic parameters. In two nucleofection experiments, transfection with 5 microg of DNA resulted in best productivities of the primary cell pools. After subcloning, the q(p) could be raised up to 27 pg x cells(-1) x day(-1). While the serum-dependent transfectants exhibited specific productivities up to 57 pg x cells(-1) x day(-1) in serum-dependent cultivation, a significant decrease that resulted in the range of q(p) of the protein-free transfectants was observed after switching to protein-free conditions. Investigation of genetic parameters revealed higher mRNA levels and gene copy numbers (GCN) for the protein-free adapted serum-dependent transfectants. Therefore, we assume that problems during protein-free adaptation (PFA) lead to a less efficient translation machinery after serum deprivation. We describe the generation of stable-producing recombinant CHO clones by protein-free transfection of a protein-free adapted host cell line, which reduces the risk of adverse clonal changes after PFA. The main advantage of this approach is the earlier predictability of clone behavior, which makes the generation of production clones by protein-free transfection, a viable and highly efficient strategy for recombinant cell line development. (c) 2006 Wiley Periodicals, Inc.

  1. Human somatic cell nuclear transfer and cloning.

    Science.gov (United States)

    2012-10-01

    This document presents arguments that conclude that it is unethical to use somatic cell nuclear transfer (SCNT) for infertility treatment due to concerns about safety; the unknown impact of SCNT on children, families, and society; and the availability of other ethically acceptable means of assisted reproduction. This document replaces the ASRM Ethics Committee report titled, "Human somatic cell nuclear transfer (cloning)," last published in Fertil Steril 2000;74:873-6. Copyright © 2012 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  2. Molecular characterization of a Leishmania donovani cDNA clone with similarity to human 20S proteasome a-type subunit

    DEFF Research Database (Denmark)

    Christensen, C B; Jørgensen, L; Jensen, A T

    2000-01-01

    Using plasma from patients infected or previously infected with Leishmania donovanii, we isolated a L. donovanii cDNA clone with similarity to the proteasome a-type subunit from humans and other eukaryotes. The cDNA clone, designated LePa, was DNA sequenced and Northern blot analysis of L....... donovanii poly(A(+))mRNA indicated the isolation of a full length cDNA clone with a transcript size of 1.9 kb. The expressed recombinant LePa fusion protein induced proliferation of peripheral blood mononuclear cells in one out of seven patients who had suffered from visceral leishmaniasis. Plasma from 16...

  3. Somatic cell cloning in Buffalo (Bubalus bubalis): effects of interspecies cytoplasmic recipients and activation procedures.

    Science.gov (United States)

    Kitiyanant, Y; Saikhun, J; Chaisalee, B; White, K L; Pavasuthipaisit, K

    2001-01-01

    Successful nuclear transfer (NT) of somatic cell nuclei from various mammalian species to enucleated bovine oocytes provides a universal cytoplast for NT in endangered or extinct species. Buffalo fetal fibroblasts were isolated from a day 40 fetus and were synchronized in presumptive G(0) by serum deprivation. Buffalo and bovine oocytes from abattoir ovaries were matured in vitro and enucleated at 22 h. In the first experiment, we compared the ability of buffalo and bovine oocyte cytoplasm to support in vitro development of NT embryos produced by buffalo fetal fibroblasts as donor nuclei. There were no significant differences (p > 0.05) between the NT embryos derived from buffalo and bovine oocytes, in fusion (74% versus 71%) and cleavage (77% versus 75%) rates, respectively. No significant differences were also observed in blastocyst development (39% versus 33%) and the mean cell numbers of day 7 cloned blastocysts (88.5 +/- 25.7 versus 51.7 +/- 5.4). In the second experiment, we evaluated the effects of activation with calcium ionophore A23187 on development of NT embryos after electrical fusion. A significantly higher (p cloned buffalo blastocysts similar to those transferred into buffalo oocytes. Calcium ionophore used in conjunction with 6-DMAP effectively induces NT embryo development.

  4. Functional heterogeneity and heritability in CHO cell populations.

    Science.gov (United States)

    Davies, Sarah L; Lovelady, Clare S; Grainger, Rhian K; Racher, Andrew J; Young, Robert J; James, David C

    2013-01-01

    In this study, we address the hypothesis that it is possible to exploit genetic/functional variation in parental Chinese hamster ovary (CHO) cell populations to isolate clonal derivatives that exhibit superior, heritable attributes for biomanufacturing--new parental cell lines which are inherently more "fit for purpose." One-hundred and ninety-nine CHOK1SV clones were isolated from a donor CHOK1SV parental population by limiting dilution cloning and microplate image analysis, followed by primary analysis of variation in cell-specific proliferation rate during extended deep-well microplate suspension culture of individual clones to accelerate genetic drift in isolated cultures. A subset of 100 clones were comparatively evaluated for transient production of a recombinant monoclonal antibody (Mab) and green fluorescent protein following transfection of a plasmid vector encoding both genes. The heritability of both cell-specific proliferation rate and Mab production was further assessed using a subset of 23 clones varying in functional capability that were subjected to cell culture regimes involving both cryopreservation and extended sub-culture. These data showed that whilst differences in transient Mab production capability were not heritable per se, clones exhibiting heritable variation in specific proliferation rate, endocytotic transfectability and N-glycan processing were identified. Finally, for clonal populations most "evolved" by extended sub-culture in vitro we investigated the relationship between cellular protein biomass content, specific proliferation rate and cell surface N-glycosylation. Rapid-specific proliferation rate was inversely correlated to CHO cell size and protein content, and positively correlated to cell surface glycan content, although substantial clone-specific variation in ability to accumulate cell biomass was evident. Taken together, our data reveal the dynamic nature of the CHO cell functional genome and the potential to evolve and

  5. Molecular Characterization of Methicillin Resistant Staphylococcus aureus Strains Isolated from Intensive Care Units in Iran: ST22-SCCmec IV/t790 Emerges as the Major Clone.

    Science.gov (United States)

    Goudarzi, Mehdi; Goudarzi, Hossein; Sá Figueiredo, Agnes Marie; Udo, Edet E; Fazeli, Maryam; Asadzadeh, Mohammad; Seyedjavadi, Sima Sadat

    2016-01-01

    The emergence of methicillin-resistant Staphylococcus aureus (MRSA) in different patient populations is a major public health concern. This study determined the prevalence and distribution of circulating molecular types of MRSA in hospitalized patients in ICU of hospitals in Tehran. A total of 70 MRSA isolates were collected from patients in eight hospitals. Antimicrobial resistance patterns were determined using the disk diffusion method. The presence of toxin encoding genes and the vancomycin resistance gene were determined by PCR. The MRSA isolates were further analyzed using multi-locus sequence, spa, SCCmec, and agr typing. The MRSA prevalence was 93.3%. Antimicrobial susceptibility testing revealed a high resistance rate (97.1%) to ampicillin and penicillin. The rate of resistance to the majority of antibiotics tested was 30% to 71.4%. Two isolates belonging to the ST22-SCCmec IV/t790 clone (MIC ≥ 8 μg/ml) had intermediate resistance to vancomycin. The majority of MRSA isolates (24.3%) were associated with the ST22-SCCmec IV/t790 clone; the other MRSA clones were ST859-SCCmec IV/t969 (18.6%), ST239-SCCmec III/t037 (17.1%), and ST291-SCCmec IV/t030 (8.6%). The circulating MRSA strains in Iranian hospitals were genetically diverse with a relatively high prevalence of the ST22-SCCmec IV/t790 clone. These findings support the need for future surveillance studies on MRSA to better elucidate the distribution of existing MRSA clones and detect emergence of new MRSA clones.

  6. Generation of a panel of somatic cell hybrids containing unselected fragments of human chromosome 10 by X-ray irradiation and cell fusion: Application to isolating the MEN2A region in hybrid cells

    International Nuclear Information System (INIS)

    Goodfellow, P.J.; Povey, S.; Nevanlinna, H.A.; Goodfellow, P.N.

    1990-01-01

    We have used X-ray irradiation and cell fusion to generate somatic cell hybrids containing fragments of human chromosome 10. Our experiments were directed towards isolating the region of the MEN2A gene in hybrids and to use those as the source of DNA for cloning and mapping new markers from near the MEN2A locus. A number of hybrid clones containing human sequences that are tightly linked to the MEN2A gene were identified. Some 25% of our hybrids, however, proved to contain more than one human chromosome 10-derived fragment or showed evidence of deletions and/or rearrangements. A detailed analysis of the human content of X-ray irradiation hybrids is required to assess the integrity and number of human fragments retained. Despite retention of multiple human-derived fragments, these hybrids will prove useful as cloning and mapping resources

  7. Identification of candidate vaccine antigens of bovine hemoparasites Theileria parva and Babesia bovis by use of helper T cell clones.

    Science.gov (United States)

    Brown, W C; Zhao, S; Logan, K S; Grab, D J; Rice-Ficht, A C

    1995-03-01

    Current vaccines for bovine hemoparasites utilize live attenuated organisms or virulent organisms administered concurrently with antiparasitic drugs. Although such vaccines can be effective, for most hemoparasites the mechanisms of acquired resistance to challenge infection with heterologous parasite isolates have not been clearly defined. Selection of potentially protective antigens has traditionally made use of antibodies to identify immunodominant proteins. However, numerous studies have indicated that induction of high antibody titers neither predicts the ability of an antigen to confer protective immunity nor correlates with protection. Because successful parasites have evolved antibody evasion tactics, alternative strategies to identify protective immunogens should be used. Through the elaboration of cytokines, T helper 1-(Th1)-like T cells and macrophages mediate protective immunity against many intracellular parasites, and therefore most likely play an important role in protective immunity against bovine hemoparasites. CD4+ T cell clones specific for soluble or membrane antigens of either Theileria parva schizonts or Babesia bovis merozoites were therefore employed to identify parasite antigens that elicit strong Th cell responses in vitro. Soluble cytosolic parasite antigen was fractionated by gel filtration, anion exchange chromatography or hydroxylapatite chromatography, or a combination thereof, and fractions were tested for the ability to induce proliferation of Th cell clones. This procedure enabled the identification of stimulatory fractions containing T. parva proteins of approximately 10 and 24 kDa. Antisera raised against the purified 24 kDa band reacted with a native schizont protein of approximately 30 kDa. Babesia bovis-specific Th cell clones tested against fractionated soluble Babesia bovis merozoite antigen revealed the presence of at least five distinct antigenic epitopes. Proteins separated by gel filtration revealed four patterns of

  8. Molecular transformation, gene cloning, and gene expression systems for filamentous fungi

    Science.gov (United States)

    Gold, Scott E.; Duick, John W.; Redman, Regina S.; Rodriguez, Rusty J.

    2001-01-01

    This chapter discusses the molecular transformation, gene cloning, and gene expression systems for filamentous fungi. Molecular transformation involves the movement of discrete amounts of DNA into cells, the expression of genes on the transported DNA, and the sustainable replication of the transforming DNA. The ability to transform fungi is dependent on the stable replication and expression of genes located on the transforming DNA. Three phenomena observed in bacteria, that is, competence, plasmids, and restriction enzymes to facilitate cloning, were responsible for the development of molecular transformation in fungi. Initial transformation success with filamentous fungi, involving the complementation of auxotrophic mutants by exposure to sheared genomic DNA or RNA from wt isolates, occurred with low transformation efficiencies. In addition, it was difficult to retrieve complementing DNA fragments and isolate genes of interest. This prompted the development of transformation vectors and methods to increase efficiencies. The physiological studies performed with fungi indicated that the cell wall could be removed to generate protoplasts. It was evident that protoplasts could be transformed with significantly greater efficiencies than walled cells.

  9. Primer sets for cloning the human repertoire of T cell Receptor Variable regions

    Directory of Open Access Journals (Sweden)

    Santoro Claudio

    2008-08-01

    Full Text Available Abstract Background Amplification and cloning of naïve T cell Receptor (TR repertoires or antigen-specific TR is crucial to shape immune response and to develop immuno-based therapies. TR variable (V regions are encoded by several genes that recombine during T cell development. The cloning of expressed genes as large diverse libraries from natural sources relies upon the availability of primers able to amplify as many V genes as possible. Results Here, we present a list of primers computationally designed on all functional TR V and J genes listed in the IMGT®, the ImMunoGeneTics information system®. The list consists of unambiguous or degenerate primers suitable to theoretically amplify and clone the entire TR repertoire. We show that it is possible to selectively amplify and clone expressed TR V genes in one single RT-PCR step and from as little as 1000 cells. Conclusion This new primer set will facilitate the creation of more diverse TR libraries than has been possible using currently available primer sets.

  10. Isolation of parafluorophenylalanine-resistant mutants from HeLa cell cultures

    International Nuclear Information System (INIS)

    Yim, L.K.; Stuart, W.D.

    1983-01-01

    This report describes a method to isolate temperature-conditional phenylalanine transport mutants from the transformed human cell line HeLa. Using ultraviolet light as a mutagenic agent and DL-parafluorophenylalanine (PFPA), a poisonous analogue of L-phenylalanine, as a selective agent, mutagenized cells were selected for survival in the presence of PFPA at a temperature of 39 degrees C. Survivors of the mutagenesis and selection procedures were removed from the culture dishes by trypsin and cloned at a temperature of 35 degrees C. Seven of these lines isolated demonstrated continued resistance to PFPA at 39 degrees C. These lines were tested for uptake of L-phenylalanine at an external concentration of 100 microM and for continued resistance to PFPA at two concentrations. Cells were tested at 35 and at 39 degrees C. The data were compared to those obtained for the parental HeLa cell line under identical conditions. The seven mutant cell lines demonstrated varying resistances to PFPA and varying levels of accumulation of L-phenylalanine when tested at 35 and 39 degrees C. Three mutant lines were additionally tested for L-phenylalanine tRNA charging levels and for transport of L-arginine. The lines had parental cell levels of tRNA charging and L-arginine transport which suggest that the induced genetic defect affects a specific L-phenylalanine transport system

  11. Combining EL4-B5-based B-cell stimulation and phage display technology for the successful isolation of human anti-Scl-70 autoantibody fragments.

    Science.gov (United States)

    Weber, Malte; Weiss, Etienne; Engel, Alfred M

    2003-07-01

    Scl-70 is the major antigen recognised by autoantibodies in the sera of patients with systemic sclerosis (SSc). The autoantibodies that specifically react with Scl-70 are highly characteristic of the disease and represent valuable markers for the diagnosis of SSc. We describe a novel strategy for cloning autoantibody fragments starting with a small blood sample from an SSc patient. B cells isolated from the collected peripheral blood mononuclear cells (PBMCs) were cultured in vitro using the EL4-B5 system. Anti-Scl-70 IgG-producing cells were pooled for RNA preparation followed by the generation of phagemid libraries of approximately 10(7) independent single-chain Fvs (scFvs). The screening of these libraries by phage display allowed us to isolate four anti-Scl-70 scFvs following three rounds of biopanning. About 10 times more starting blood material was needed to generate scFv libraries of similar size from PBMCs of an SSc patient and only two anti-Scl-70 scFvs were isolated after three rounds of phage selection. Together, this work shows that functional autoantibody fragments can be advantageously cloned after in vitro expansion of B cells. The isolated anti-Scl-70 autoantibody fragments represent useful tools for calibrating SSc diagnostic assays.

  12. Persistence and selection of an expanded B-cell clone in the setting of rituximab therapy for Sjögren's syndrome.

    Science.gov (United States)

    Hershberg, Uri; Meng, Wenzhao; Zhang, Bochao; Haff, Nancy; St Clair, E William; Cohen, Philip L; McNair, Patrice D; Li, Ling; Levesque, Marc C; Luning Prak, Eline T

    2014-02-11

    Subjects with primary Sjögren's syndrome (SjS) have an increased risk of developing B-cell lymphoma and may harbor monoclonal B-cell expansions in the peripheral blood. Expanded B-cell clones could be pathogenic, and their persistence could exacerbate disease or predispose toward the development of lymphoma. Therapy with anti-CD20 (rituximab) has the potential to eliminate expanded B-cell clones and thereby potentially ameliorate disease. This study was undertaken to identify and track expanded B-cell clones in the blood of subjects with primary SjS who were treated with rituximab. To determine whether circulating B-cell clones in subjects with primary SjS emerge or remain after B cell-depleting therapy with rituximab, we studied the antibody heavy-chain repertoire. We performed single-memory B-cell and plasmablast sorting and antibody heavy-chain sequencing in six rituximab-treated SjS subjects over the course of a 1-year follow-up period. Expanded B-cell clones were identified in four out of the six rituximab-treated SjS subjects, based upon the independent amplification of sequences with identical or highly similar VH, DH, and JH gene segments. We identified one SjS subject with a large expanded B-cell clone that was present prior to therapy and persisted after therapy. Somatic mutations in the clone were numerous but did not increase in frequency over the course of the 1-year follow-up, suggesting that the clone had been present for a long period of time. Intriguingly, a majority of the somatic mutations in the clone were silent, suggesting that the clone was under chronic negative selection. For some subjects with primary SjS, these data show that (a) expanded B-cell clones are readily identified in the peripheral blood, (b) some clones are not eliminated by rituximab, and (c) persistent clones may be under chronic negative selection or may not be antigen-driven. The analysis of sequence variation among members of an expanded clone may provide a novel means

  13. Do endothelial cells belong to the primitive stem leukemic clone in CML? Role of extracellular vesicles.

    Science.gov (United States)

    Ramos, Teresa L; Sánchez-Abarca, Luis Ignacio; López-Ruano, Guillermo; Muntión, Sandra; Preciado, Silvia; Hernández-Ruano, Montserrat; Rosado, Belén; de las Heras, Natalia; Chillón, M Carmen; Hernández-Hernández, Ángel; González, Marcos; Sánchez-Guijo, Fermín; Del Cañizo, Consuelo

    2015-08-01

    The expression of BCR-ABL in hematopoietic stem cells is a well-defined primary event in chronic myeloid leukemia (CML). Some reports have described the presence of BCR-ABL on endothelial cells from CML patients, suggesting the origin of the disease in a primitive hemangioblastic cell. On the other hand, extracellular vesicles (EVs) released by CML leukemic cells are involved in the angiogenesis modulation process. In the current work we hypothesized that EVs released from BCR-ABL(+) cells may carry inside the oncogene that can be transferred to endothelial cells leading to the expression of both BCR-ABL transcript and the oncoprotein. EVs from K562 cells and plasma of newly diagnosed CML patients were isolated by ultracentrifugation. RT-PCR analysis detected the presence of BCR-ABL RNA in the EVs isolated from both K562 cells and plasma of CML patients. The incorporation of these EVs into endothelial cells was demonstrated by flow cytometry and fluorescence microscopy showed that after 24h of incubation most EVs were incorporated. BCR-ABL transcripts were detected in all experiments on endothelial cells incubated with EVs from both sources. The presence of BCR-ABL on endothelial cells incubated with Philadelphia(+) EVs was also confirmed by Western blot assays. In summary, endothelial cells acquire BCR-ABL RNA and the oncoprotein after incubation with EVs released from Ph(+) positive cells (either from K562 cells or from plasma of newly diagnosed CML patients). This results challenge the hypothesis that endothelial cells may be part of the Philadelphia(+) clone in CML. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Differentiation of human B lymphocyte subpopulations induced by an alloreactive helper T-cell clone

    International Nuclear Information System (INIS)

    Anderson, S.J.; Hummell, D.S.; Lawton, A.R.

    1988-01-01

    We have used cloned alloreactive helper T cells to determine if direct T cell-B cell interaction can induce differentiation of human peripheral blood B cells which do not respond to pokeweed mitogen (PWM). T-cell clone 2F8 was derived from a one-way mixed lymphocyte reaction. 2F8 cells are T3+T4+T8-IL-2R+ and proliferate in response to irradiated stimulator cells, but not autologous cells, in the absence of exogenous interleukin-2. 2F8 cells provide allospecific help for polyclonal proliferation and differentiation of B cells in the absence of any other stimulus. The magnitude of this response is comparable to that of the response of the same B cells to PWM and fresh autologous T cells. 2F8 cells could also provide nonspecific help for unrelated donor B cells in the presence of PWM, with no requirement for costimulation by irradiated stimulator cells. Allospecific stimulation of B cells was completely inhibited by antibodies to class II major histocompatibility complex (MHC) framework determinants and was abrogated by 1000-rad irradiation. Cloned 2F8 T cells stimulated differentiation of both small, high-density B cells and larger B cells, generating up to 30% plasma cells with either fraction. B cells forming rosettes with mouse erythrocytes were also induced to differentiate by the helper T cell clone. As found previously, neither small, high-density B cells nor mouse rosette+ B cells responded well to PWM. Direct interaction with allospecific T cells induces differentiation of a broader spectrum of B cells than soluble growth and differentiation factors in conjunction with polyclonal activators such as PWM and protein A containing staphylococci

  15. Dominance of multidrug-resistant Denmark(14)-32 (ST230) clone among Streptococcus pneumoniae serotype 19A isolates causing pneumococcal disease in Bulgaria from 1992 to 2013.

    Science.gov (United States)

    Setchanova, Lena Petrova; Alexandrova, Alexandra; Dacheva, Daniela; Mitov, Ivan; Kaneva, Radka; Mitev, Vanio

    2015-02-01

    A pneumococcal conjugate vaccine (PCV10) was introduced in Bulgarian national immunization program since April 2010. Clonal composition based on pulsed-field gel electrophoresis and multilocus sequence typing genotyping of 52 serotype 19A Streptococcus pneumoniae isolates was analyzed. These were invasive and respiratory isolates collected between 1992 and 2013 from both children (78.8% clone. The most frequent sequence type (ST) was ST230 (48.1%) and together with four other closely related STs (15.4%), belonging to ST1611, ST276, ST7466, and ST2013, which were single- and double-locus variants; they were included in the main CC230. The disappearance of highly drug-resistant ST663 clone and emergence of new clones as CC320 and CC199 was also observed among the rest 19A isolates. A comparison of clonal composition between invasive and noninvasive isolates did not show a great genetic diversity among both kinds of isolates. Continuous surveillance of serotype 19A population following the introduction of PCV10 is essential to evaluate the impact of the vaccine on the epidemiology of this serotype.

  16. Cloning of cDNA encoding steroid 11β-hydroxylase (P450c11)

    International Nuclear Information System (INIS)

    Chua, S.C.; Szabo, P.; Vitek, A.; Grzeschik, K.H.; John, M.; White, P.C.

    1987-01-01

    The authors have isolated bovine and human adrenal cDNA clones encoding the adrenal cytochrome P-450 specific for 11β-hydroxylation (P450c11). A bovine adrenal cDNA library constructed in the bacteriophage λ vector gt10 was probed with a previously isolated cDNA clone corresponding to part of the 3' untranslated region of the 4.2-kilobase (kb) mRNA encoding P450c11. Several clones with 3.2-kb cDNA inserts were isolated. Sequence analysis showed that they overlapped the original probe by 300 base pairs (bp). Combined cDNA and RNA sequence data demonstrated a continuous open reading frame of 1509 bases. P450c11 is predicted to contain 479 amino acid residues in the mature protein in addition to a 24-residue amino-terminal mitochondrial signal sequence. A bovine clone was used to isolate a homologous clone with a 3.5-kb insert from a human adrenal cDNA library. A region of 1100 bp was 81% homologous to 769 bp of the coding sequence of the bovine cDNA except for a 400-bp segment presumed to be an unprocessed intron. Hybridization of the human cDNA to DNA from a panel of human-rodent somatic cell hybrid lines and in situ hybridization to metaphase spreads of human chromosomes localized the gene to the middle of the long arm of chromosome 8. These data should be useful in developing reagents for heterozygote detection and prenatal diagnosis of 11β-hydroxylase deficiency, the second most frequent cause of congenital adrenal hyperplasia

  17. Exact, time-independent estimation of clone size distributions in normal and mutated cells.

    Science.gov (United States)

    Roshan, A; Jones, P H; Greenman, C D

    2014-10-06

    Biological tools such as genetic lineage tracing, three-dimensional confocal microscopy and next-generation DNA sequencing are providing new ways to quantify the distribution of clones of normal and mutated cells. Understanding population-wide clone size distributions in vivo is complicated by multiple cell types within observed tissues, and overlapping birth and death processes. This has led to the increased need for mathematically informed models to understand their biological significance. Standard approaches usually require knowledge of clonal age. We show that modelling on clone size independent of time is an alternative method that offers certain analytical advantages; it can help parametrize these models, and obtain distributions for counts of mutated or proliferating cells, for example. When applied to a general birth-death process common in epithelial progenitors, this takes the form of a gambler's ruin problem, the solution of which relates to counting Motzkin lattice paths. Applying this approach to mutational processes, alternative, exact, formulations of classic Luria-Delbrück-type problems emerge. This approach can be extended beyond neutral models of mutant clonal evolution. Applications of these approaches are twofold. First, we resolve the probability of progenitor cells generating proliferating or differentiating progeny in clonal lineage tracing experiments in vivo or cell culture assays where clone age is not known. Second, we model mutation frequency distributions that deep sequencing of subclonal samples produce.

  18. In vitro and in vivo genotoxic effects of somatic cell nuclear transfer cloned cattle meat.

    Science.gov (United States)

    Lee, Nam-Jin; Yang, Byoung-Chul; Jung, Yu-Ri; Lee, Jung-Won; Im, Gi-Sun; Seong, Hwan-Hoo; Park, Jin-Ki; Kang, Jong-Koo; Hwang, Seongsoo

    2011-09-01

    Although the nutritional composition and health status after consumption of the meat and milk derived from both conventionally bred (normal) and somatic cell nuclear transferred (cloned) animals and their progeny are not different, little is known about their food safeties like genetic toxicity. This study is performed to examine both in vitro (bacterial mutation and chromosome aberration) and in vivo (micronucleus) genotoxicity studies of cloned cattle meat. The concentrations of both normal and cloned cattle meat extracts (0-10×) were tested to five strains of bacteria (Salmonella typhimurium: TA98, TA100, TA1535, and TA1537; Escherichia coli: WP2uvrA) for bacterial mutation and to Chinese hamster lung (CHL/IU) cells for chromosome aberration, respectively. For micronucleus test, ICR mice were divided into five dietary groups: commercial pellets (control), pellets containing 5% (N-5) and 10% (N-10) normal cattle meat, and pellets containing 5% (C-5) and 10% (C-10) cloned cattle meat. No test substance-related genotoxicity was noted in the five bacterial strains, CHL/IU cells, or mouse bone marrow cells, suggesting that the cloned cattle meat potentially may be safe in terms of mutagenic hazards. Thus, it can be postulated that the cloned cattle meat do not induce any harmful genotoxic effects in vitro and in vivo. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. Variation in biological properties of cauliflower mosaic virus clones.

    Science.gov (United States)

    al-Kaff, N; Covey, S N

    1994-11-01

    Infectious clones were prepared from virion DNA of three cauliflower mosaic virus (CaMV) isolates, 11/3, Xinjiang (XJ), and Aust, to investigate pathogenic variation in virus populations. Of 10 infectious clones obtained for isolate 11/3, four pathotypes were identified, each producing symptoms in turnip that differed from those of the 11/3 wild-type. Virus from two clonal groups of 11/3 was transmissible by aphids whereas that from two others was not. Of the five infectious clones obtained from isolate XJ, two groups were identified, one of which differed symptomatically from the wild-type. Only one infectious clone was obtained from isolate Aust and this had properties similar to the wild-type. Restriction enzyme polymorphisms were found in some clonal groups and these correlated with symptoms. Other groups with different pathogenic properties could not be distinguished apart by restriction site polymorphisms. Further variation was observed in the nucleotide sequences of gene II (coding for aphid transmission factor) from these viruses as compared with other CaMV isolates. In the aphid non-transmissible clones of isolate 11/3, one had a Gly to Arg mutation in gene II similar to that of other non-deleted non-transmissible CaMV isolates. The second had a 322 bp deletion at the site of a small direct repeat similar to that of isolate CM4-184 although occurring in a different position. The gene II deletion of isolate 11/3 produced a frame-shift that separated genes II and III by 60 bp. Most CaMV clones studied remained biologically stable producing similar symptoms during subsequent passages. However, one clone (11/3-7) produced two new biotypes during its first passage suggesting that it was relatively unstable. Our results show that wild-type populations of CaMV contain a range of infectious genome variants with contrasting biological properties and differing stability. We suggest that a variety of significant viral phenotypic changes can occur during each

  20. Culture supernatants from V. cholerae O1 El Tor strains isolated from different geographic areas induce cell vacuolation and cytotoxicity.

    Science.gov (United States)

    Vidal, Jorge E; Enríquez-Rincón, Fernando; Giono-Cerezo, Silvia; Ribas-Aparicio, Rosa María; Figueroa-Arredondo, Paula

    2009-01-01

    To investigate whether the HlyA-induced vacuolating effect is produced by V. cholerae O1 ElTor strains isolated from different geographic origins, including Mexico. Supernatant-induced haemolysis, vacuolating activity and cytotoxicity in Vero cells were recorded. PCR, RFLP analysis and molecular cloning were performed. All ElTor strains analyzed induced cellular vacuolation. Ribotype 2 strains isolates from the U.S. gulf coast yielded the highest titer of vacuolating activity. Eight of nine strains were haemolytic, while all strains were PCR positive for the hlyA gene. We cloned the hlyA gene from two ElTor strains, a toxigenic (2514-88, ctxAB+) and a non-toxigenic Mexican strain (CM 91-3, ctxAB-). Supernatant from those recombinant E. coli strains induced haemolysis, cell vacuolation and cytotoxicity. RFLP-PCR analysis revealed similarities in the hlyA gene from all strains tested. The HlyA-induced vacuolating effect is a widespread phenotype of epidemic V. cholerae O1 ElTor strains.

  1. The Three Major Spanish Clones of Penicillin-Resistant Streptococcus pneumoniae Are the Most Common Clones Recovered in Recent Cases of Meningitis in Spain

    Science.gov (United States)

    Enright, Mark C.; Fenoll, Asunción; Griffiths, David; Spratt, Brian G.

    1999-01-01

    One hundred six isolates of Streptococcus pneumoniae recovered in Spain from patients with meningitis in 1997 and 1998 were characterized by multilocus sequence typing. A heterogeneous collection of genotypes was associated with meningitis in Spain: 65 different sequence types were resolved and, even at a genetic distance of 0.43, there were 37 distinct lineages. Thirty-eight percent of the isolates, including all isolates of serotypes 6B, 9V, 14, and 23F, were resistant to penicillin, and 24% of the isolates were members of the three major Spanish penicillin-resistant or multidrug-resistant clones of serotypes 6B, 9V, and 23F or serotype variants of these clones. These three clones (MICs, 1 to 2 μg of penicillin/ml) were the most common clones associated with pneumococcal meningitis in Spain during 1997 and 1998. Only two of the other clones associated with meningitis were penicillin resistant (MICs, 0.12 to 0.5 μg/ml). One of the two most prevalent penicillin-susceptible clones causing meningitis (serotype 3) has not been detected outside of Spain, whereas the other (serotype 18C) has been recovered from patients with meningitis in the United Kingdom, The Netherlands, and Denmark. The prevalence of meningitis caused by isolates of the three major Spanish penicillin-resistant or multiply antibiotic-resistant clones, which are now globally distributed, is disturbing and clearly establishes their ability to cause life-threatening disease. PMID:10488179

  2. Direct cloning from enrichment cultures, a reliable strategy for isolation of complete operons and genes from microbial consortia.

    Science.gov (United States)

    Entcheva, P; Liebl, W; Johann, A; Hartsch, T; Streit, W R

    2001-01-01

    Enrichment cultures of microbial consortia enable the diverse metabolic and catabolic activities of these populations to be studied on a molecular level and to be explored as potential sources for biotechnology processes. We have used a combined approach of enrichment culture and direct cloning to construct cosmid libraries with large (>30-kb) inserts from microbial consortia. Enrichment cultures were inoculated with samples from five environments, and high amounts of avidin were added to the cultures to favor growth of biotin-producing microbes. DNA was extracted from three of these enrichment cultures and used to construct cosmid libraries; each library consisted of between 6,000 and 35,000 clones, with an average insert size of 30 to 40 kb. The inserts contained a diverse population of genomic DNA fragments isolated from the consortia organisms. These three libraries were used to complement the Escherichia coli biotin auxotrophic strain ATCC 33767 Delta(bio-uvrB). Initial screens resulted in the isolation of seven different complementing cosmid clones, carrying biotin biosynthesis operons. Biotin biosynthesis capabilities and growth under defined conditions of four of these clones were studied. Biotin measured in the different culture supernatants ranged from 42 to 3,800 pg/ml/optical density unit. Sequencing the identified biotin synthesis genes revealed high similarities to bio operons from gram-negative bacteria. In addition, random sequencing identified other interesting open reading frames, as well as two operons, the histidine utilization operon (hut), and the cluster of genes involved in biosynthesis of molybdopterin cofactors in bacteria (moaABCDE).

  3. Cloning and chromosomal assignment of a human cDNA encoding a T cell- and natural killer cell-specific trypsin-like serine protease

    International Nuclear Information System (INIS)

    Gershenfeld, H.K.; Hershberger, R.J.; Shows, T.B.; Weissman, I.L.

    1988-01-01

    A cDNA clone encoding a human T cell- and natural killer cell-specific serine protease was obtained by screening a phage λgt10 cDNA library from phytohemagglutinin-stimulated human peripheral blood lymphocytes with the mouse Hanukah factor cDNA clone. In an RNA blot-hybridization analysis, this human Hanukah factor cDNA hybridized with a 1.3-kilobase band in allogeneic-stimulated cytotoxic T cells and the Jurkat cell line, but this transcript was not detectable in normal muscle, liver, tonsil, or thymus. By dot-blot hybridization, this cDNA hybridized with RNA from three cytolytic T-cell clones and three noncytolytic T-cell clones grown in vitro as well as with purified CD16 + natural killer cells and CD3 + , CD16 - T-cell large granular lymphocytes from peripheral blood lymphocytes (CD = cluster designation). The nucleotide sequence of this cDNA clone encodes a predicted serine protease of 262 amino acids. The active enzyme is 71% and 77% similar to the mouse sequence at the amino acid and DNA level, respectively. The human and mouse sequences conserve the active site residues of serine proteases--the trypsin-specific Asp-189 and all 10 cysteine residues. The gene for the human Hanukah factor serine protease is located on human chromosome 5. The authors propose that this trypsin-like serine protease may function as a common component necessary for lysis of target cells by cytotoxic T lymphocytes and natural killer cells

  4. Characterization of three newly established rat sarcoma cell clones

    Czech Academy of Sciences Publication Activity Database

    Holubová, Monika; Leba, M.; Sedmíková, M.; Vannucci, Luca; Horák, Vratislav

    2012-01-01

    Roč. 48, č. 10 (2012), s. 610-618 ISSN 1071-2690 R&D Projects: GA MŠk 2B08063 Institutional support: RVO:67985904 Keywords : sarcoma * cell clones * lewis rat Subject RIV: FD - Oncology ; Hematology Impact factor: 1.289, year: 2012

  5. DNA repair characteristics of a hybrid cell clone between xeroderma pigmentosum and Potorous tridactilis

    International Nuclear Information System (INIS)

    Ida, Kenji

    1986-01-01

    A hybrid cell clone PX1 was isolated by fusing UV sensitive XP20S(SV)neo, an SV-40-transformed, neomycin-resistant xeroderma pigmentosum (XP) cell line, and Pt K2, a rat kangaroo (Potorous tridactilis) cell line. The UV-survival curve of PX1 cells fell midway between those of Pt K2 and XP20S(SV)neo cells, since mean lethal doses(D 0 ) were 2.5, 4.7 and 0.27 J/m 2 for PX1, Pt K2 and XP20S(SV)neo, respectively. Amounts of unscheduled DNA synthesis (UDS) after UV, relative to normal human cells, were 60.4 % for Pt K2, 37.7 % for PX1 and 0.1 % for XP20S(SV)neo. Such relative UDS capacities for excision repair of Pt K2, PX1 and XP20S(SV)neo were also consistent with the respective relative capacities of host cell reactivation (HCR) of UV-irradiated Herpes simplex virus. Apparently, there was no single Pt K2 chromosome in the PX1 cells. One possibility is that a gene which may account for the partial restoration of the UV resistance has been transferred from Pt K2 to PX1. (author)

  6. Persistence and selection of an expanded B-cell clone in the setting of rituximab therapy for Sjögren’s syndrome

    Science.gov (United States)

    2014-01-01

    Introduction Subjects with primary Sjögren’s syndrome (SjS) have an increased risk of developing B-cell lymphoma and may harbor monoclonal B-cell expansions in the peripheral blood. Expanded B-cell clones could be pathogenic, and their persistence could exacerbate disease or predispose toward the development of lymphoma. Therapy with anti-CD20 (rituximab) has the potential to eliminate expanded B-cell clones and thereby potentially ameliorate disease. This study was undertaken to identify and track expanded B-cell clones in the blood of subjects with primary SjS who were treated with rituximab. Methods To determine whether circulating B-cell clones in subjects with primary SjS emerge or remain after B cell-depleting therapy with rituximab, we studied the antibody heavy-chain repertoire. We performed single-memory B-cell and plasmablast sorting and antibody heavy-chain sequencing in six rituximab-treated SjS subjects over the course of a 1-year follow-up period. Results Expanded B-cell clones were identified in four out of the six rituximab-treated SjS subjects, based upon the independent amplification of sequences with identical or highly similar VH, DH, and JH gene segments. We identified one SjS subject with a large expanded B-cell clone that was present prior to therapy and persisted after therapy. Somatic mutations in the clone were numerous but did not increase in frequency over the course of the 1-year follow-up, suggesting that the clone had been present for a long period of time. Intriguingly, a majority of the somatic mutations in the clone were silent, suggesting that the clone was under chronic negative selection. Conclusions For some subjects with primary SjS, these data show that (a) expanded B-cell clones are readily identified in the peripheral blood, (b) some clones are not eliminated by rituximab, and (c) persistent clones may be under chronic negative selection or may not be antigen-driven. The analysis of sequence variation among members of an

  7. Public perceptions of farm animal cloning in Europe

    DEFF Research Database (Denmark)

    Lassen, Jesper

    This report presents a picture of European opinion on farm animal cloning. In the report, both agricultural and biomedical applications of farm animal cloning are considered. With the arrival of Dolly, animal cloning became an integral part of the biotech debate, but this debate did not isolate...... animal cloning as a single issue....

  8. Epidemic Dissemination of a Carbapenem-Resistant Acinetobacter baumannii Clone Carrying armA Two Years After Its First Isolation in an Italian Hospital.

    Science.gov (United States)

    Milan, Annalisa; Furlanis, Linda; Cian, Franca; Bressan, Raffaela; Luzzati, Roberto; Lagatolla, Cristina; Deiana, Maria Luisa; Knezevich, Anna; Tonin, Enrico; Dolzani, Lucilla

    2016-12-01

    This study describes the dissemination of a carbapenem-resistant Acinetobacter baumannii (CRAB) strain in a university hospital in Northeast Italy. Characterization of the outbreak strain was combined with a retrospective analysis of all CRAB isolates collected in the same hospital during the 5 years preceding the outbreak, with the aim of elucidating the origin of the epidemic spread. The outbreak strain was shown to belong to the International Clone II and carry the bla OXA-23 gene, flanked by two ISAba1 sequences in opposite orientation (Tn2006 arrangement). The epidemic clone harbored also the bla OXA-66 allele of the carbapenemase intrinsic to A. baumannii, the determinant of ArmA 16S rRNA methylase and a class 1 integron, with the aacA4, catB8, and aadA1 cassette array. Genotype analysis, performed by macrorestriction analysis and VRBA, revealed that isolates related to outbreak strain had been sporadically collected from inpatients in the 2 years preceding outbreak start. Carriage of bla OXA-66 , armA, and the integron further supported relatedness of these isolates to the outbreak clone. Outbreak initially involved three medical wards, typically hosting elderly patients with a history of prolonged hospitalization. The study highlights the need to adopt strict infection control measures also when CRAB isolation appears to be a sporadic event.

  9. Hand-made cloned goat (Capra hircus) embryos—a comparison of different donor cells and culture systems.

    Science.gov (United States)

    Akshey, Yogesh S; Malakar, Dhruba; De, Arun K; Jena, Manoj K; Garg, Shweta; Dutta, Rahul; Pawar, Sachin Kumar; Mukesh, Manisha

    2010-10-01

    Nuclear transfer is a very effective method for propagation of valuable, extinct, and endangered animals. Hand-made cloning (HMC) is an efficient alternative to the conventional micromanipulator-based technique in some domestic species. The present study was carried out for the selection of suitable somatic cells as a nuclear donor and development of an optimum culture system for in vitro culture of zona-free goat cloned embryos. Cleavage and blastocyst rates were observed 72.06 ± 2.94% and 0% for fresh cumulus cells, 81.95 ± 3.40% and 12.74 ± 2.12% for cultured cumulus cells, and 92.94 ± 0.91% and 23.78 ± 3.33% for fetal fibroblast cells, respectively. There was a significant (p cloned embryos and donor cells. In conclusion, the present study describes that the fetal fibroblast cell is a suitable candidate as nuclear donor, and the flat surface culture system is suitable for zona-free blastocyst development by the hand-made cloning technique in the goat.

  10. T cell clones which share T cell receptor epitopes differ in phenotype, function and specificity

    NARCIS (Netherlands)

    Yssel, H.; Blanchard, D.; Boylston, A.; de Vries, J. E.; Spits, H.

    1986-01-01

    Recently, we described a monoclonal antibody (3D6) that reacts with the T cell receptor (Ti) of the T leukemic cell line HPB-ALL and that cross-reacts with 2-10% of the T cells of normal healthy individuals. In this study we report the establishment of T cell clones that are 3D6+ but that differ in

  11. Culture of somatic cells isolated from frozen-thawed equine semen using fluorescence-assisted cell sorting.

    Science.gov (United States)

    Brom-de-Luna, Joao Gatto; Canesin, Heloísa Siqueira; Wright, Gus; Hinrichs, Katrin

    2018-03-01

    Nuclear transfer using somatic cells from frozen semen (FzSC) would allow cloning of animals for which no other genetic material is available. Horses are one of the few species for which cloning is commercially feasible; despite this, there is no information available on the culture of equine FzSC. After preliminary trials on equine FzSC, recovered by density-gradient centrifugation, resulted in no growth, we hypothesized that sperm in the culture system negatively affected cell proliferation. Therefore, we evaluated culture of FzSC isolated using fluorescence-assisted cell sorting. In Exp. 1, sperm were labeled using antibodies to a sperm-specific antigen, SP17, and unlabeled cells were collected. This resulted in high sperm contamination. In Exp. 2, FzSC were labeled using an anti-MHC class I antibody. This resulted in an essentially pure population of FzSC, 13-25% of which were nucleated. Culture yielded no proliferation in any of nine replicates. In Exp. 3, 5 × 10 3 viable fresh, cultured horse fibroblasts were added to the frozen-thawed, washed semen, then this suspension was labeled and sorted as for Exp. 2. The enriched population had a mean of five sperm per recovered somatic cell; culture yielded formation of monolayers. In conclusion, an essentially pure population of equine FzSC could be obtained using sorting for presence of MHC class I antigens. No equine FzSC grew in culture; however, the proliferation of fibroblasts subjected to the same processing demonstrated that the labeling and sorting methods, and the presence of few sperm in culture, were compatible with cell viability. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Therapeutic cloning: The ethical limits

    International Nuclear Information System (INIS)

    Whittaker, Peter A.

    2005-01-01

    A brief outline of stem cells, stem cell therapy and therapeutic cloning is given. The position of therapeutic cloning with regard to other embryonic manipulations - IVF-based reproduction, embryonic stem formation from IVF embryos and reproductive cloning - is indicated. The main ethically challenging stages in therapeutic cloning are considered to be the nuclear transfer process including the source of eggs for this and the destruction of an embryo to provide stem cells for therapeutic use. The extremely polarised nature of the debate regarding the status of an early human embryo is noted, and some potential alternative strategies for preparing immunocompatible pluripotent stem cells are indicated

  13. Evaluación microbiológica y epidemiológica de los clones de Acinetobacter baumannii resistentes a los carbapenemes aislados en la unidad de cuidados intensivos de un Hospital Universitario de la ciudad de Buenos Aires Microbiological and epidemiological evaluation of carbapenem-resistant Acinetobacter baumannii clones isolated at an intensive care unit of a University Hospital in Buenos Aires city

    Directory of Open Access Journals (Sweden)

    C. H. Rodriguez

    2009-09-01

    Full Text Available Entre junio y diciembre de 2004 se estudiaron 33 aislamientos de Acinetobacter baumannii resistentes a los carbapenemes, aislados de materiales clínicos de 29 pacientes internados en la unidad de cuidados intensivos del Hospital de Clínicas de la Universidad de Buenos Aires. La distribución clonal de esos aislamientos fue la siguiente: clon I (n = 14, clon IV (n = 7, clon III (n = 6, clon VI (n = 3, clon II (n = 2 y clon X (n = 1.Veintiún aislamientos se recuperaron de materiales del tracto respiratorio inferior, 11 de ellos pertenecieron al clon I. Casi todos los aislamientos pertenecientes al clon III (5/6 se recuperaron de materiales no respiratorios, y todos los del clon IV se recuperaron de pacientes que no recibieron imipenem. En los aislamientos pertenecientes a los clones I y III se observó una mayor adherencia a catéteres, principalmente en los asociados con bacteriemias. La mayoría de los aislamientos de los clones I y IV sobrevivieron en materiales inertes durante un período superior a los 5 días. La totalidad de los aislamientos del clon III fueron sensibles a colistina, gentamicina y levofloxacina, mientras que los del clon I y la mayoría de los del clon IV sólo fueron sensibles a colistina y tetraciclinas.From June to December 2004, thirty-three carbapenem-resistant Acinetobacter baumannii isolates recovered from twenty nine patients at the intensive care unit in Hospital de Clínicas, Universidad de Buenos Aires, were studied. The isolates were categorized by molecular methods as: clone I (n = 14, clon IV (n = 7, clone III (n = 6, clone VI (n = 3, clone II (n = 2 and clone X (n = 1. Twenty one isolates were recovered from lower respiratory tract samples, 11 of which belonged to clon I. Clone III isolates were mainly recovered from non-respiratory samples (5/6. Clone IV isolates were recovered from patients not receiving previous imipenem therapy. The majority of the isolates belonging to clones I and IV were able to

  14. Peripheral blood and intrathyroidal T cell clones from patients with thyroid autoimmune diseases.

    Science.gov (United States)

    Massart, C; Caroff, G; Maugendre, D; Genetet, N; Gibassier, J

    1999-01-01

    For a better understanding of the pathogenesis of thyroid autoimmune diseases, we have studied morphological and functional properties of T clones from peripheral blood lymphocytes (PBL) and from intrathyroidal lymphocytes (ITL) obtained from 3 patients with Graves' disease or 1 Hashimoto's thyroiditis. Investigations were carried out on clones cultured alone or cocultured with autologous thyrocytes. Clonage efficiency ranged from 30% to 33% for PBL and 10% to 36% for ITL. A predominance of CD4-positive clones was observed whatever the origin of the lymphocytes or the autoimmune pathology. Gamma interferon (IFN-gamma) was detected in the majority (17/19) of the clones tested. Intracytoplasmic interleukin (IL-4) was secreted in 7/19 clones and both cytokines were produced in 5/19 clones. In coculture a proliferative response and tumour necrosis factor (TNF-alpha) production were observed with 6 clones (4 from Graves thyrocytes and 2 from thyroiditis). No cytotoxic clone was derived from Graves or thyroiditis tissues. These data demonstrate that the large majority of T clones are principally CD4-T cells; all the clones secreted TNF-alpha and a large majority produced IFN-gamma. Only a few clones produced IL-4 alone or associated with IFN-gamma. Six T clones induced proliferative response and of TNF-alpha secretion in coculture. Further investigations must be performed on these antigen-reactive T clones to analyse their role in the pathogenesis of the human thyroid autoimmune diseases.

  15. Related B cell clones populate the meninges and parenchyma of patients with multiple sclerosis.

    Science.gov (United States)

    Lovato, Laura; Willis, Simon N; Rodig, Scott J; Caron, Tyler; Almendinger, Stefany E; Howell, Owain W; Reynolds, Richard; O'Connor, Kevin C; Hafler, David A

    2011-02-01

    In the central nervous system of patients with multiple sclerosis, B cell aggregates populate the meninges, raising the central question as to whether these structures relate to the B cell infiltrates found in parenchymal lesions or instead, represent a separate central nervous system immune compartment. We characterized the repertoires derived from meningeal B cell aggregates and the corresponding parenchymal infiltrates from brain tissue derived primarily from patients with progressive multiple sclerosis. The majority of expanded antigen-experienced B cell clones derived from meningeal aggregates were also present in the parenchyma. We extended this investigation to include 20 grey matter specimens containing meninges, 26 inflammatory plaques, 19 areas of normal appearing white matter and cerebral spinal fluid. Analysis of 1833 B cell receptor heavy chain variable region sequences demonstrated that antigen-experienced clones were consistently shared among these distinct compartments. This study establishes a relationship between extraparenchymal lymphoid tissue and parenchymal infiltrates and defines the arrangement of B cell clones that populate the central nervous system of patients with multiple sclerosis.

  16. Universal cytotoxic activity of a HTLV-1 Tax-specific T cell clone from an HLA-A*24:02⁺ patient with adult T-cell leukemia against a variety of HTLV-I-infected T-cells.

    Science.gov (United States)

    Tanaka, Yukie; Yamazaki, Rie; Terasako-Saito, Kiriko; Nakasone, Hideki; Akahoshi, Yu; Nakano, Hirofumi; Ugai, Tomotaka; Wada, Hidenori; Yamasaki, Ryoko; Ishihara, Yuko; Kawamura, Koji; Sakamoto, Kana; Ashizawa, Masahiro; Sato, Miki; Kimura, Shun-ichi; Kikuchi, Misato; Kako, Shinichi; Kanda, Junya; Tanihara, Aki; Nishida, Junji; Kanda, Yoshinobu

    2014-01-01

    Adult T cell leukemia/lymphoma (ATL) is an aggressive mature T cell malignancy that is causally associated with human T cell lymphotropic virus type 1 (HTLV-1) infection. The HTLV-1 regulatory protein Tax aggressively accelerates the proliferation of host cells and is also an important target antigen for CD8(+) cytotoxic T cells (CTLs). We previously reported that several predominant HLA-A*24:02-restricted HTLV-1 Tax301-309-specific CTL clones commonly expressed a particular amino acid sequence motif (P-D-R) in complementarity-determining region 3 of T-cell receptor (TCR)-β chain among unrelated ATL patients who underwent allogeneic stem cell transplantation (allo-HSCT). Furthermore, a PDR-motif(+) CTL clone persistently existed in a long-term survivor as a central CTL clone with strong CTL activities after HSCT. Although a larger analysis of the relationship between PDR-motif(+) CTLs and the clinical course is required, the expression of PDR-motif(+) TCR on CD8(+) T cells may play a critical role in the management of anti-HTLV-1 activities for HLA-A24:02(+) ATL patients. Therefore, in this study, we prepared an HTLV-1 Tax301-309 peptide-specific CTL clone (HT-9) expressing PDR-motif(+) TCR isolated from a long-term survivor after HSCT, and evaluated its CTL activity against a variety of HTLV-1-infected T-cells from HLA-A*24:02(+) ATL patients. Before the assay of CTL function, we confirmed that HT-9 expressed less-differentiated effector-memory phenotypes (CD45RA(-)CCR7(-)CD27(+)CD28(+/-)CD57(+/-)) and T-cell exhaustion marker PD-1(+). In assays of CTL function, HT-9 recognized HTLV-1 Tax in an HLA-restricted fashion and demonstrated strong CTL activities against a variety of HTLV-1-infected T-cells from HLA-A*24:02(+) ATL patients regardless of whether the sources were autologous or allogeneic, but not normal cells. These data indicate that PDR-motif(+) TCR could be an important TCR candidate for TCR-gene immunotherapy for HLA-A24:02(+) ATL patients, provided

  17. Isolation of hypoxanthine phosphoribosyltransferase-defective mutants in Chinese hamster V79 cells by tritium suicide

    International Nuclear Information System (INIS)

    Bryant, R.E.; Schauer, I.E.; Hatcher, D.G.

    1981-01-01

    Tritium suicide was shown to be a highly efficient method for isolating mutants defective in hypoxanthine incorporation in the Chinese hamster lung of one kill cycle were used for the next kill cycle. The kill cycles involved incorporation of ( 3 H) hypoxanthine for 5 or 10 min, followed by storage of 3 H-labelled cells at -70 0 C for 4-10 days. 12 clones that survived the 3rd kill cycle were tested for incorporation of ( 3 H)hypoxanthine and all were found to be defective. At least 6 of the clones have defective hypoxanthine phosphoribosyltransferase (HPRT) activity. One mutant, H19, chosen for further characterization, had HPRT with a 13-fold elevation in apparent Ksub(m) for phosphoribosylpyrophosphate (PRPP). Thin-layer chromatography of cell extracts showed that this mutant was incapable of converting intracellular hypoxanthine to IMP or to other purine metabolites. In addition, H19 was resistant to 6-thioguanine. (orig.)

  18. Cloning and characterization of a cDNA encoding topoisomerase II in pea and analysis of its expression in relation to cell proliferation.

    Science.gov (United States)

    Reddy, M K; Nair, S; Tewari, K K; Mudgil, Y; Yadav, B S; Sopory, S K

    1999-09-01

    We have isolated and sequenced four overlapping cDNA clones to identify the full-length cDNA for topoisomerase II (PsTopII) from pea. Using degenerate primers, based on the conserved amino acid sequences of other eukaryotic type II topoisomerases, a 680 bp fragment was PCR-amplified with pea cDNA as template. This fragment was used as a probe to screen an oligo-dT-primed pea cDNA library. A partial cDNA clone was isolated that was truncated at the 3' end. RACE-PCR was employed to isolate the remaining portion of the gene. The total size of PsTopII is 4639 bp with an open reading frame of 4392 bp. The deduced amino acid sequence shows a strong homology to other eukaryotic topoisomerase II (topo II) at the N-terminus end. The topo II transcript was abundant in proliferative tissues. We also show that the level of topo II transcripts could be stimulated by exogenous application of growth factors that induced proliferation in vitro cultures. Light irradiation to etiolated tissue strongly stimulated the expression of topo II. These results suggest that topo II gene expression is up-regulated in response to light and hormones and correlates with cell proliferation. Besides, we have also isolated and analysed the 5'-flanking region of the pea TopII gene. This is first report on the isolation of a putative promoter for topoisomerase II from plants.

  19. Late post-irradiation phenomena in mammalain cell populations. Pt. 2. Intraclonal recovery in sublines isolated from X-irradiated L5178Y-S cell populations

    International Nuclear Information System (INIS)

    Beer, J.Z.

    1975-01-01

    Clonal analysis of L5178Y-S cell populations irradiated with 300 rads of X-rays indicates occurence of cell sublines with considerably prolonged mean doubling times up to 22 h as compared to 10-11 h for control. Subsequent observations of growth of the handicapped sublines derived from single cells showed capability of all more than 100 studied sublines to recover normal proliferative activity. This process of intraclonal recovery required in many cases longer periods of time, corresponding to many tens, sometimes more than 200, generations. Late intraclonal recovery was further analysed by subcloning. It was found that although cytochemically assayed viability of the handicapped sublines was normal, cloning efficiency strongly depended on the stage of the recovery process. The recovery processes occuring in clones isolated from irradiated cell populations were compared with analogous processes occuring in slowly growing sublines isolated from non-irradiated cell cultures. Marked differences in kinetics of these processes show that either they are different in sublines derived from irradiated and non-irradiated cell populations or that the mechanisms of the late intraclonal recovery are affected by radiation. The results presented allow to conclude that gradual post-irradiation recovery of growth depends primarily on formation, in the developing populations, of cells with higher proliferative activities. Possible nature of the recovery processes is discussed in the light of available information on mammalian somatic cell variants with altered drug or temperature sensitivity, or with nutritional requirements. A sequence is proposed of changes leading from radiation-induced disturbance of the normably existing equilibrium between three basic cell subpopulations to ultimate restoration of this equilibrium. (author)

  20. Molecular cloning of a mouse DNA repair gene that complements the defect of group-A xeroderma pigmentosum

    International Nuclear Information System (INIS)

    Tanaka, K.; Satokata, I.; Ogita, Z.; Uchida, T.; Okada, Y.

    1989-01-01

    For isolation of the gene responsible for xeroderma pigmentosum (XP) complementation group A, plasmid pSV2gpt and genomic DNA from a mouse embryo were cotransfected into XP2OSSV cells, a group-A XP cell line. Two primary UV-resistant XP transfectants were isolated from about 1.6 X 10(5) pSV2gpt-transformed XP colonies. pSV2gpt and genomic DNA from the primary transfectants were again cotransfected into XP2OSSV cells and a secondary UV-resistant XP transfectant was obtained by screening about 4.8 X 10(5) pSV2gpt-transformed XP colonies. The secondary transfectant retained fewer mouse repetitive sequences. A mouse gene that complements the defect of XP2OSSV cells was cloned into an EMBL3 vector from the genome of a secondary transfectant. Transfections of the cloned DNA also conferred UV resistance on another group-A XP cell line but not on XP cell lines of group C, D, F, or G. Northern blot analysis of poly(A)+ RNA with a subfragment of cloned mouse DNA repair gene as the probe revealed that an approximately 1.0 kilobase mRNA was transcribed in the donor mouse embryo and secondary transfectant, and approximately 1.0- and approximately 1.3-kilobase mRNAs were transcribed in normal human cells, but none of these mRNAs was detected in three strains of group-A XP cells. These results suggest that the cloned DNA repair gene is specific for group-A XP and may be the mouse homologue of the group-A XP human gene

  1. Developments in stem cell research and therapeutic cloning: Islamic ethical positions, a review.

    Science.gov (United States)

    Fadel, Hossam E

    2012-03-01

    Stem cell research is very promising. The use of human embryos has been confronted with objections based on ethical and religious positions. The recent production of reprogrammed adult (induced pluripotent) cells does not - in the opinion of scientists - reduce the need to continue human embryonic stem cell research. So the debate continues. Islam always encouraged scientific research, particularly research directed toward finding cures for human disease. Based on the expectation of potential benefits, Islamic teachings permit and support human embryonic stem cell research. The majority of Muslim scholars also support therapeutic cloning. This permissibility is conditional on the use of supernumerary early pre-embryos which are obtained during infertility treatment in vitro fertilization (IVF) clinics. The early pre-embryos are considered in Islamic jurisprudence as worthy of respect but do not have the full sanctity offered to the embryo after implantation in the uterus and especially after ensoulment. In this paper the Islamic positions regarding human embryonic stem cell research and therapeutic cloning are reviewed in some detail, whereas positions in other religious traditions are mentioned only briefly. The status of human embryonic stem cell research and therapeutic cloning in different countries, including the USA and especially in Muslim countries, is discussed. © 2010 Blackwell Publishing Ltd.

  2. Progenitor cells for regenerative medicine and consequences of ART and cloning-associated epimutations.

    Science.gov (United States)

    Laprise, Shari L

    2010-06-01

    The "holy grail" of regenerative medicine is the identification of an undifferentiated progenitor cell that is pluripotent, patient specific, and ethically unambiguous. Such a progenitor cell must also be able to differentiate into functional, transplantable tissue, while avoiding the risks of immune rejection. With reports detailing aberrant genomic imprinting associated with assisted reproductive technologies (ART) and reproductive cloning, the idea that human embryonic stem cells (hESCs) derived from surplus in vitro fertilized embryos or nuclear transfer ESCs (ntESCs) harvested from cloned embryos may harbor dangerous epigenetic errors has gained attention. Various progenitor cell sources have been proposed for human therapy, from hESCs to ntESCs, and from adult stem cells to induced pluripotent stem cells (iPS and piPS cells). This review highlights the advantages and disadvantages of each of these technologies, with particular emphasis on epigenetic stability.

  3. Clone DB: an integrated NCBI resource for clone-associated data

    Science.gov (United States)

    Schneider, Valerie A.; Chen, Hsiu-Chuan; Clausen, Cliff; Meric, Peter A.; Zhou, Zhigang; Bouk, Nathan; Husain, Nora; Maglott, Donna R.; Church, Deanna M.

    2013-01-01

    The National Center for Biotechnology Information (NCBI) Clone DB (http://www.ncbi.nlm.nih.gov/clone/) is an integrated resource providing information about and facilitating access to clones, which serve as valuable research reagents in many fields, including genome sequencing and variation analysis. Clone DB represents an expansion and replacement of the former NCBI Clone Registry and has records for genomic and cell-based libraries and clones representing more than 100 different eukaryotic taxa. Records provide details of library construction, associated sequences, map positions and information about resource distribution. Clone DB is indexed in the NCBI Entrez system and can be queried by fields that include organism, clone name, gene name and sequence identifier. Whenever possible, genomic clones are mapped to reference assemblies and their map positions provided in clone records. Clones mapping to specific genomic regions can also be searched for using the NCBI Clone Finder tool, which accepts queries based on sequence coordinates or features such as gene or transcript names. Clone DB makes reports of library, clone and placement data on its FTP site available for download. With Clone DB, users now have available to them a centralized resource that provides them with the tools they will need to make use of these important research reagents. PMID:23193260

  4. Growth of single T cells and single thymocytes in a high cloning efficiency filler-cell free microculture system.

    Science.gov (United States)

    Chen, W F; Ewing, T; Scollay, R; Shortman, K

    1988-01-01

    A high cloning-efficiency microculture system is described in which single T cells, stimulated to divide by phorbol ester and calcium ionophore, grow rapidly under the influence of purified growth factors in the absence of other cells. The kinetics of clonal growth has been monitored over a five day period by phase-contrast microscopy. Mature peripheral T cells, and mature subpopulations from the thymus, responded with a cloning efficiency over 80%; they required IL-2 as a minimum but several other factors enhanced growth. Ly2+L3T4- thymocytes (mean doubling time 10.4 hr) grew more rapidly than Ly2-L3T4+ thymocytes (mean doubling time 15.2 hr). Early (Ly2-L3T4-) thymocytes responded with a cloning efficiency of 60%; their efficient growth was dependent on both IL-1 and IL-2. The typical Ly2+L3T4+ cortical thymocyte did not grow under these conditions.

  5. Cloning, expression, and enzymatic activity evaluation of cholesterol oxidase gene isolated from a native Rhodococcus sp.

    Directory of Open Access Journals (Sweden)

    Hamed Esmaeil Lashgarian

    2016-10-01

    Full Text Available Cholesterol oxidase (CHO is one of the valuable enzymes that play an important role in: measurement of serum cholesterol, food industry as a biocatalyst and agriculture as a biological larvicide. This enzyme was produced by several bacterial strains. Wild type enzyme produced by Rhodococcus sp. secret two forms of CHO enzyme: extra cellular and membrane bound type which its amount is low and unstable. The goal of the study was cloning, expression, and enzymatic activity evaluation of cholesterol oxidase gene isolated from a native Rhodococcus sp. CHO gene was isolated from native bacteria and cloned into pET23a. In the next step, the construct was expressed in E.coli BL21 and induced by different concentration of IPTG ranges from 0.1 - 0.9 mM. This gene contains 1642 bp and encodes a protein consists of 533 amino acids. It has about 96 % homology with CHO gene isolated from Rhodococcus equi. The high expression was obtained in 0.5 mM concentration of IPTG after 4 hour induction. This recombinant enzyme had a molecular weight of 55 kDa, that secretion of intra cellular type is much more than extracellular form. The optimum pH and temperature conditions for the recombinant enzyme were 7.5 and 45°C, respectively. CHO enzyme obtained from Rhodococcus sp. is a cheap enzyme with medical and industrial applications that can be produced easily and purified in large scale with simple methods.

  6. Isolation and characterization of full-length cDNA clones coding for cholinesterase from fetal human tissues

    International Nuclear Information System (INIS)

    Prody, C.A.; Zevin-Sonkin, D.; Gnatt, A.; Goldberg, O.; Soreq, H.

    1987-01-01

    To study the primary structure and regulation of human cholinesterases, oligodeoxynucleotide probes were prepared according to a consensus peptide sequence present in the active site of both human serum pseudocholinesterase and Torpedo electric organ true acetylcholinesterase. Using these probes, the authors isolated several cDNA clones from λgt10 libraries of fetal brain and liver origins. These include 2.4-kilobase cDNA clones that code for a polypeptide containing a putative signal peptide and the N-terminal, active site, and C-terminal peptides of human BtChoEase, suggesting that they code either for BtChoEase itself or for a very similar but distinct fetal form of cholinesterase. In RNA blots of poly(A) + RNA from the cholinesterase-producing fetal brain and liver, these cDNAs hybridized with a single 2.5-kilobase band. Blot hybridization to human genomic DNA revealed that these fetal BtChoEase cDNA clones hybridize with DNA fragments of the total length of 17.5 kilobases, and signal intensities indicated that these sequences are not present in many copies. Both the cDNA-encoded protein and its nucleotide sequence display striking homology to parallel sequences published for Torpedo AcChoEase. These finding demonstrate extensive homologies between the fetal BtChoEase encoded by these clones and other cholinesterases of various forms and species

  7. Cloning of transgenic tobacco BY-2 cells; an efficient method to analyse and reduce high natural heterogeneity of transgene expression.

    Science.gov (United States)

    Nocarova, Eva; Fischer, Lukas

    2009-04-22

    Phenotypic characterization of transgenic cell lines, frequently used in plant biology studies, is complicated because transgene expression in individual cells is often heterogeneous and unstable. To identify the sources and to reduce this heterogeneity, we transformed tobacco (Nicotiana tabacum L.) BY-2 cells with a gene encoding green fluorescent protein (GFP) using Agrobacterium tumefaciens, and then introduced a simple cloning procedure to generate cell lines derived from the individual transformed cells. Expression of the transgene was monitored by analysing GFP fluorescence in the cloned lines and also in lines obtained directly after transformation. The majority ( approximately 90%) of suspension culture lines derived from calli that were obtained directly from transformation consisted of cells with various levels of GFP fluorescence. In contrast, nearly 50% of lines generated by cloning cells from the primary heterogeneous suspensions consisted of cells with homogenous GFP fluorescence. The rest of the lines exhibited "permanent heterogeneity" that could not be resolved by cloning. The extent of fluorescence heterogeneity often varied, even among genetically identical clones derived from the primary transformed lines. In contrast, the offspring of subsequent cloning of the cloned lines was uniform, showing GFP fluorescence intensity and heterogeneity that corresponded to the original clone. The results demonstrate that, besides genetic heterogeneity detected in some lines, the primary lines often contained a mixture of epigenetically different cells that could be separated by cloning. This indicates that a single integration event frequently results in various heritable expression patterns, which are probably accidental and become stabilized in the offspring of the primary transformed cells early after the integration event. Because heterogeneity in transgene expression has proven to be a serious problem, it is highly advisable to use transgenes tagged with

  8. Cloning and sequence analysis of cDNA coding for rat nucleolar protein C23

    International Nuclear Information System (INIS)

    Ghaffari, S.H.; Olson, M.O.J.

    1986-01-01

    Using synthetic oligonucleotides as primers and probes, the authors have isolated and sequenced cDNA clones encoding protein C23, a putative nucleolus organizer protein. Poly(A + ) RNA was isolated from rat Novikoff hepatoma cells and enriched in C23 mRNA by sucrose density gradient ultracentrifugation. Two deoxyoligonuleotides, a 48- and a 27-mer, were synthesized on the basis of amino acid sequence from the C-terminal half of protein C23 and cDNA sequence data from CHO cell protein. The 48-mer was used a primer for synthesis of cDNA which was then inserted into plasmid pUC9. Transformed bacterial colonies were screened by hybridization with 32 P labeled 27-mer. Two clones among 5000 gave a strong positive signal. Plasmid DNAs from these clones were purified and characterized by blotting and nucleotide sequence analysis. The length of C23 mRNA was estimated to be 3200 bases in a northern blot analysis. The sequence of a 267 b.p. insert shows high homology with the CHO cDNA with only 9 nucleotide differences and an identical amino acid sequence. These studies indicate that this region of the protein is highly conserved

  9. Bovine viral diarrhea virus: molecular cloning of genomic RNA and its diagnostic application

    International Nuclear Information System (INIS)

    Brock, K.V.

    1987-01-01

    Molecular cloning of a field isolate of bovine viral diarrhea virus (BVDV) strain 72 RNA was done in this study. The sensitivity and specificity of cloned cDNA sequences in hybridization assays with various BVDV strains were determined. cDNA was synthesized from polyadenylated BVDV RNA templates with oligo-dT primers, reverse transcriptase, and DNA polymerase I. The newly synthesized double-stranded BVDV cDNA was C-tailed with terminal deoxytransferase and annealed into G-tailed, Pst-1-cut pUC9 plasmid. Escherichia coli was transformed with the recombinant plasmids and a library of approximately 200 BVDV specific cDNA clones varying in length from 0.5 to 2.6 kilobases were isolated. The sensitivity and specificity of hybridization between the labelled cDNA and BVDV target sequences were determined. Cloned BVDV sequences were isolated from pUC9 plasmid DNA and labelled with 32 P by nick translation. The detection limit by dot blot hybridization assay was 20 pg of purified genomic BVDV RNA. cDNA hybridization probes were specific for all strains of BVDV tested, regardless of whether they were noncytopathic and cytopathic, but did not hybridize with heterologous bovine viruses tested. Probes did not hybridize with uninfected cell culture or cellular RNA. Hybridization probes were at least as sensitive as infectivity assays in detecting homologous virus

  10. Persistence of collagen type II-specific T-cell clones in the synovial membrane of a patient with rheumatoid arthritis

    International Nuclear Information System (INIS)

    Londei, M.; Savill, C.M.; Verhoef, A.; Brennan, F.; Leech, Z.A.; Feldmann, M.; Duance, V.; Maini, R.N.

    1989-01-01

    Rheumatoid arthritis is an autoimmune disease characterized by T-cell infiltration of the synovium of joints. Analysis of the phenotype and antigen specificity of the infiltrating cells may thus provide insight into the pathogenesis of rheumatoid arthritis. T cells were cloned with interleukin 2, a procedure that selects for in vivo-activated cells. All clones had the CD4 CDW29 phenotype. Their antigen specificity was tested by using a panel of candidate joint autoantigens. Four of 17 reacted against autologous blood mononuclear cells. Two clones proliferated in response to collagen type II. After 21 months, another set of clones was derived from synovial tissue of the same joint. One of eight clones tested showed a strong proliferative response against collagen type II. The uncloned synovial T cells of a third operation from another joint also responded to collagen type II. The persistence of collagen type II-specific T cells in active rheumatoid joints over a period of 3 years suggests that collagen type II could be one of the autoantigens involved in perpetuating the inflammatory process in rheumatoid arthritis

  11. Isolation, propagation, and titration of human immunodeficiency virus type 1 from peripheral blood of infected individuals

    NARCIS (Netherlands)

    Schuitemaker, Hanneke; Kootstra, Neeltje A.

    2005-01-01

    HIV-1 can be isolated from peripheral blood mononuclear cells and is easily propagated on primary cells in vitro. Here we describe the method for bulk isolation of the HIV-1 quasispecies and a limiting dilution virus isolation protocol by which single coexisting clones can be obtained. In addition,

  12. Improvement of cloning efficiency in minipigs using post-thawed donor cells treated with roscovitine.

    Science.gov (United States)

    Hwang, Seongsoo; Oh, Keon Bong; Kwon, Dae-Jin; Ock, Sun-A; Lee, Jeong-Woong; Im, Gi-Sun; Lee, Sung-Soo; Lee, Kichoon; Park, Jin-Ki

    2013-11-01

    Massachusetts General Hospital miniature pigs (MGH minipigs) have been established for organ transplantation studies across the homozygous major histocompatibility complex, but cloning efficiency of MGH minipigs is extremely low. This study was designed to increase the productivity of MGH minipigs by nuclear transfer of post-thaw donor cells after 1 h co-incubation with roscovitine. The MGH minipig cells were genetically modified with GT KO (alpha1,3-galactosyltransferase knock-out) and hCD46 KI (human CD46 knock-in) and used as donor cells. The GT KO/hCD46 KI donor cells were cultured for either 3 days (control group) or 1 h after thawing with 15 μM roscovitine (experimental group) prior to the nuclear transfer. The relative percentage of the transgenic donor cells that entered into G0/G1 was 93.7 % (±2.54). This was different from the donor cells cultured for 1 h with the roscovitine-treated group (84.6 % ±4.6) (P cloning efficiency ranged from 0.74 to 2.54 %. In conclusion, gene-modified donor cells can be used for cloning of MGH minipigs if the cells are post-thawed and treated with roscovitine for 1 h prior to nuclear transfer.

  13. A method for autoradiographic studies of single clones of plaque forming cells

    International Nuclear Information System (INIS)

    Andersen, V.; Lefkovits, I.; Rigshospitalet, Copenhagen

    1977-01-01

    By limiting dilution of B lymphocytes from spleens of immunized mice, microcultures were obtained that contained only one clone of plaque forming cells (PFC). The cultured cells were labelled with [ 14 C]thymidine for varying period of time. Plaques were obtained in monolayers of sheep erythrocytes in plastic dishes. After fixation with glutaraldehyde, the bottoms of the dishes were stripped off and autoradiograms prepared. By this method, it is possible to determine the proportion of labelled PFC within a given clone and to quantitate the incorporation of label. The method described can be applied to study the incorporation of other labelled molecules and for cytochemical investigations

  14. Can mammalian cloning combined with embryonic stem cell technologies be used to treat human diseases?

    Science.gov (United States)

    Hadjantonakis, Anna-Katerina; Papaioannou, Virginia E

    2002-01-01

    Cloning is commonly perceived as a means of generating genetically identical individuals, but it can also be used to obtain genetically matched embryo-derived stem cells, which could potentially be used in the treatment of patients. A recent report offers the first 'proof of principle' of such cloning for therapeutic purposes, referred to as nuclear transplantation to produce stem cells for autologous transplantation. PMID:12186652

  15. Evidence that certain clones of Campylobacter jejuni persist during successive broiler flock rotations

    DEFF Research Database (Denmark)

    Petersen, L.; Wedderkopp, A.

    2001-01-01

    selected. Twelve broiler houses located on 10 farms were included in the study. The C,jejuni isolates collected from the selected houses during the surveillance were typed using fla typing and macrorestriction profiling (MRP), and a subset of the isolates, representing each of the identified clones...... (7 of 13) had fla type 1/1, but MRPs distinguished between isolates from different houses, and fla type 1/1 clones belonged to different serotypes, Seven houses carried persistent clones that covered an interval of at least four broiler flock rotations, or at least one half year. The dominant fla...... with recurrent Campylobacter problems. The MRPs of clones belonging to fla type 1/1 serotype O:2 isolated from persistently infected flocks shared a high percentage of bands compared to the remaining isolates, indicating that some clones that have the ability to cause persistent infections in broiler farms...

  16. Development and Characterization of Recombinant Virus Generated from a New World Zika Virus Infectious Clone.

    Science.gov (United States)

    Weger-Lucarelli, James; Duggal, Nisha K; Bullard-Feibelman, Kristen; Veselinovic, Milena; Romo, Hannah; Nguyen, Chilinh; Rückert, Claudia; Brault, Aaron C; Bowen, Richard A; Stenglein, Mark; Geiss, Brian J; Ebel, Gregory D

    2017-01-01

    Zika virus (ZIKV; family Flaviviridae, genus Flavivirus) is a rapidly expanding global pathogen that has been associated with severe clinical manifestations, including devastating neurological disease in infants. There are currently no molecular clones of a New World ZIKV available that lack significant attenuation, hindering progress toward understanding determinants of transmission and pathogenesis. Here we report the development and characterization of a novel ZIKV reverse genetics system based on a 2015 isolate from Puerto Rico (PRVABC59). We generated a two-plasmid infectious clone system from which infectious virus was rescued that replicates in human and mosquito cells with growth kinetics representative of wild-type ZIKV. Infectious clone-derived virus initiated infection and transmission rates in Aedes aegypti mosquitoes comparable to those of the primary isolate and displayed similar pathogenesis in AG129 mice. This infectious clone system provides a valuable resource to the research community to explore ZIKV molecular biology, vaccine development, antiviral development, diagnostics, vector competence, and disease pathogenesis. ZIKV is a rapidly spreading mosquito-borne pathogen that has been linked to Guillain-Barré syndrome in adults and congenital microcephaly in developing fetuses and infants. ZIKV can also be sexually transmitted. The viral molecular determinants of any of these phenotypes are not well understood. There is no reverse genetics system available for the current epidemic virus that will allow researchers to study ZIKV immunity, develop novel vaccines, or develop antiviral drugs. Here we provide a novel infectious clone system generated from a recent ZIKV isolated from a patient infected in Puerto Rico. This infectious clone produces virus with in vitro and in vivo characteristics similar to those of the primary isolate, providing a critical tool to study ZIKV infection and disease. Copyright © 2016 American Society for Microbiology.

  17. Molecular cloning of L-methylmalonyl-CoA mutase: Gene transfer and analysis of mut cell lines

    International Nuclear Information System (INIS)

    Ledley, F.D.; Lumetta, M.; Nguyen, P.N.; Kolhouse, J.F.; Allen, R.H.

    1988-01-01

    L-Methylmalonyl-CoA mutase (MCM, EC 5.4.99.2) is a mitochondrial adenosylcobalamin-requiring enzyme that catalyzes the isomerization of L-methylmalonyl-CoA to succinyl-CoA. This enzyme is deficient in methylmalonic acidemia, an often fatal disorder of organic acid metabolism. Antibody against human placental MCM was used to screen human placenta and liver cDNA expression libraries for MCM cDNA clones. One clone expressed epitopes that could affinity-purify antibodies against MCM. A cDNA corresponding in length to the mRNA was obtained and introduced into COS cells by DNA-mediated gene transfer. Cells transformed with this clone expressed increased levels of MCM enzymatic activity. RNA blot analysis of cells genetically deficient in MCM indicates that several deficient cell lines have a specific decrease in the amount of hybridizable mRNA. These data confirm the authenticity of the MCM cDNA clone, establish the feasibility of constituting MCM activity by gene transfer for biochemical analysis and gene therapy, and provide a preliminary picture of the genotypic spectrum underlying MCM deficiency

  18. Isolation and characterization of cDNA clones for human erythrocyte β-spectrin

    International Nuclear Information System (INIS)

    Prchal, J.T.; Morley, B.J.; Yoon, S.H.; Coetzer, T.L.; Palek, J.; Conboy, J.G.; Kan, Y.W.

    1987-01-01

    Spectrin is an important structural component of the membrane skeleton that underlies and supports the erythrocyte plasma membrane. It is composed of nonidentical α (M/sub r/ 240,000) and β (M/sub r/ 220,000) subunits, each of which contains multiple homologous 106-amino acid segments. The authors report here the isolation and characterization of a human erythroid-specific β-spectrin cDNA clone that encodes parts of the β-9 through β-12 repeat segments. This cDNA was used as a hybridization probe to assign the β-spectrin gene to human chromosome 14 and to begin molecular analysis of the gene and its mRNA transcripts. RNA transfer blot analysis showed that the reticulocyte β-spectrin mRNA is 7.8 kilobases in length. Southern blot analysis of genomic DNA revealed the presence of restriction fragment length polymorphisms (RFLPs) within the β-spectrin gene locus. The isolation of human spectrin cDNA probes and the identification of closely linked RFLPs will facilitate analysis of mutant spectrin genes causing congenital hemolytic anemias associated with quantitative and qualitative spectrin abnormalities

  19. IgE production by normal human B cells induced by alloreactive T cell clones is mediated by IL-4 and suppressed by IFN-gamma

    NARCIS (Netherlands)

    Pène, J.; Rousset, F.; Brière, F.; Chrétien, I.; Paliard, X.; Banchereau, J.; Spits, H.; de Vries, J. E.

    1988-01-01

    Seven T cell clones were established from mixed leukocyte cultures in which PBMC from two healthy donors and from one patient suffering from the hyper-IgE syndrome were stimulated by the irradiated EBV-transformed B cell lines JY or UD53. Five of seven T cell clones, after activation by

  20. Cloning, sequencing, and expression of cDNA for human β-glucuronidase

    International Nuclear Information System (INIS)

    Oshima, A.; Kyle, J.W.; Miller, R.D.

    1987-01-01

    The authors report here the cDNA sequence for human placental β-glucuronidase (β-D-glucuronoside glucuronosohydrolase, EC 3.2.1.31) and demonstrate expression of the human enzyme in transfected COS cells. They also sequenced a partial cDNA clone from human fibroblasts that contained a 153-base-pair deletion within the coding sequence and found a second type of cDNA clone from placenta that contained the same deletion. Nuclease S1 mapping studies demonstrated two types of mRNAs in human placenta that corresponded to the two types of cDNA clones isolated. The NH 2 -terminal amino acid sequence determined for human spleen β-glucuronidase agreed with that inferred from the DNA sequence of the two placental clones, beginning at amino acid 23, suggesting a cleaved signal sequence of 22 amino acids. When transfected into COS cells, plasmids containing either placental clone expressed an immunoprecipitable protein that contained N-linked oligosaccharides as evidenced by sensitivity to endoglycosidase F. However, only transfection with the clone containing the 153-base-pair segment led to expression of human β-glucuronidase activity. These studies provide the sequence for the full-length cDNA for human β-glucuronidase, demonstrate the existence of two populations of mRNA for β-glucuronidase in human placenta, only one of which specifies a catalytically active enzyme, and illustrate the importance of expression studies in verifying that a cDNA is functionally full-length

  1. Characterization of a mutant rat kangaroo cell line with alterations in the cell cycle and DNA repair

    OpenAIRE

    Miyaji, E.N.; Johnson, R.T.; Downes, C.S.; Eveno, E.; Mezzina, M.; Sarasin, A.; Menck, C.F.M.

    2000-01-01

    Using a positive selection system for isolating DNA replication and repair related mutants, we isolated a clone from a rat kangaroo cell line (PtK2) that has increased sensitivity to UV light. Characterization of this clone indicated normal post-replication repair after UV irradiation, and normal removal rates of cyclobutane pyrimidine dimers and pyrimidine(6-4)pyrimidone photoproducts by excision repair. However, this cell line has decreased ability to make early incisions on damaged DNA, po...

  2. Artificial cloning of domestic animals.

    Science.gov (United States)

    Keefer, Carol L

    2015-07-21

    Domestic animals can be cloned using techniques such as embryo splitting and nuclear transfer to produce genetically identical individuals. Although embryo splitting is limited to the production of only a few identical individuals, nuclear transfer of donor nuclei into recipient oocytes, whose own nuclear DNA has been removed, can result in large numbers of identical individuals. Moreover, clones can be produced using donor cells from sterile animals, such as steers and geldings, and, unlike their genetic source, these clones are fertile. In reality, due to low efficiencies and the high costs of cloning domestic species, only a limited number of identical individuals are generally produced, and these clones are primarily used as breed stock. In addition to providing a means of rescuing and propagating valuable genetics, somatic cell nuclear transfer (SCNT) research has contributed knowledge that has led to the direct reprogramming of cells (e.g., to induce pluripotent stem cells) and a better understanding of epigenetic regulation during embryonic development. In this review, I provide a broad overview of the historical development of cloning in domestic animals, of its application to the propagation of livestock and transgenic animal production, and of its scientific promise for advancing basic research.

  3. Differential responses to radiation and hyperthermia of cloned cell lines derived from a single human melanoma xenograft

    International Nuclear Information System (INIS)

    Rofstad, E.K.; Brustad, T.

    1984-01-01

    One uncloned and five cloned cell lines were derived from a single human melanoma xenograft. Cells from passages 7-12 were exposed to either radiation or hyperthermia (42.5 0 C, pH = 7.4) under aerobic conditions and the colony forming ability of the cells was assayed in soft agar. The five cloned lines showed individual and characteristic responses to radiation as well as to hyperthermia. The variation in the response to radiation was mainly reflected in the size of the shoulders of the survival curves rather than in the D 0 -values. The variation in the response to hyperthermia was mainly reflected in the terminal slopes of the survival curves. The survival curve of cells from the uncloned line, both when exposed to radiation and hyperthermia, was positioned in the midst of those of the cloned lines. The response of the cloned lines to radiation did not correlate with the response to hyperthermia, indicating that tumor cell subpopulations which are resistant to radiation may respond well to hyperthermia

  4. Identification of a new geographically widespread multiresistant Acinetobacter baumannii clone from European hospitals.

    Science.gov (United States)

    van Dessel, Helke; Dijkshoorn, Lenie; van der Reijden, Tanny; Bakker, Nancy; Paauw, Armand; van den Broek, Peterhans; Verhoef, Jan; Brisse, Sylvain

    2004-03-01

    The aim of the study was to investigate the genetic diversity of Acinetobacter baumannii clinical strains that had previously been allocated to three major groups based on automated ribotyping. Forty-seven isolates from European hospitals and one isolate from a South African hospital, geographically representative of the three ribogroups (ribogroups 1, 2 and 3 with 10, 23 and 15 isolates, respectively), were analysed using the highly discriminatory fingerprinting methods AFLP and pulsed-field gel electrophoresis (PFGE). Based on AFLP data, the isolates clustered into three main groups, each corresponding to one ribogroup. Inclusion of reference strains of the previously described clones I and II, responsible for outbreaks in northwestern European hospitals, showed that ribogroups 1 and 2 correspond to clones I and II, respectively, whereas ribogroup 3 apparently represents a new clone. This clone III was found in France, The Netherlands, Italy and Spain. Clones I and II were not limited to northwestern European countries, as they were also recovered from Spain, South Africa, Poland and Italy (clone I) and from Spain, Portugal, South Africa, France, Greece and Turkey (clone II). Combined AFLP and PFGE data showed intraclonal diversity and led to the distinction of 23 different genotypes. Three genotypes, two of them belonging to clone II and one to clone III, were found in different hospitals and may correspond to subsets of isolates with a more recent clonal relationship, which emphasizes the epidemic potential of these organisms.

  5. Expression of Two N1 Clones with Single Amino Acid Dissimilarity of Avian Influenza H5N1 Virus

    Directory of Open Access Journals (Sweden)

    RISZA HARTAWAN

    2012-12-01

    Full Text Available Two clones of N1 gene derived from isolate A/Dk/Tangerang/Bbalitvet-ACIAR-TE11/2007 (H5N1 exhibit single mismatch of amino acid sequence at position 242 that is threonine and methionine for the clone #3 and #5, respectively. In order to evaluate the effect of the amino acid substitution, these clones were inserted into two different expression vectors that are pEGFP-C1 and pcDNA-3.3 TOPO® TA cloning. Subsequently, the respective recombinant clones were transfected into eukaryotic cells, including CEF, RK13 and VERO using Lipofectamine ‘plus’ reagent. As a result, the clone #3 retaining atypical sequence showed lower expression level rather than the clone #15 in both vectors and all type of cells. The 3D conformational modelling revealed that the mutation occurs in the inner part of glycoprotein embedded within envelope or matrix. Therefore, the missense mutation seems has no effect on the antigenic properties of neuraminidase but this substitution by any means causes lethal mutagenesis in the individual gene expression by reducing level of protein transcript.

  6. Cloning and expression of cell wall acid invertase gene fragment ...

    African Journals Online (AJOL)

    ONOS

    2010-01-25

    Jan 25, 2010 ... intron. It had a high homology to previously cloned cell wall acid invertase genes in other plants by sequence .... Japan) in a final volume of 50 µl. The programs for ... The first strand of cDNA was synthesized by using SYBR ...

  7. Specific Schistosoma mansoni rat T cell clones. I. Generation and functional analysis in vitro and in vivo.

    Science.gov (United States)

    Pestel, J; Dissous, C; Dessaint, J P; Louis, J; Engers, H; Capron, A

    1985-06-01

    In an attempt to determine the role of schistosome-specific T cells in the immune mechanisms developed during schistosomiasis, Schistosoma mansoni-specific T cells and clones were generated in vitro and some of their functions analyzed in vitro and in vivo in the fischer rat model. The data presented here can be summarized as follows: a) Lymph node cells (LNC) from rats primed with the excretory/secretory antigens-incubation products (IPSm) of adult worms proliferate in vitro only in response to the homologous schistosome antigens and not to unrelated antigens (Ag) such as ovalbumin (OVA) or Dipetalonema viteae and Fasciola hepatica parasite extracts. b) After in vitro restimulation of the primed LNC population with IPSm in the presence of antigen-presenting cells (APC) and maintenance in IL 2-containing medium, the frequency of IPSm-specific T cells is increased and the T cells can be restimulated only in the presence of APC possessing the same major histocompatibility complex (MHC) antigens. c) Following appropriate limiting dilution assays (LDA) (1 cell/well), 10 IPSm-specific T cell clones were obtained, and two of four maintained in culture were tested for their helper activity because they expressed only the W3/13+ W3/25+ surface phenotypes. d) The two highly proliferating IPSm-specific T cell clones (G5 and E23) exhibit an IPSm-dependent helper activity, as shown by the increase in IgG production by IPSm-primed B cells. e) IPSm-T cell clone (G5) as well as IPSm-T cell lines when injected in S. mansoni-infested rats can exert an in vivo helper activity, which is characterized by an accelerated production of IgG antibodies specific for the previously identified 30 to 40 kilodaltons (kd) schistosomula surface antigens (Ag). As recent studies have demonstrated that rat monoclonal antibodies recognize some incubation products of adult S. mansoni as well as one of the 30 to 40 kd schistosomula surface antigens, and taking into account the fact that the T cell

  8. Genetic diversity of methicillin resistant Staphylococcus aureus strains isolated from burn patients in Iran: ST239-SCCmec III/t037 emerges as the major clone.

    Science.gov (United States)

    Goudarzi, Mehdi; Bahramian, Mahnaz; Satarzadeh Tabrizi, Mahboobeh; Udo, Edet E; Figueiredo, Agnes Marie Sá; Fazeli, Maryam; Goudarzi, Hossein

    2017-04-01

    Methicillin-resistant Staphylococcus aureus (MRSA) as a major cause of infection in health care, hospital and community settings is a global health concern. The purpose of this study was to determine the antibiotic susceptibility pattern and distribution of circulating molecular types of MRSA in a burn hospital in Tehran, the capital of Iran. During a 10-month study period, 106 Staphylococcus aureus isolates were assessed. Isolates were subjected to susceptibility testing using the disk diffusion method and Polymerase Chain Reaction (PCR) for detection of mecA, fem and nuc genes. The presence of PVL and tst encoding genes were determined by PCR method. All the MRSA isolates were genotyped by multilocus sequence typing (MLST), spa typing, SCCmec typing and agr typing. The presence of mecA gene was confirmed in all the Staphylococcus aureus isolates. Antimicrobial susceptibility testing revealed a high resistance rate (90.6%) to ampicillin, tetracycline, and erythromycin. The rates of resistance to remaining antibiotics tested varied between 18.9% and 84.9%. The high- level of resistance to mupirocin was confirmed in 19.8% of MRSA strains isolated from burn patients. Multi-drug resistance was observed in 90.6% of isolates. Sixteen of the 106 MRSA isolates (15.1%) harbored PVL-encoding genes. The majority of our MRSA strains carried SCCmec III (71.7%). ST239-SCCmec III/t037 (34%) was the most common genotype followed by ST239-SCCmec III/t030 (24.5%), ST15-SCCmec IV/t084 (15.1%), ST22-SCCmec IV/t790 (13.2%), and ST239-SCCmec III/t631 (13.2%). Mupirocin resistant MRSA isolates belonged to ST15-SCCmec IV/t084 (40%), ST22-SCCmec IV/t790 (23.3%), ST239-SCCmec III/t631 (20%), and ST239-SCCmec III/t030 (16.7%) clones. The results showed that genetically diverse strains of MRSA are circulating in our burn hospitals with relatively high prevalence of ST239-SCCmec III/t037 clone. The findings support the need for regular surveillance of MRSA to determine the distribution of

  9. Cloning of cDNA sequences of a progestin-regulated mRNA from MCF7 human breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Chalbos, D; Westley, B; Alibert, C; Rochefort, H

    1986-01-24

    A cDNA clone corresponding to an mRNA regulated by the progestin R5020, has been isolated by differential screening of a cDNA library from the MCF7 breast cancer cell line, which contains estrogen and progesterone receptors. This probe hybridized with a single species of poly A + RNA of 8-kb molecular weight as shown by Northern blot analysis and could also be used to total RNA preparation. This recombinant cone hybridized specifically to an mRNA coding for a 250,000 daltons protein when translated in vitro. This protein was identical to the 250 kDa progestin-regulated protein that the authors previously described as shown by immunoprecipitation with specific rabbit polyclonal antibodies. Dose-response curve and specificity studies show that the accumulation of the Pg8 mRNA and that of the 250-kDa protein was increased by 5 to 30-fold following progestin treatment and that this effect was mediated by the progesterone receptor. Time course of induction indicated that the accumulation of mRNA was rapid and preceded that of the protein. This is the first report on a cloned cDNA probe of progestin-regulated mRNA in human cell lines.

  10. Treatment of porcine donor cells and reconstructed embryos with the antioxidant melatonin enhances cloning efficiency.

    Science.gov (United States)

    Pang, Yun-Wei; An, Lei; Wang, Peng; Yu, Yong; Yin, Qiu-Dan; Wang, Xiao-Hong; Xin-Zhang; Qian-Zhang; Yang, Mei-Ling; Min-Guo; Wu, Zhong-Hong; Tian, Jian-Hui

    2013-05-01

    This study was conducted to investigate the effect of melatonin during the culture of donor cells and cloned embryos on the in vitro developmental competence and quality of cloned porcine embryos. At concentrations of 10(-6 )M or 10(-8) M, melatonin significantly enhanced the proliferation of porcine fetal fibroblasts (PFFs), and the blastocyst rate was significantly increased in the 10(-10) M melatonin-treated donor cell group. Cloned embryo development was also improved in embryo culture medium that was supplemented with 10(-9) M or 10(-12) M melatonin. When both donor cells and cloned embryos were treated with melatonin, the cleavage rate and total cell number of blastocysts were not significantly affected; however, the blastocyst rate was increased significantly (20.0% versus 11.7%). TUNEL assays showed that combined melatonin treatment reduced the rate of apoptotic nuclei (3.6% versus 6.1%). Gene expression analysis of the apoptosis-related genes BAX, BCL2L1, and p53 showed that the expression of BCL2L1 was significantly elevated 2.7-fold relative to the control group, while the expression of BAX and p53 was significantly decreased by 3.7-fold and 23.2-fold, respectively. In addition, we detected the expression of two melatonin receptors (MT1 and MT2) in PFFs but not in porcine cloned embryos. We conclude that exogenous melatonin enhances the development of porcine cloned embryos and improves embryo quality by inhibiting p53-mediated apoptotic pathway. The proliferation of PFFs may be mediated by receptor binding, but the beneficial effects of melatonin on embryonic development may be receptor-independent, possibly through melatonin's ability to directly scavenge free radicals. © 2012 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.

  11. Apoptosis Gene Hunting Using Retroviral Expression Cloning: Identification of Vacuolar ATPase Subunit E

    Directory of Open Access Journals (Sweden)

    Claire L. Anderson

    2003-01-01

    Full Text Available Over the past 10-15 years there has been an explosion of interest in apoptosis. The delayed realisation that cell death is an essential part of life for any multicellular organism has meant that, despite the recent and rapid developments of the last decade, the precise biochemical pathways involved in apoptosis remain incomplete and potentially novel genes may, as yet, remain undiscovered. The hunt is therefore on to bridge the remaining gaps in our knowledge. Our contribution to this research effort utilises a functional cloning approach to isolate important regulatory genes involved in apoptosis. This mini-review focuses on the use and advantages of a retroviral expression cloning strategy and describes the isolation and identification of one such potential apoptosis regulatory gene, namely that encoding vacuolar ATPase subunit E.

  12. Cloning of the Repertoire of Individual Plasmodium falciparum var Genes Using Transformation Associated Recombination (TAR)

    Science.gov (United States)

    Schmid, Christoph D.; Bühlmann, Tobias; Louis, Edward J.; Beck, Hans-Peter

    2011-01-01

    One of the major virulence factors of the malaria causing parasite is the Plasmodium falciparum encoded erythrocyte membrane protein 1 (PfEMP1). It is translocated to It the membrane of infected erythrocytes and expressed from approximately 60 var genes in a mutually exclusive manner. Switching of var genes allows the parasite to alter functional and antigenic properties of infected erythrocytes, to escape the immune defense and to establish chronic infections. We have developed an efficient method for isolating VAR genes from telomeric and other genome locations by adapting transformation-associated recombination (TAR) cloning, which can then be analyzed and sequenced. For this purpose, three plasmids each containing a homologous sequence representing the upstream regions of the group A, B, and C var genes and a sequence homologous to the conserved acidic terminal segment (ATS) of var genes were generated. Co-transfection with P. falciparum strain ITG2F6 genomic DNA in yeast cells yielded 200 TAR clones. The relative frequencies of clones from each group were not biased. Clones were screened by PCR, as well as Southern blotting, which revealed clones missed by PCR due to sequence mismatches with the primers. Selected clones were transformed into E. coli and further analyzed by RFLP and end sequencing. Physical analysis of 36 clones revealed 27 distinct types potentially representing 50% of the var gene repertoire. Three clones were selected for sequencing and assembled into single var gene containing contigs. This study demonstrates that it is possible to rapidly obtain the repertoire of var genes from P. falciparum within a single set of cloning experiments. This technique can be applied to individual isolates which will provide a detailed picture of the diversity of var genes in the field. This is a powerful tool to overcome the obstacles with cloning and assembly of multi-gene families by simultaneously cloning each member. PMID:21408186

  13. Establishment of a vascular endothelial cell-reactive type II NKT cell clone from a rat model of autoimmune vasculitis.

    Science.gov (United States)

    Iinuma, Chihiro; Waki, Masashi; Kawakami, Ai; Yamaguchi, Madoka; Tomaru, Utano; Sasaki, Naomi; Masuda, Sakiko; Matsui, Yuki; Iwasaki, Sari; Baba, Tomohisa; Kasahara, Masanori; Yoshiki, Takashi; Paletta, Daniel; Herrmann, Thomas; Ishizu, Akihiro

    2015-02-01

    We previously generated a rat model that spontaneously developed small vessel vasculitis (SVV). In this study, a T cell clone reactive with rat vascular endothelial cells (REC) was established and named VASC-1. Intravenous injection of VASC-1 induced SVV in normal recipients. VASC-1 was a TCRαβ/CD3-positive CD4/CD8 double-negative T cell clone with expression of NKG2D. The cytokine mRNA profile under unstimulated condition was positive for IL-4 and IFN-γ but negative for IL-2 and IL-10. After interaction with REC, the mRNA expression of IL-2, IL-5 and IL-6 was induced in VASC-1, which was inhibited by blocking of CD1d on the REC surface. Although the protein levels of these cytokines seemed to be lower than the detection limit in the culture medium, IFN-γ was detectable. The production of IFN-γ from the VASC-1 stimulated with LPS-pre-treated REC was inhibited by the CD1d blockade on the REC. These findings indicated VASC-1 as an NKT cell clone. The NKT cell pool includes two major subsets, namely types I and II. Type I NKT cells are characterized by expression of semi-invariant TCRs and the potential to bind to marine sponge-derived α-galactosylceramide (α-GalCer) loaded on CD1d; whereas, type II NKT cells do not manifest these characteristics. VASC-1 exhibited a usage of TCR other than the type I invariant TCR α chain and did not bind to α-GalCer-loaded CD1d; therefore, it was determined as a type II NKT cell clone. The collective evidence suggested that REC-reactive type II NKT cells could be involved in the pathogenesis of SVV in rats. © The Japanese Society for Immunology. 2014. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. Construction of a molecular clone of ovine enzootic nasal tumor virus.

    Science.gov (United States)

    Walsh, Scott R; Gerpe, María Carla Rosales; Wootton, Sarah K

    2016-12-30

    Enzootic nasal tumor virus (ENTV-1) is an ovine betaretrovirus that has been linked to enzootic nasal adenocarcinoma (ENA), a contagious tumor of the ethmoid turbinates of sheep. Transmission experiments performed using virus isolated from cell free nasal tumor homogenates suggest that ENTV-1 is the causative agent of ENA; however, this etiological relationship has not been conclusively proven due to the fact that the virus cannot be propagated in vitro nor is there an infectious molecular clone of the virus. Here we report construction of a molecular clone of ENTV-1 and demonstrate that transfection of this molecular clone into HEK 293T cells produces mature virus particles. Analysis of recombinant virus particles derived from the initial molecular clone revealed a defect in the proteolytic processing of Gag; however, this defect could be corrected by co-expression of the Gag-Pro-Pol polyprotein from the highly related Jaagsiekte sheep retrovirus (JSRV) suggesting that the polyprotein cleavage sites in the ENTV-1 molecular clone were functional. Mutagenesis of the molecular clone to correct amino acid variants identified within the pro gene did not restore proteolytic processing; whereas deletion of one proline residue from a polyproline tract located in variable region 1 (VR1) of the matrix resulted in production of CA protein of the mature (cleaved) size strongly suggesting that normal virion morphogenesis and polyprotein cleavage took place. Finally, electron microscopy revealed the presence of spherical virus particles with an eccentric capsid and an average diameter of about 100 nm. In summary, we have constructed the first molecular clone of ENTV-1 from which mature virus particles can be produced. Future experiments using virus produced from this molecular clone can now be conducted to fulfill Koch's postulates and demonstrate that ENTV-1 is necessary and sufficient to induce ENA in sheep.

  15. The requirement for freshly isolated human colorectal cancer (CRC) cells in isolating CRC stem cells.

    Science.gov (United States)

    Fan, F; Bellister, S; Lu, J; Ye, X; Boulbes, D R; Tozzi, F; Sceusi, E; Kopetz, S; Tian, F; Xia, L; Zhou, Y; Bhattacharya, R; Ellis, L M

    2015-02-03

    Isolation of colorectal cancer (CRC) cell populations enriched for cancer stem cells (CSCs) may facilitate target identification. There is no consensus regarding the best methods for isolating CRC stem cells (CRC-SCs). We determined the suitability of various cellular models and various stem cell markers for the isolation of CRC-SCs. Established human CRC cell lines, established CRC cell lines passaged through mice, patient-derived xenograft (PDX)-derived cells, early passage/newly established cell lines, and cells directly from clinical specimens were studied. Cells were FAC-sorted for the CRC-SC markers CD44, CD133, and aldehyde dehydrogenase (ALDH). Sphere formation and in vivo tumorigenicity studies were used to validate CRC-SC enrichment. None of the markers studied in established cell lines, grown either in vitro or in vivo, consistently enriched for CRC-SCs. In the three other cellular models, CD44 and CD133 did not reliably enrich for stemness. In contrast, freshly isolated PDX-derived cells or early passage/newly established CRC cell lines with high ALDH activity formed spheres in vitro and enhanced tumorigenicity in vivo, whereas cells with low ALDH activity did not. PDX-derived cells, early passages/newly established CRC cell lines and cells from clinical specimen with high ALDH activity can be used to identify CRC-SC-enriched populations. Established CRC cell lines should not be used to isolate CSCs.

  16. Development to term of cloned cattle derived from donor cells treated with valproic acid.

    Directory of Open Access Journals (Sweden)

    Juliano Rodrigues Sangalli

    Full Text Available Cloning of mammals by somatic cell nuclear transfer (SCNT is still plagued by low efficiency. The epigenetic modifications established during cellular differentiation are a major factor determining this low efficiency as they act as epigenetic barriers restricting reprogramming of somatic nuclei. In this regard, most factors that promote chromatin decondensation, including histone deacetylase inhibitors (HDACis, have been found to increase nuclear reprogramming efficiency, making their use common to improve SCNT rates. Herein we used valproic acid (VPA in SCNT to test whether the treatment of nuclear donor cells with this HDACi improves pre- and post-implantation development of cloned cattle. We found that the treatment of fibroblasts with VPA increased histone acetylation without affecting DNA methylation. Moreover, the treatment with VPA resulted in increased expression of IGF2R and PPARGC1A, but not of POU5F1. However, when treated cells were used as nuclear donors no difference of histone acetylation was found after oocyte reconstruction compared to the use of untreated cells. Moreover, shortly after artificial activation the histone acetylation levels were decreased in the embryos produced with VPA-treated cells. With respect to developmental rates, the use of treated cells as donors resulted in no difference during pre- and post-implantation development. In total, five clones developed to term; three produced with untreated cells and two with VPA-treated cells. Among the calves from treated group, one stillborn calf was delivered at day 270 of gestation whereas the other one was delivered at term but died shortly after birth. Among the calves from the control group, one died seven days after birth whereas the other two are still alive and healthy. Altogether, these results show that in spite of the alterations in fibroblasts resulting from the treatment with VPA, their use as donor cells in SCNT did not improve pre- and post

  17. Isolation and partial characterization of Brazilian samples of feline immunodeficiency virus.

    Science.gov (United States)

    Teixeira, B M; Logan, N; Samman, A; Miyashiro, S I; Brandão, P E; Willett, B J; Hosie, M J; Hagiwara, M K

    2011-09-01

    Feline immunodeficiency virus (FIV) causes a slow progressive degeneration of the immune system which eventually leads to a disease comparable to acquired immune deficiency syndrome (AIDS) in humans. FIV has extensive sequence variation, a typical feature of lentiviruses. Sequence analysis showed that diversity was not evenly distributed throughout the genome, but was greatest in the envelope gene, env. The virus enters host cells via a sequential interaction, initiated by the envelope glycoprotein (env) binding the primary receptor molecule CD134 and followed by a subsequent interaction with chemokine co-receptor CXCR4. The purpose of this study was to isolate and characterize isolates of FIV from an open shelter in São Paulo, Brazil. The separated PBMC from 11 positive cats were co-cultured with MYA-1 cells. Full-length viral env glycoprotein genes were amplified and determined. Chimeric feline × human CD134 receptors were used to investigate the receptor utilization of 17 clones from Brazilian isolates of FIV. Analyses of the sequence present of molecular clones showed that all clones grouped within subtype B. In contrast to the virulent primary isolate FIV-GL8, expression of the first cysteine-rich domain (CRD1) of feline CD134 in the context of human CD134 was sufficient for optimal receptor function for all Brazilian FIV isolates tested. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. Embryos, Clones, and Stem Cells: A Scientific Primer

    Directory of Open Access Journals (Sweden)

    Kenyon S. Tweedell

    2004-01-01

    Full Text Available This article is intended to give the nonspecialist an insight into the nuances of “clones”, cloning, and stem cells. It distinguishes embryonic and adult stem cells, their normal function in the organism, their origin, and how they are recovered to produce stem cell lines in culture. As background, the fundamental processes of embryo development are reviewed and defined, since the manipulation of stem cell lines into desired specialized cells employs many of the same events. Stem cells are defined and characterized and shown how they function in the intact organism during early development and later during cell regeneration in the adult. The complexity of stem cell recovery and their manipulation into specific cells and tissue is illustrated by reviewing current experimentation on both embryonic and adult stem cells in animals and limited research on human stem cell lines. The current and projected use of stem cells for human diseases and repair, along with the expanding methodology for the recovery of human embryonic stem cells, is described. An assessment on the use of human embryonic stem cells is considered from ethical, legal, religious, and political viewpoints.

  19. Human embryo cloning prohibited in Hong Kong.

    Science.gov (United States)

    Liu, Athena

    2005-12-01

    Since the birth of Dolly (the cloned sheep) in 1997, debates have arisen on the ethical and legal questions of cloning-for-biomedical-research (more commonly termed "therapeutic cloning") and of reproductive cloning using human gametes. Hong Kong enacted the Human Reproductive Technology Ordinance (Cap 561) in 2000. Section 15(1)(e) of this Ordinance prohibits the "replacing of the nucleus of a cell of an embryo with a nucleus taken from any other cell," i.e., nucleus substitution. Section 15(1)(f) prohibits the cloning of any embryo. The scope of the latter, therefore, is arguably the widest, prohibiting all cloning techniques such as cell nucleus replacement, embryo splitting, parthenogenesis, and cloning using stem cell lines. Although the Human Reproductive Technology Ordinance is not yet fully operative, this article examines how these prohibitions may adversely impact on basic research and the vision of the Hong Kong scientific community. It concludes that in light of recent scientific developments, it is time to review if the law offers a coherent set of policies in this area.

  20. Isolation and characterization of conditionally immortalized mouse glomerular endothelial cell lines.

    Science.gov (United States)

    Rops, Angelique L; van der Vlag, Johan; Jacobs, Cor W; Dijkman, Henry B; Lensen, Joost F; Wijnhoven, Tessa J; van den Heuvel, Lambert P; van Kuppevelt, Toin H; Berden, Jo H

    2004-12-01

    The culture and establishment of glomerular cell lines has proven to be an important tool for the understanding of glomerular cell functions in glomerular physiology and pathology. Especially, the recent establishment of a conditionally immortalized visceral epithelial cell line has greatly boosted the research on podocyte biology. Glomeruli were isolated from H-2Kb-tsA58 transgenic mice that contain a gene encoding a temperature-sensitive variant of the SV40 large tumor antigen, facilitating proliferative growth at 33 degrees C and differentiation at 37 degrees C. Glomerular endothelial cells were isolated from glomerular outgrowth by magnetic beads loaded with CD31, CD105, GSL I-B4, and ULEX. Clonal cell lines were characterized by immunofluorescence staining with antibodies/lectins specific for markers of endothelial cells, podocytes, and mesangial cells. Putative glomerular endothelial cell lines were analyzed for (1) cytokine-induced expression of adhesion molecules; (2) tube formation on Matrigel coating; and (3) the presence of fenestrae. As judged by immunostaining for Wilms tumor-1, smooth muscle actin (SMA), podocalyxin, and von Willebrand factor (vWF), we obtained putative endothelial, podocyte and mesangial cell lines. The mouse glomerular endothelial cell clone #1 (mGEnC-1) was positive for vWF, podocalyxin, CD31, CD105, VE-cadherin, GSL I-B4, and ULEX, internalized acetylated-low-density lipoprotein (LDL), and showed increased expression of adhesion molecules after activation with proinflammatory cytokines. Furthermore, mGEnC-1 formed tubes and contained nondiaphragmed fenestrae. The mGEnC-1 represents a conditionally immortalized cell line with various characteristics of differentiated glomerular endothelial cells when cultured at 37 degrees C. Most important, mGEnC-1 contains nondiaphragmed fenestrae, which is a unique feature of glomerular endothelial cells.

  1. Intraclonal genome diversity of Pseudomonas aeruginosa clones CHA and TB

    Science.gov (United States)

    2013-01-01

    Background Adaptation of Pseudomonas aeruginosa to different living conditions is accompanied by microevolution resulting in genomic diversity between strains of the same clonal lineage. In order to detect the impact of colonized habitats on P. aeruginosa microevolution we determined the genomic diversity between the highly virulent cystic fibrosis (CF) isolate CHA and two temporally and geographically unrelated clonal variants. The outcome was compared with the intraclonal genome diversity between three more closely related isolates of another clonal complex. Results The three clone CHA isolates differed in their core genome in several dozen strain specific nucleotide exchanges and small deletions from each other. Loss of function mutations and non-conservative amino acid replacements affected several habitat- and lifestyle-associated traits, for example, the key regulator GacS of the switch between acute and chronic disease phenotypes was disrupted in strain CHA. Intraclonal genome diversity manifested in an individual composition of the respective accessory genome whereby the highest number of accessory DNA elements was observed for isolate PT22 from a polluted aquatic habitat. Little intraclonal diversity was observed between three spatiotemporally related outbreak isolates of clone TB. Although phenotypically different, only a few individual SNPs and deletions were detected in the clone TB isolates. Their accessory genome mainly differed in prophage-like DNA elements taken up by one of the strains. Conclusions The higher geographical and temporal distance of the clone CHA isolates was associated with an increased intraclonal genome diversity compared to the more closely related clone TB isolates derived from a common source demonstrating the impact of habitat adaptation on the microevolution of P. aeruginosa. However, even short-term habitat differentiation can cause major phenotypic diversification driven by single genomic variation events and uptake of phage

  2. [Analysis on clone in vitro and tumorigenic capacity in vivo of different subsets cells from the MCF-7 human breast cancer cell line].

    Science.gov (United States)

    Li, Zhi; Liu, Chun-ping; He, Yan-li; Tian, Yuan; Huang, Tao

    2008-07-01

    To investigate whether there are cancer stem cells in the MCF-7 human breast cancer cell line. Flow cytometry was applied to separate different subpopulation cells from MCF-7 cells, and their ability of clone in vitro and reconstruction tumor in vivo were determined. The ability of clone in vitro and reconstruction tumor in vivo were observed in some MCF-7 cells. Contrast with CD44+ CD24+ cells, the proportion of tumorigenic cancer cells in CD44+ CD24- cells is higher. Breast cancer stem cell exists in MCF-7 and it mainly locates the subpopulation of CD44+ CD24- cells, CD44+ CD24+ cell possibly is breast cancer progenitor cell.

  3. [SPREADING OF NCTC CLONE 929 CELLS AFTER RESEEDING].

    Science.gov (United States)

    Petrov, Yu P; Negulyaev, Yu A; Tsupkina, N V

    2015-01-01

    The period (1 h after reseeding) of behaviour of mouse NCTC clone 929 cells to the conditions of artificial cultivation was studied. The time-lapse imaging followed the processing of the cells with ImageJ program was applied. To characterize the parametres cell status we used the cell area (projection of the cell on substrate) and Rp/Ra ratio introduced earlier as a spreading coefficient (Kuz'minykh, Petrov, 2004). After attaching a substratum, cells have a form of sphere (the phase "sphere") as the daughter cells after a mitosis. We revealed however that after this phase the reseeded cells do not start usual spreading and migration along substratum. They pass a phase of equally spreading in all directions and shaping their area as a circle (phase "circle"). This phase is absent of the daughter cells spreading after mitosis. We assume that the phase "circle" is a result of adaptation of the cells to reseedings at artificial cultivation. It is necessary for formation of a substrate composed of own extracellular matrix components (ECM) of the cells. Own ECM facilitates transition of the cells to their usual spreading and migration along substratum.

  4. DNA from radiation resistant human tumor cells transfers resistance to NIH/3T3 cells with varying degrees of penetrance

    International Nuclear Information System (INIS)

    Kasid, U.; Dritschilo, A.; Weichselbaum, R.

    1987-01-01

    Experimental evidence suggests that clinical radiation resistance may correlate with in vitro radiation survival parameters. Specifically, they isolated several cell lines from radioresistant head and neck carcinomas with D/sub 0/ values greater than 2 Gy. The authors co-transfected DNA from cell line SQ2OB (D/sub 0/ = 2.4 Gy) with the rhoSVNeO plasmid into NIH/3T3 cells (D/sub 0/ = 1.7 Gy). Antibiotic G418 resistant, transformed clones were isolated and confirmed by Southern blotting to contain human alu, as well as rhoSVNeO sequences. Screening for radiation resistance with 8Gy (Cs-137) revealed that 3 of 4 tested hybrid clones show a radiation survival intermediate between NIH/3T3 and SQ2OB. This suggests that radiation resistance is a dominant, transfectable phenotype of mammalian cells and can be expressed in more sensitive cells. Karyotyping of resistant hybrid clones shows the presence of double minute chromosomes. Secondary transfection results and experiments to clone the genetic factors responsible for radiation resistance are in progress and results will be reported

  5. Isolation of UV-sensitive mutants of mouse L5178Y cells by a cell suspension spotting method

    International Nuclear Information System (INIS)

    Shiomi, T.; Hieda-Shiomi, N.; Sato, K.

    1982-01-01

    We have isolated 56 UV-sensitive mutant clones from a mouse L51 T/t line of L5178Y cells by a cell suspension spotting method. Five mutants have also been isolated from L51 T/t and L5178Y cells by the method reported by Thompson and coworkers. We divided the mutants into two groups, highly sensitive and moderately sensitive mutants, according to their sensitivity to UV irradiation. Fifty-eight mutants were highly sensitive and three were moderately sensitive to UV. The reconstruction experiments indicate that more than 90% of highly sensitive mutants were recovered by the cell suspension spotting method. Frequencies of recovered mutants highly sensitive to UV increased with increasing dose of mutagens. Recovered mutant frequency reached 10(-2) after treatment with 1.5 micrograms/ml of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) (survival 0.2%). Eight UV-sensitive mutants were divided into four complementation groups. These mutants were 2-6 times more sensitive to UV than parental L51 T/t cells in terms of D37 (dose required to reduce survival to 37%). Four representative UV-sensitive mutants which are classified into different complementation groups were examined for their sensitivity to killing by UV, 4-nitroquinoline-1-oxide (4NQO), mitomycin C (MMC), X-rays, and MNNG. All four classes of mutants were found to be cross-sensitive to UV, 4NQO, and MMC, but not sensitive to X-rays and MNNG

  6. [Cloning and characterization of genes differentially expressed in human dental pulp cells and gingival fibroblasts].

    Science.gov (United States)

    Wang, Zhong-dong; Wu, Ji-nan; Zhou, Lin; Ling, Jun-qi; Guo, Xi-min; Xiao, Ming-zhen; Zhu, Feng; Pu, Qin; Chai, Yu-bo; Zhao, Zhong-liang

    2007-02-01

    To study the biological properties of human dental pulp cells (HDPC) by cloning and analysis of genes differentially expressed in HDPC in comparison with human gingival fibroblasts (HGF). HDPC and HGF were cultured and identified by immunocytochemistry. HPDC and HGF subtractive cDNA library was established by PCR-based modified subtractive hybridization, genes differentially expressed by HPDC were cloned, sequenced and compared to find homogeneous sequence in GenBank by BLAST. Cloning and sequencing analysis indicate 12 genes differentially expressed were obtained, in which two were unknown genes. Among the 10 known genes, 4 were related to signal transduction, 2 were related to trans-membrane transportation (both cell membrane and nuclear membrane), and 2 were related to RNA splicing mechanisms. The biological properties of HPDC are determined by the differential expression of some genes and the growth and differentiation of HPDC are associated to the dynamic protein synthesis and secretion activities of the cell.

  7. Inhibition of clone formation as an assay for T cell-mediated cytotoxicity: short-term kinetics and comparison with 51Cr release

    International Nuclear Information System (INIS)

    Lees, R.K.; MacDonald, H.R.; Sinclair, N.R.; University of Western Ontario London

    1977-01-01

    The short-term kinetics of T cell-mediated cytotoxicity was investigated using a cloning inhibition assay. Murine cytotoxic thymus-derived lymphocytes generated in vitro in mixed leukocyte cultures were incubated for various periods of time at 37degC with allogeneic mastocytoma target cells. The mixtures were then plated in soft agar, and mastocytoma clone formation was assessed after 5-7 days incubation. Using this technique, it was demonstrated that events leading to the loss of cloning ability could be detected after 1-3 min incubation at 37degC, and after 20-30 min, 95% of the clone forming cells had been inactivated. When these results were compared directly with those obtained using the conventional 51 Cr-release assay, it was found that the events leading to loss of cloning ability occurred more rapidly than indicated by the isotope assay. However, a modification of the 51 Cr-release assay involving EDTA addition gave comparable result to the cloning inhibition assay. These results raise the possibility that the events leading to 51 Cr-release of tumor target cells may be related in time to those leading to the loss of cloning ability

  8. Molecular cloning of the α subunit of human and guinea pig leukocyte adhesion glycoprotein Mo1: Chromosomal localization and homology to the α subunits of integrins

    International Nuclear Information System (INIS)

    Arnaout, M.A.; Remold-O'Donnell, E.; Pierce, M.W.; Harris, P.; Tenen, D.G.

    1988-01-01

    The cell surface-glycoprotein Mo1 is a member of the family of leukocyte cell adhesion molecules (Leu-CAMs) that includes lymphocyte function-associated antigen 1 (LFA-1) and p150,95. Each Leu-CAM is a heterodimer with a distinct α subunit noncovalently associated with a common β subunit. The authors describe the isolation and analysis of two partial cDNA clones encoding the α subunit of the Leu-CAM Mo1 in humans and guinea pigs. A monoclonal antibody directed against an epitope in the carboxyl-terminal portion of the guinea pig α chain was used for immunoscreening a λgt11 expression library. The sequence of a 378-base-pair insert from one immunoreactive clone revealed a single continuous open reading frame encoding 126 amino acids including a 26-amino acid tryptic peptide isolated from the purified guinea pig α subunit. A cDNA clone of identical size was isolated from a human monocyte/lymphocyte cDNA library by using the guinea pig clone as a probe. The human clone also encoded a 126-amino acid peptide including the sequence of an additional tryptic peptide present in purified human Mo1α chain. Southern analysis of DNA from hamster-human hybrids localized the human Mo1α chain to chromosome 16, which has been shown to contain the gene for the α chain of lymphocyte function-associated antigen 1. These data suggest that the α subunits of Leu-CAMs evolved by gene duplication from a common ancestral gene and strengthen the hypothesis that the α subunits of these heterodimeric cell adhesion molecules on myeloid and lymphoid cells, platelets, and fibroblasts are evolutionary related

  9. Species-specific challenges in dog cloning.

    Science.gov (United States)

    Kim, G A; Oh, H J; Park, J E; Kim, M J; Park, E J; Jo, Y K; Jang, G; Kim, M K; Kim, H J; Lee, B C

    2012-12-01

    Somatic cell nuclear transfer (SCNT) is now an established procedure used in cloning of several species. SCNT in dogs involves multiple steps including the removal of the nuclear material, injection of a donor cell, fusion, activation of the reconstructed oocytes and finally transfer to a synchronized female recipient. There are therefore many factors that contribute to cloning efficiency. By performing a retrospective analysis of 2005-2012 published papers regarding dog cloning, we define the optimum procedure and summarize the specific feature for dog cloning. © 2012 Blackwell Verlag GmbH.

  10. Long-term effect on in vitro cloning efficiency after treatment of somatic cells with Xenopus egg extract in the pig.

    Science.gov (United States)

    Liu, Ying; Ostrup, Olga; Li, Rong; Li, Juan; Vajta, Gábor; Kragh, Peter M; Schmidt, Mette; Purup, Stig; Hyttel, Poul; Klærke, Dan; Callesen, Henrik

    2014-08-01

    In somatic cell nuclear transfer (SCNT), donor cell reprogramming is considered as a biologically important and vulnerable event. Various donor cell pre-treatments with Xenopus egg extracts can promote reprogramming. Here we investigated if the reprogramming effect of one treatment with Xenopus egg extract on donor cells was maintained for several cell passages. The extract treatment resulted in increased cell-colony formation from early passages in treated porcine fibroblasts (ExTES), and increased development of cloned embryos. Partial dedifferentiation was observed in ExTES cells, shown as a tendency towards upregulation of NANOG, c-MYC and KLF-4 and downregulation of DESMIM compared with ExTES at Passage 2. Compared with our routine SCNT, continuously increased development of cloned embryos was observed in the ExTES group, and ExTES cloned blastocysts displayed hypermethylated DNA patterns and hypermethylation of H3K4me3 and H3K27me3 in ICM compared with TE. All seven recipients became pregnant after transferral of ExTES cloned embryos and gave birth to 7-22 piglets per litter (average 12). In conclusion, our results demonstrate that one treatment of porcine fibroblasts with Xenopus egg extract can result in long-term increased ability of the cells to promote their in vitro function in subsequent SCNT. Finally these cells can also result in successful development of cloned embryos to term.

  11. Effective donor cell fusion conditions for production of cloned dogs by somatic cell nuclear transfer.

    Science.gov (United States)

    Park, JungEun; Oh, HyunJu; Hong, SoGun; Kim, MinJung; Kim, GeonA; Koo, OkJae; Kang, SungKeun; Jang, Goo; Lee, ByeongChun

    2011-03-01

    As shown by the birth of the first cloned dog 'Snuppy', a protocol to produce viable cloned dogs has been reported. In order to evaluate optimum fusion conditions for improving dog cloning efficiency, in vivo matured oocytes were reconstructed with adult somatic cells from a female Pekingese using different fusion conditions. Fusion with needle vs chamber methods, and with low vs high pulse strength was compared by evaluating fusion rate and in vivo development of canine cloned embryos. The fusion rates in the high voltage groups were significantly higher than in the low voltage groups regardless of fusion method (83.5 vs 66.1% for the needle fusion method, 67.4 vs 37.9% for the fusion chamber method). After embryo transfer, one each pregnancy was detected after using the needle fusion method with high and low voltage and in the chamber fusion method with high voltage, whereas no pregnancy was detected using the chamber method with low voltage. However, only the pregnancy from the needle fusion method with high voltage was maintained to term and one healthy puppy was delivered. The results of the present study demonstrated that two DC pulses of 3.8 to 4.0 kV/cm for 15 μsec using the needle fusion method were the most effective method for the production of cloned dogs under the conditions of this experiment. Copyright © 2011 Elsevier Inc. All rights reserved.

  12. A versatile system for USER cloning-based assembly of expression vectors for mammalian cell engineering.

    Directory of Open Access Journals (Sweden)

    Anne Mathilde Lund

    Full Text Available A new versatile mammalian vector system for protein production, cell biology analyses, and cell factory engineering was developed. The vector system applies the ligation-free uracil-excision based technique--USER cloning--to rapidly construct mammalian expression vectors of multiple DNA fragments and with maximum flexibility, both for choice of vector backbone and cargo. The vector system includes a set of basic vectors and a toolbox containing a multitude of DNA building blocks including promoters, terminators, selectable marker- and reporter genes, and sequences encoding an internal ribosome entry site, cellular localization signals and epitope- and purification tags. Building blocks in the toolbox can be easily combined as they contain defined and tested Flexible Assembly Sequence Tags, FASTs. USER cloning with FASTs allows rapid swaps of gene, promoter or selection marker in existing plasmids and simple construction of vectors encoding proteins, which are fused to fluorescence-, purification-, localization-, or epitope tags. The mammalian expression vector assembly platform currently allows for the assembly of up to seven fragments in a single cloning step with correct directionality and with a cloning efficiency above 90%. The functionality of basic vectors for FAST assembly was tested and validated by transient expression of fluorescent model proteins in CHO, U-2-OS and HEK293 cell lines. In this test, we included many of the most common vector elements for heterologous gene expression in mammalian cells, in addition the system is fully extendable by other users. The vector system is designed to facilitate high-throughput genome-scale studies of mammalian cells, such as the newly sequenced CHO cell lines, through the ability to rapidly generate high-fidelity assembly of customizable gene expression vectors.

  13. Cloning and Expression of Luteinizing Hormone Subunits in Chinese Hamster Ovary Cell Line

    Directory of Open Access Journals (Sweden)

    Zeinab Soleimanifar

    2016-10-01

    Full Text Available Background: Luteinizing hormone (LH was secreted by the stimulating cells of the testes and ovaries in the anterior pituitary gland. The application of this hormone is in the treatment of men and women with infertility and amenorrhea respectively.Materials and Methods: In the present study the alpha and beta subunits of human LH gene were cloned into the pEGFP-N1 expression vector and produced the recombinant LH hormone in Chinese hamster ovary (CHO eukaryotic system.Results: Alpha and beta subunits of LH hormone were cloned between NheI and BamHI cut sites of pEGFP_N1 expression plasmid and confirmed by PCR.  Hormone expression was evaluated in CHO cell line by Western blotting using the specific antibody.Conclusion: Alpha and beta subunits of LH hormone were expressed in CHO cell line perfectly.

  14. Efficient production of a gene mutant cell line through integrating TALENs and high-throughput cell cloning.

    Science.gov (United States)

    Sun, Changhong; Fan, Yu; Li, Juan; Wang, Gancheng; Zhang, Hanshuo; Xi, Jianzhong Jeff

    2015-02-01

    Transcription activator-like effectors (TALEs) are becoming powerful DNA-targeting tools in a variety of mammalian cells and model organisms. However, generating a stable cell line with specific gene mutations in a simple and rapid manner remains a challenging task. Here, we report a new method to efficiently produce monoclonal cells using integrated TALE nuclease technology and a series of high-throughput cell cloning approaches. Following this method, we obtained three mTOR mutant 293T cell lines within 2 months, which included one homozygous mutant line. © 2014 Society for Laboratory Automation and Screening.

  15. [Mystery and problems of cloning].

    Science.gov (United States)

    Nikitin, V A

    2010-01-01

    The attention of investigators is attracted to the fact that, in spite of great efforts in mammalian cloning, advances that have been made in this area of research are not great, and cloned animals have developmental pathologies often incompatible with life and/or reproduction ability. It is yet not clear what technical or biological factors underlie this, and how they are connected or interact with each other, which is more realistic strategically. There is a great number of articles dealing with the influence of cloning with the nuclear transfer on genetic and epigenetic reprogramming of donor cells. At the same time we can see the practical absence of analytical investigations concerning the technology of cloning as such, its weak points, and possible sources of cellular trauma in the course of microsurgery of nuclear transfer or twinning. This article discusses step by step several nuclear transfer techniques and the methods of dividing early preimplanted embryos for twinning with the aim to reveal possible sources of cell damage during micromanipulation that may have negative influence on the development of cloned organisms. Several new author's technologies based on the study of cell biophysical characteristics are described, which allow one to avoid cellular trauma during manipulation and minimize the possibility of cell damage at any rate.

  16. Different Donor Cell Culture Methods Can Influence the Developmental Ability of Cloned Sheep Embryos.

    Directory of Open Access Journals (Sweden)

    LiBing Ma

    Full Text Available It was proposed that arresting nuclear donor cells in G0/G1 phase facilitates the development of embryos that are derived from somatic cell nuclear transfer (SCNT. Full confluency or serum starvation is commonly used to arrest in vitro cultured somatic cells in G0/G1 phase. However, it is controversial as to whether these two methods have the same efficiency in arresting somatic cells in G0/G1 phase. Moreover, it is unclear whether the cloned embryos have comparable developmental ability after somatic cells are subjected to one of these methods and then used as nuclear donors in SCNT. In the present study, in vitro cultured sheep skin fibroblasts were divided into four groups: (1 cultured to 70-80% confluency (control group, (2 cultured to full confluency, (3 starved in low serum medium for 4 d, or (4 cultured to full confluency and then further starved for 4 d. Flow cytometry was used to assay the percentage of fibroblasts in G0/G1 phase, and cell counting was used to assay the viability of the fibroblasts. Then, real-time reverse transcription PCR was used to determine the levels of expression of several cell cycle-related genes. Subsequently, the four groups of fibroblasts were separately used as nuclear donors in SCNT, and the developmental ability and the quality of the cloned embryos were compared. The results showed that the percentage of fibroblasts in G0/G1 phase, the viability of fibroblasts, and the expression levels of cell cycle-related genes was different among the four groups of fibroblasts. Moreover, the quality of the cloned embryos was comparable after these four groups of fibroblasts were separately used as nuclear donors in SCNT. However, cloned embryos derived from fibroblasts that were cultured to full confluency combined with serum starvation had the highest developmental ability. The results of the present study indicate that there are synergistic effects of full confluency and serum starvation on arresting fibroblasts in

  17. Immune-mediated bone marrow failure syndromes of progenitor and stem cells: molecular analysis of cytotoxic T cell clones.

    Directory of Open Access Journals (Sweden)

    Ramon Tiu

    2007-03-01

    Full Text Available The unique structure of the T cell receptor (TCR enables molecular identification of individual T cell clones and provides an unique opportunity for the design of molecular diagnostic tests based on the structure of the rearranged TCR chain e.g., using the TCR CDR3 region. Initially, clonal T cell malignancies, including T cell large granular lymphocyte leukemia (T-LGL, mucosis fungoides and peripheral T cell lymphoma were targets for the TCR-based analytic assays such as detection of clonality by T-gamma rearrangement using y-chain-specific PCR or Southern Blotting. Study of these disorders facilitated further analytic concepts and application of rational methods of TCR analysis to investigations of polyclonal T cell-mediated diseases. In hematology, such conditions include graft versus host disease (GvHD and immune-mediated bone marrow failure syndromes. In aplastic anemia (AA, myelodysplastic syndrome (MDS or paroxysmal nocturnal hemoglobinuria (PNH, cytotoxic T cell responses may be directed against certain antigens located on stem or more lineage-restricted progenitor cells in single lineage cytopenias. The nature of the antigenic targets driving polyclonal CTL responses remains unclear. Novel methods of TCR repertoire analysis, include VB flow cytometry, peptide-specific tetramer staining, in vitro stimulation assays and TCR CDR3-specific PCR. Such PCR assay can be either VB family-specific or multiplexed for all VB families. Amplified products can be characterized and quantitated to facilitate detection of the most immunodominant clonotypes. Such clonotypes may serve as markers for the global polyclonal T cell response. Identification of these clonotypes can be performed in blood and tissue biopsy material by various methods. Once immunodominant clonotypes corresponding to pathogenic CTL clones are identified they can serve as surrogate markers for the activity of the pathophysiologic process or even indicate the presence of specific

  18. Antigen-specific murine T cell clones produce soluble interleukin 2 receptor on stimulation with specific antigens

    International Nuclear Information System (INIS)

    Wagner, D.K.; York-Jolley, J.; Malek, T.R.; Berzofsky, J.A.; Nelson, D.L.

    1986-01-01

    In this study, monoclonal antibodies were used to the murine IL 2 receptor (IL 2R) termed 3C7 and 7D4, which bind to different epitopes on the murine IL 2R, to develop an ELISA to measure soluble murine IL 2R. Surprisingly, stimulated murine spleen cells not only expressed cell-associated IL 2R, but also produced a considerable level of cellfree IL 2R in the culture supernatant fluid. To assess the fine specificity of this response, myoglobin-immune murine T cell clones were stimulated with appropriate or inappropriate antigen and syngeneic or allogeneic presenting cells. Proliferation, measured by [ 3 H] thymidine incorporation, and levels of soluble IL 2R were determined at day 4. The production of soluble IL2R displayed the same epitope fine specificity, genetic restriction, and antigen dose-response as the proliferative response. Indeed, in some cases there was sharper discrimination of epitope specificity and genetic restriction with the soluble IL 2R levels. There was also reproducible clone-to-clone variation in the amount of soluble receptor produced in response to antigen among 12 T cell clones and lines tested. In time course experiments, proliferation was greatest at day 3, whereas soluble IL 2R levels continued to rise in subsequent days. To the authors' knowledge, this is the first demonstration of release of secretion of soluble IL 2R by murine T cells, and the first demonstration of the fine specificity and genetic restriction of the induction of soluble IL 2R by specific antigen

  19. T cell epitopes on the 36K and 65K Mycobacterium leprae antigens defined by human T cell clones

    NARCIS (Netherlands)

    van Schooten, W. C.; Ottenhoff, T. H.; Klatser, P. R.; Thole, J.; de Vries, R. R.; Kolk, A. H.

    1988-01-01

    To identify the molecular localization and specificity of Mycobacterium leprae antigenic determinants inducing T cell activation, we studied the reactivity of M. leprae-reactive T cell clones from two tuberculoid leprosy patients towards a battery of different mycobacterial strains and purified

  20. MAdCAM-1 is needed for diabetes development mediated by the T cell clone, BDC-2·5

    Science.gov (United States)

    Phillips, Jenny M; Haskins, Kathryn; Cooke, Anne

    2005-01-01

    The NOD-derived islet-reactive CD4+ T cell clone, BDC-2·5, is able to transfer diabetes to neonatal non-obese diabetic (NOD) mice but is unable to transfer disease to either adult NOD or NOD scid recipients. Transfer of diabetes to adult recipients by BDC-2·5 is only accomplished by cotransfer of CD8+ T cells from a diabetic donor. To understand why this CD4+ T cell clone is able to mediate diabetes in neonatal but not the adult recipients we examined the ability of the clone to traffic in the different recipients. Our studies showed that MAdCAM-1 has a very different expression pattern in the neonatal and adult pancreas. Blockade of this addressin prevents the clone from transferring diabetes to neonatal mice, suggesting that the differential pancreatic expression of MAdCAM-1 in neonatal and adult pancreas provides an explanation of the differences in diabetes development. PMID:16313366

  1. Mutation induction and isolation in potato through true seed and tuber mutagenesis and use of tissue culture

    International Nuclear Information System (INIS)

    Upadhya, M.D.; Abraham, M.J.; Dass, B.; Chandra, R.

    1982-01-01

    Advance MV generation clones from hydrazine-sulphate-treated 'O.T' cultures have been field evaluated and 12 cultures have been selected for yield trials. One culture, DN-31-3, has been found to be day-neutral in its tuberization behaviour. Four JL/RA clones have been selected after a large-scale field trial. These clones are the selections from gamma-irradiated self seeds of Kufri Lauvkar (A-7416) and hybrid A-2235. Similarly 15 MV 3 clones have been selected from the populations raised from EMS- and DES-treated self seeds of A-2235. Day-neutral mutants have been selected from the fourth to seventh sprouts taken from EMS-treated tuber halves of Kufri Jyoti. From the sixth sprout harvest from EMS-treated Kufri Jyoti halves, one mutant, BCN-6-2, has been isolated which showed less than 30 cysts of G. rostochiensis in the MV 2 generation. This clone has been multiplied and made disease-free through apical meristem culture. Through the use of a new medium, PM-32, the plating efficiency of mechanically isolated single callus cells of dihaploid PH-258 is 30-35%. Nitsch's medium has been modified to formulate a new medium for direct embryogenesis in single callus cells of Phulwa. All stages up to the globular stage could be observed after five to six weeks of culture. Efforts were continued for the enzymatic isolation of single-leaf mesophyll cells from dihaploid PH-258. A new cell separation medium has been formulated which gives 80% viable cells. The LD 50 and LD 100 doses of EMS for the single callus cells of dihaploid PH-255 were found to be 500 ppm and 1000 ppm respectively. (author)

  2. Chorioallantoic placenta defects in cloned mice

    International Nuclear Information System (INIS)

    Wakisaka-Saito, Noriko; Kohda, Takashi; Inoue, Kimiko; Ogonuki, Narumi; Miki, Hiromi; Hikichi, Takafusa; Mizutani, Eiji; Wakayama, Teruhiko; Kaneko-Ishino, Tomoko; Ogura, Atsuo; Ishino, Fumitoshi

    2006-01-01

    Somatic cell nuclear transfer technology has been applied to produce live clones successfully in several mammalian species, but the success rates are very low. In mice, about half of the nuclear transfer embryos undergo implantation, but very few survive to term. We undertook detailed histological analyses of placentas from cloned mouse embryos generated from cumulus cells at 10.5 dpc of pregnancy, by which stage most clones have terminated their development. At 10.5 dpc, the extraembryonic tissues displayed several defined histological patterns, each reflecting their stage of developmental arrest. The most notable abnormality was the poor development of the spongiotrophoblast layer of diploid cells. This is in contrast to the placental hyperplasia frequently observed in somatic clones at 12.5 dpc or later stages. A variety of structural abnormalities were also observed in the embryos. Both placental and embryonic defects likely contribute to the low success rate of the mouse clones

  3. [Scientific ethics of human cloning].

    Science.gov (United States)

    Valenzuela, Carlos Y

    2005-01-01

    True cloning is fission, budding or other types of asexual reproduction. In humans it occurs in monozygote twinning. This type of cloning is ethically and religiously good. Human cloning can be performed by twinning (TWClo) or nuclear transfer (NTClo). Both methods need a zygote or a nuclear transferred cell, obtained in vitro (IVTec). They are under the IVTec ethics. IVTecs use humans (zygotes, embryos) as drugs or things; increase the risk of malformations; increase development and size of abnormalities and may cause long-term changes. Cloning for preserving extinct (or almost extinct) animals or humans when sexual reproduction is not possible is ethically valid. The previous selection of a phenotype in human cloning violates some ethical principles. NTClo for reproductive or therapeutic purposes is dangerous since it increases the risk for nucleotide or chromosome mutations, de-programming or re-programming errors, aging or malignancy of the embryo cells thus obtained.

  4. [Cloning of Clostridium perfringens alpha-toxin gene and extracellular expression in Escherichia coli].

    Science.gov (United States)

    Inoue, Masaharu; Kikuchi, Maho; Komoriya, Tomoe; Watanabe, Kunitomo; Kouno, Hideki

    2007-01-01

    Clostridium perfringens (C. perfringens) is a Gram-positive bacterial pathogen that widely propagets in the soil and the gastrointestinal tract of human and animals. This bacteria causes food poisoning, gas gangrene and other various range of infectious diseases. But there is no standard diagnosis method of C. perfringens. In order to develop a new type of immunoassay for clinical purpose, we studied expression and extracellular secretion of recombinant alpha-toxin having enzyme activity in E. coli expression system. Cloning was carried out after PCR amplification from C. perfringens GAI 94074 which was clinical isolate. Three kinds of fragment were cloned using pET100/D-TOPO vector. These fragments coded for ribosome binding site, signal peptide, and alpha-toxin gene respectively. Recombinant pET100 plasmid transformed into TOP 10 cells and the obtained plasmids were transformed into BL21 (DE3) cells. Then, the transformants were induced expression with IPTG. In conclusion, we successfully cloned, expressed and exteracellular secreted C. perfringens alpha-toxin containing signal peptide. Biologically, the obtained recombinant protein was positive for phospholipase C activity.

  5. Neutralizing Activity of Broadly Neutralizing Anti-HIV-1 Antibodies against Clade B Clinical Isolates Produced in Peripheral Blood Mononuclear Cells.

    Science.gov (United States)

    Cohen, Yehuda Z; Lorenzi, Julio C C; Seaman, Michael S; Nogueira, Lilian; Schoofs, Till; Krassnig, Lisa; Butler, Allison; Millard, Katrina; Fitzsimons, Tomas; Daniell, Xiaoju; Dizon, Juan P; Shimeliovich, Irina; Montefiori, David C; Caskey, Marina; Nussenzweig, Michel C

    2018-03-01

    Recently discovered broadly neutralizing antibodies (bNAbs) against HIV-1 demonstrate extensive breadth and potency against diverse HIV-1 strains and represent a promising approach for the treatment and prevention of HIV-1 infection. The breadth and potency of these antibodies have primarily been evaluated by using panels of HIV-1 Env-pseudotyped viruses produced in 293T cells expressing molecularly cloned Env proteins. Here we report on the ability of five bNAbs currently in clinical development to neutralize circulating primary HIV-1 isolates derived from peripheral blood mononuclear cells (PBMCs) and compare the results to those obtained with the pseudovirus panels used to characterize the bNAbs. The five bNAbs demonstrated significantly less breadth and potency against clinical isolates produced in PBMCs than against Env-pseudotyped viruses. The magnitude of this difference in neutralizing activity varied, depending on the antibody epitope. Glycan-targeting antibodies showed differences of only 3- to 4-fold, while antibody 10E8, which targets the membrane-proximal external region, showed a nearly 100-fold decrease in activity between published Env-pseudotyped virus panels and PBMC-derived primary isolates. Utilizing clonal PBMC-derived primary isolates and molecular clones, we determined that the observed discrepancy in bNAb performance is due to the increased sensitivity to neutralization exhibited by 293T-produced Env-pseudotyped viruses. We also found that while full-length molecularly cloned viruses produced in 293T cells exhibit greater sensitivity to neutralization than PBMC-derived viruses do, Env-pseudotyped viruses produced in 293T cells generally exhibit even greater sensitivity to neutralization. As the clinical development of bNAbs progresses, it will be critical to determine the relevance of each of these in vitro neutralization assays to in vivo antibody performance. IMPORTANCE Novel therapeutic and preventive strategies are needed to contain the

  6. Isolation, molecular cloning and expression of cellobiohydrolase B (CbhB) from Aspergillus niger in Escherichia coli

    International Nuclear Information System (INIS)

    Woon, J. S. K.; Murad, A. M. A.; Abu Bakar, F. D.

    2015-01-01

    A cellobiohydrolase B (CbhB) from Aspergillus niger ATCC 10574 was cloned and expressed in E. coli. CbhB has an open reading frame of 1611 bp encoding a putative polypeptide of 536 amino acids. Analysis of the encoded polypeptide predicted a molecular mass of 56.2 kDa, a cellulose binding module (CBM) and a catalytic module. In order to obtain the mRNA of cbhB, total RNA was extracted from A. niger cells induced by 1% Avicel. First strand cDNA was synthesized from total RNA via reverse transcription. The full length cDNA of cbhB was amplified by PCR and cloned into the cloning vector, pGEM-T Easy. A comparison between genomic DNA and cDNA sequences of cbhB revealed that the gene is intronless. Upon the removal of the signal peptide, the cDNA of cbhB was cloned into the expression vector pET-32b. However, the recombinant CbhB was expressed in Escherichia coli Origami DE3 as an insoluble protein. A homology model of CbhB predicted the presence of nine disulfide bonds in the protein structure which may have contributed to the improper folding of the protein and thus, resulting in inclusion bodies in E. coli

  7. Isolation, molecular cloning and expression of cellobiohydrolase B (CbhB) from Aspergillus niger in Escherichia coli

    Energy Technology Data Exchange (ETDEWEB)

    Woon, J. S. K., E-mail: jameswoon@siswa.ukm.edu.my; Murad, A. M. A., E-mail: munir@ukm.edu.my; Abu Bakar, F. D., E-mail: fabyff@ukm.edu.my [School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor (Malaysia)

    2015-09-25

    A cellobiohydrolase B (CbhB) from Aspergillus niger ATCC 10574 was cloned and expressed in E. coli. CbhB has an open reading frame of 1611 bp encoding a putative polypeptide of 536 amino acids. Analysis of the encoded polypeptide predicted a molecular mass of 56.2 kDa, a cellulose binding module (CBM) and a catalytic module. In order to obtain the mRNA of cbhB, total RNA was extracted from A. niger cells induced by 1% Avicel. First strand cDNA was synthesized from total RNA via reverse transcription. The full length cDNA of cbhB was amplified by PCR and cloned into the cloning vector, pGEM-T Easy. A comparison between genomic DNA and cDNA sequences of cbhB revealed that the gene is intronless. Upon the removal of the signal peptide, the cDNA of cbhB was cloned into the expression vector pET-32b. However, the recombinant CbhB was expressed in Escherichia coli Origami DE3 as an insoluble protein. A homology model of CbhB predicted the presence of nine disulfide bonds in the protein structure which may have contributed to the improper folding of the protein and thus, resulting in inclusion bodies in E. coli.

  8. Isolation, molecular cloning and expression of cellobiohydrolase B (CbhB) from Aspergillus niger in Escherichia coli

    Science.gov (United States)

    Woon, J. S. K.; Murad, A. M. A.; Abu Bakar, F. D.

    2015-09-01

    A cellobiohydrolase B (CbhB) from Aspergillus niger ATCC 10574 was cloned and expressed in E. coli. CbhB has an open reading frame of 1611 bp encoding a putative polypeptide of 536 amino acids. Analysis of the encoded polypeptide predicted a molecular mass of 56.2 kDa, a cellulose binding module (CBM) and a catalytic module. In order to obtain the mRNA of cbhB, total RNA was extracted from A. niger cells induced by 1% Avicel. First strand cDNA was synthesized from total RNA via reverse transcription. The full length cDNA of cbhB was amplified by PCR and cloned into the cloning vector, pGEM-T Easy. A comparison between genomic DNA and cDNA sequences of cbhB revealed that the gene is intronless. Upon the removal of the signal peptide, the cDNA of cbhB was cloned into the expression vector pET-32b. However, the recombinant CbhB was expressed in Escherichia coli Origami DE3 as an insoluble protein. A homology model of CbhB predicted the presence of nine disulfide bonds in the protein structure which may have contributed to the improper folding of the protein and thus, resulting in inclusion bodies in E. coli.

  9. Characterization of a mutant rat kangaroo cell line with alterations in the cell cycle and DNA repair

    Directory of Open Access Journals (Sweden)

    Miyaji E.N.

    2000-01-01

    Full Text Available Using a positive selection system for isolating DNA replication and repair related mutants, we isolated a clone from a rat kangaroo cell line (PtK2 that has increased sensitivity to UV light. Characterization of this clone indicated normal post-replication repair after UV irradiation, and normal removal rates of cyclobutane pyrimidine dimers and pyrimidine(6-4pyrimidone photoproducts by excision repair. However, this cell line has decreased ability to make early incisions on damaged DNA, possibly indicating a defect in preferential repair of actively transcribed genes, and a slower cell proliferation rate, including a longer S-phase. This phenotype reinforces the present notion that control of key mechanisms in cell metabolism, such as cell cycle control, repair, transcription and cell death, can be linked.

  10. Cloning and expression of cDNA coding for bouganin.

    Science.gov (United States)

    den Hartog, Marcel T; Lubelli, Chiara; Boon, Louis; Heerkens, Sijmie; Ortiz Buijsse, Antonio P; de Boer, Mark; Stirpe, Fiorenzo

    2002-03-01

    Bouganin is a ribosome-inactivating protein that recently was isolated from Bougainvillea spectabilis Willd. In this work, the cloning and expression of the cDNA encoding for bouganin is described. From the cDNA, the amino-acid sequence was deduced, which correlated with the primary sequence data obtained by amino-acid sequencing on the native protein. Bouganin is synthesized as a pro-peptide consisting of 305 amino acids, the first 26 of which act as a leader signal while the 29 C-terminal amino acids are cleaved during processing of the molecule. The mature protein consists of 250 amino acids. Using the cDNA sequence encoding the mature protein of 250 amino acids, a recombinant protein was expressed, purified and characterized. The recombinant molecule had similar activity in a cell-free protein synthesis assay and had comparable toxicity on living cells as compared to the isolated native bouganin.

  11. Isolation and Cloning of cDNA Fragment of Gene Encoding for Multidrug Resistance Associated Protein from M. affine.

    Directory of Open Access Journals (Sweden)

    Utut Widyastuti Suharsono

    2008-11-01

    Full Text Available Isolation and Cloning of cDNA Fragment of Gene Encoding for Multidrug Resistance Associated Protein from M. affine. M. affine can grow well in acid soil with high level of soluble aluminum. One of the important proteins in the detoxifying xenobiotic stress including acid and Al stresses is a multidrug resistance associated protein (MRP encoded by mrp gene. The objective of this research is to isolate and clone the cDNA fragment of MaMrp encoding MRP from M. affine. By reverse transcription, total cDNA had been synthesized from the total RNA as template. The fragment of cDNA MaMrp had been successfully isolated by PCR by using total cDNA as template and mrp primer designed from A. thaliana, yeast, and human. This fragment was successfully inserted into pGEM-T Easy and the recombinant plasmid was successfully introduced into E. coli DH5α. Nucleotide sequence analysis showed that the lenght of MaMrp fragment is 633 bp encoding 208 amino acids. Local alignment analysis based on nucleotide of mRNA showed that MaMrp fragment is 69% identical to AtMrp1 and 63% to AtMrp from A. thaliana. Based on deduced amino acid sequence, MaMRP is 84% identical to part of AtMRP13, 77% to AtMRP12, and 73% to AtMRP1 from A. thaliana respectively. Alignment analysis with AtMRP1 showed that MaMRP fragment is located in TM1 and NBF1 domains and has a specific amino acid sequence QCKAQLQNMEEE.

  12. Human cloning: can it be made safe?

    Science.gov (United States)

    Rhind, Susan M; Taylor, Jane E; De Sousa, Paul A; King, Tim J; McGarry, Michelle; Wilmut, Ian

    2003-11-01

    There are continued claims of attempts to clone humans using nuclear transfer, despite the serious problems that have been encountered in cloning other mammals. It is known that epigenetic and genetic mechanisms are involved in clone failure, but we still do not know exactly how. Human reproductive cloning is unethical, but the production of cells from cloned embryos could offer many potential benefits. So, can human cloning be made safe?

  13. Survival of Skin Graft between Transgenic Cloned Dogs and Non-Transgenic Cloned Dogs

    Science.gov (United States)

    Kim, Geon A; Oh, Hyun Ju; Kim, Min Jung; Jo, Young Kwang; Choi, Jin; Park, Jung Eun; Park, Eun Jung; Lim, Sang Hyun; Yoon, Byung Il; Kang, Sung Keun; Jang, Goo; Lee, Byeong Chun

    2014-01-01

    Whereas it has been assumed that genetically modified tissues or cells derived from somatic cell nuclear transfer (SCNT) should be accepted by a host of the same species, their immune compatibility has not been extensively explored. To identify acceptance of SCNT-derived cells or tissues, skin grafts were performed between cloned dogs that were identical except for their mitochondrial DNA (mtDNA) haplotypes and foreign gene. We showed here that differences in mtDNA haplotypes and genetic modification did not elicit immune responses in these dogs: 1) skin tissues from genetically-modified cloned dogs were successfully transplanted into genetically-modified cloned dogs with different mtDNA haplotype under three successive grafts over 63 days; and 2) non-transgenic cloned tissues were accepted into transgenic cloned syngeneic recipients with different mtDNA haplotypes and vice versa under two successive grafts over 63 days. In addition, expression of the inserted gene was maintained, being functional without eliciting graft rejection. In conclusion, these results show that transplanting genetically-modified tissues into normal, syngeneic or genetically-modified recipient dogs with different mtDNA haplotypes do not elicit skin graft rejection or affect expression of the inserted gene. Therefore, therapeutically valuable tissue derived from SCNT with genetic modification might be used safely in clinical applications for patients with diseased tissues. PMID:25372489

  14. Detection of a new submicroscopic Norrie disease deletion interval with a novel DNA probe isolated by differential Alu PCR fingerprint cloning

    NARCIS (Netherlands)

    Bergen, A. A.; Wapenaar, M. C.; Schuurman, E. J.; Diergaarde, P. J.; Lerach, H.; Monaco, A. P.; Bakker, E.; Bleeker-Wagemakers, E. M.; van Ommen, G. J.

    1993-01-01

    Differential Alu PCR fingerprint cloning was used to isolate a DNA probe from the Xp11.4-->p11.21 region of the human X chromosome. This novel sequence, cpXr318 (DXS742), detects a new submicroscopic deletion interval at the Norrie disease locus (NDP). Combining our data with the consensus genetic

  15. Molecular cloning of cDNA for the human tumor-associated antigen CO-029 and identification of related transmembrane antigens

    International Nuclear Information System (INIS)

    Szala, S.; Kasai, Yasushi; Steplewski, Z.; Rodeck, U.; Koprowski, H.; Linnenbach, A.J.

    1990-01-01

    The human tumor-associated antigen CO-029 is a monoclonal antibody-defined cell surface glycoprotein of 27-34 kDa. By using the high-efficiency COS cell expression system, a full-length cDNA clone for CO-029 was isolated. When transiently expressed in COS cells, the cDNA clone directed the synthesis of an antigen reactive to monoclonal antibody CO-029 in mixed hemadsorption and immunoblot assays. Sequence analysis revealed that CO-029 belongs to a family of cell surface antigens that includes the melanoma-associated antigen ME491, the leukocyte cell surface antigen CD37, and the Sm23 antigen of the parasitic helminth Schistosoma mansoni. CO-029 and ME491 antigen expression and the effect of their corresponding monoclonal antibodies on cell growth were compared in human tumor cell lines of various histologic origins

  16. Production of acquired immunodeficiency syndrome-associated retrovirus in human and nonhuman cells transfected with an infectious molecular clone

    International Nuclear Information System (INIS)

    Adachi, A.; Gendelman, H.E.; Koenig, S.; Folks, T.; Willey, R.; Rabson, A.; Martin, M.A.

    1986-01-01

    The authors considered an infectious molecular clone of acquired immunodeficiency syndrome-associated retrovirus. Upon transfection, this clone directed the production of infectious virus particles in a wide variety of cells in addition to human T4 cells. The progeny, infectious virions, were synthesized in mouse, mink, monkey, and several human non-T cell lines, indicating the absence of any intracellular obstacle to viral RNA or protein production or assembly. During the course of these studies, a human colon carcinoma cell line, exquisitely sensitive to DNA transfection, was identified

  17. Skewed X-inactivation in cloned mice

    International Nuclear Information System (INIS)

    Senda, Sho; Wakayama, Teruhiko; Yamazaki, Yukiko; Ohgane, Jun; Hattori, Naka; Tanaka, Satoshi; Yanagimachi, Ryuzo; Shiota, Kunio

    2004-01-01

    In female mammals, dosage compensation for X-linked genes is accomplished by inactivation of one of two X chromosomes. The X-inactivation ratio (a percentage of the cells with inactivated maternal X chromosomes in the whole cells) is skewed as a consequence of various genetic mutations, and has been observed in a number of X-linked disorders. We previously reported that phenotypically normal full-term cloned mouse fetuses had loci with inappropriate DNA methylation. Thus, cloned mice are excellent models to study abnormal epigenetic events in mammalian development. In the present study, we analyzed X-inactivation ratios in adult female cloned mice (B6C3F1). Kidneys of eight naturally produced controls and 11 cloned mice were analyzed. Although variations in X-inactivation ratio among the mice were observed in both groups, the distributions were significantly different (Ansary-Bradley test, P < 0.01). In particular, 2 of 11 cloned mice showed skewed X-inactivation ratios (19.2% and 86.8%). Similarly, in intestine, 1 of 10 cloned mice had a skewed ratio (75.7%). Skewed X-inactivation was observed to various degrees in different tissues of different individuals, suggesting that skewed X-inactivation in cloned mice is the result of secondary cell selection in combination with stochastic distortion of primary choice. The present study is the first demonstration that skewed X-inactivation occurs in cloned animals. This finding is important for understanding both nuclear transfer technology and etiology of X-linked disorders

  18. Telomeres and the ethics of human cloning.

    Science.gov (United States)

    Allhoff, Fritz

    2004-01-01

    In search of a potential problem with cloning, I investigate the phenomenon of telomere shortening which is caused by cell replication; clones created from somatic cells will have shortened telomeres and therefore reach a state of senescence more rapidly. While genetic intervention might fix this problem at some point in the future, I ask whether, absent technological advances, this biological phenomenon undermines the moral permissibility of cloning.

  19. Clip, connect, clone

    DEFF Research Database (Denmark)

    Fujima, Jun; Lunzer, Aran; Hornbæk, Kasper

    2010-01-01

    using three mechanisms: clipping of input and result elements from existing applications to form cells on a spreadsheet; connecting these cells using formulas, thus enabling result transfer between applications; and cloning cells so that multiple requests can be handled side by side. We demonstrate...

  20. Molecular analysis of Toxoplasma gondii Surface Antigen 1 (SAG1) gene cloned from Toxoplasma gondii DNA isolated from Javanese acute toxoplasmosis

    Science.gov (United States)

    Haryati, Sri; Agung Prasetyo, Afiono; Sari, Yulia; Dharmawan, Ruben

    2018-05-01

    Toxoplasma gondii Surface Antigen 1 (SAG1) is often used as a diagnostic tool due to its immunodominant-specific as antigen. However, data of the Toxoplasma gondii SAG1 protein from Indonesian isolate is limited. To study the protein, genomic DNA was isolated from a Javanese acute toxoplasmosis blood samples patient. A complete coding sequence of Toxoplasma gondii SAG1 was cloned and inserted into an Escherichia coli expression plasmid and sequenced. The sequencing results were subjected to bioinformatics analysis. The Toxoplasma gondii SAG1 complete coding sequences were successfully cloned. Physicochemical analysis revealed the 336 aa of SAG1 had 34.7 kDa of weight. The isoelectric point and aliphatic index were 8.4 and 78.4, respectively. The N-terminal methionine half-life in Escherichia coli was more than 10 hours. The antigenicity, secondary structure, and identification of the HLA binding motifs also had been discussed. The results of this study would contribute information about Toxoplasma gondii SAG1 and benefits for further works willing to develop diagnostic and therapeutic strategies against the parasite.

  1. Cloning of Soluble Human Stem Cell Factor in pET-26b(+) Vector.

    Science.gov (United States)

    Asghari, Salman; Shekari Khaniani, Mahmoud; Darabi, Masood; Mansoori Derakhshan, Sima

    2014-01-01

    Stem cell factor (SCF) plays an important role in the survival, proliferation and differentiation of hematopoietic stem cells and progenitor cells. Potential therapeutic applications of SCF include hematopoietic stem cell mobilization, exvivo stem/progenitor cell expansion, gene therapy, and immunotherapy. Considering the cost and problem in accessibility of this product in Iran, clears the importance of indigenizing production of rhSCF. In the present work, we describe the construction of the soluble rhSCF expression vector in pET-26b (+) with periplasmic localization potential. Following PCR amplification of human SCF ORF, it is cloned in pET-26b (+) vector in NcoI and XhoI sites. The recombinant construct was transformed into BL21 (DE3) Ecoli strains. The construction of recombinant vector was verified by colony PCR and sequence analysis of pET26b-hSCF vector. Sequence analyses proved that human SCF ORF has been inserted into NcoI and XhoI site with correct orientation downstream of strong T7 promotor and showed no nucleotide errors. The SCF ORF was successfully cloned in pET-26b (+) expression vector and is ready for future production of SCF protein.

  2. Three concepts of cloning in human beings.

    Science.gov (United States)

    Cui, Ke-Hui

    2005-07-01

    Human cloning, organ cloning and tissue cloning are various types of cloning that occur at different levels with different methodologies. According to three standards of terminology for an embryo (fertilization through germ cells, development in the uterus and having the potential to produce a human life), tissue cloning and type I organ cloning will not produce an embryo. In contrast, human cloning and type II organ cloning will produce an embryo. Thus, only non-germinal tissue cloning and type I organ cloning are beyond the ethical question and will not change human beings as a species. Using cloned tissues to make new tissues or organs is promising for the future of medicine.

  3. Failure of anti-T-cell receptor V beta antibodies to consistently identify a malignant T-cell clone in Sézary syndrome.

    Science.gov (United States)

    Bigler, R D; Boselli, C M; Foley, B; Vonderheid, E C

    1996-11-01

    Monoclonal antibodies (MAbs) reacting with the human T cell receptor (TCR) V beta or V alpha region have been shown to be almost as specific as a private idiotypic MAb in identifying T cell clones. When available, V beta-specific MAbs offer the ease of immunofluorescence analysis to identify and quantitate expanded malignant or nonmalignant T cell populations without requiring polymerase chain reaction (PCR) technology to evaluate expression of V beta gene families. The V beta expression of peripheral blood lymphocytes from twenty-three consecutive patients with Sézary syndrome has been analyzed by reverse transcriptase (RT)-PCR. Ten patients had malignant T cell clones that expressed a TCR V beta corresponding to a commercially available anti-V beta antibody. Immunofluorescence staining with anti-V beta MAbs showed a direct correlation with RT-PCR results in seven of ten patients. No false positive reactivity was noted on immunofluorescence staining with any MAb. Cells from three patients, however, did not react with the corresponding anti-V beta MAb. These three cases expressed a TCR V beta from gene families containing a single member, ie, V beta 14, V beta 18, and V beta 20, yet MAbs reported to be specific for these regions failed to react with the T cell clone from these patients. Sequencing of the PCR product in these cases confirmed the RT-PCR results. Cells from two patients expressed a TCR using V beta 5.1-D beta 1.1 genes with different J-C segments. One patient's cells reacted with an anti-V beta 5.1 MAb (LC4) whereas the other patient's cells bound one-tenth the amount of this same MAb. These results indicate that currently available anti-TCR V region MAbs may not react consistently with T cell clones expressing the corresponding V region or may react with a low affinity making detection difficult. Differences in the J-C junction or in CDR3 may influence the binding of these MAbs. Until the false negative rate is reduced and the fine specificity and

  4. Chromosome microdissection and cloning in human genome and genetic disease analysis

    International Nuclear Information System (INIS)

    Kao, Faten; Yu, Jingwei

    1991-01-01

    A procedure has been described for microdissection and microcloning of human chromosomal DNA sequences in which universal amplification of the dissected fragments by Mbo I linker adaptor and polymerase chain reaction is used. A very large library comprising 700,000 recombinant plasmid microclones from 30 dissected chromosomes of human chromosome 21 was constructed. Colony hybridization showed that 42% of the clones contained repetitive sequences and 58% contained single or low-copy sequences. The insert sizes generated by complete Mbo I cleavage ranged from 50 to 1,100 base pairs with a mean of 416 base pairs. Southern blot analysis of microclones from the library confirmed their human origin and chromosome 21 specificity. Some of these clones have also been regionally mapped to specific sites of chromosome 21 by using a regional mapping panel of cell hybrids. This chromosome microtechnology can generate large numbers of microclones with unique sequences from defined chromosomal regions and can be used for processes such as (i) isolating corresponding yeast artificial chromosome clones with large inserts, (ii) screening various cDNA libraries for isolating expressed sequences, and (iii) constructing region-specific libraries of the entire human genome. The studies described here demonstrate the power of this technology for high-resolution genome analysis and explicate their use in an efficient search for disease-associated genes localized to specific chromosomal regions

  5. [Cloning goat producing human lactoferrin with genetically modified donor cells selected by single or dual markers].

    Science.gov (United States)

    An, Liyou; Yuan, Yuguo; Yu, Baoli; Yang, Tingjia; Cheng, Yong

    2012-12-01

    We compared the efficiency of cloning goat using human lactoferrin (hLF) with genetically modified donor cells marked by single (Neo(r)) or double (Neo(r)/GFP) markers. Single marker expression vector (pBLC14) or dual markers expression vector (pAPLM) was delivered to goat fetal fibroblasts (GFF), and then the transgenic GFF was used as donor cells to produce transgenic goats. Respectively, 58.8% (20/34) and 86.7% (26/30) resistant cell lines confirmed the transgenic integration by PCR. Moreover, pAPLM cells lines were subcultured with several passages, only 20% (6/30) cell lines was observed fluorescence from each cell during the cell passage. Somatic cell nuclear transfer using the donor cells harbouring pBLC14 or pAPLM construct, resulting in a total of 806 reconstructed embryos, a pregnancy rate at 35 d (53.8%, 39.1%) and 60 d (26.9%, 21.7%), and an offspring birth rate (1.9%, 1.4%) with 5 and 7 newborn cloned goats, respectively. Transgene was confirmed by PCR and southern-blot in all cloned offspring. There were no significant differences at the reconstructed embryo fusion rates, pregnancy rates and the birth rate (P > 0.05) between single and double markers groups. The Neo(r)/GFP double markers could improve the reliability for accurately and efficiently selecting the genetically modified donor cells. No adverse effect was observed on the efficiency of transgenic goat production by SCNT using somatic cells transfected with double (Neo(r)/GFP) markers vector.

  6. Cloning and characterization of human RTVP-1b, a novel splice variant of RTVP-1 in glioma cells

    International Nuclear Information System (INIS)

    Xiang Cunli; Sarid, Ronit; Cazacu, Simona; Finniss, Susan; Lee, Hae-Kyung; Ziv-Av, Amotz; Mikkelsen, Tom; Brodie, Chaya

    2007-01-01

    Here, we report the cloning and characterization of RTVP-1b, a novel splice variant of human RTVP-1, which was isolated from the U87 glioma cell line. Sequence analysis revealed that RTVP-1b contains an additional 71 base exon between exons 2 and 3 that is missing in RTVP-1, leading to a frame-shift and a different putative protein. The deduced protein was 237 amino acids in length, sharing the N-terminal 141 amino acids with RTVP-1. RT-PCR analysis demonstrated that RTVP-1b was expressed in a wide range of tissues and that its expression was different from that of RTVP-1. In contrast, RTVP-1 and RTVP-1b showed similar patterns of expression in astrocytic tumors; highly expressed in glioblastomas as compared to normal brains, low-grade astrocytomas and anaplastic oligodendrogliomas. Overexpression of RTVP-1b increased glioma cell proliferation but did not affect cell migration. Our results suggest that RTVP-1b represents a potential prognostic marker and therapeutic target in gliomas

  7. Rapid isolation of antibody from a synthetic human antibody library by repeated fluorescence-activated cell sorting (FACS.

    Directory of Open Access Journals (Sweden)

    Sung Sun Yim

    Full Text Available Antibodies and their derivatives are the most important agents in therapeutics and diagnostics. Even after the significant progress in the technology for antibody screening from huge libraries, it takes a long time to isolate an antibody, which prevents a prompt action against the spread of a disease. Here, we report a new strategy for isolating desired antibodies from a combinatorial library in one day by repeated fluorescence-activated cell sorting (FACS. First, we constructed a library of synthetic human antibody in which single-chain variable fragment (scFv was expressed in the periplasm of Escherichia coli. After labeling the cells with fluorescent antigen probes, the highly fluorescent cells were sorted by using a high-speed cell sorter, and these cells were reused without regeneration in the next round of sorting. After repeating this sorting, the positive clones were completely enriched in several hours. Thus, we screened the library against three viral antigens, including the H1N1 influenza virus, Hepatitis B virus, and Foot-and-mouth disease virus. Finally, the potential antibody candidates, which show K(D values between 10 and 100 nM against the target antigens, could be successfully isolated even though the library was relatively small (∼ 10(6. These results show that repeated FACS screening without regeneration of the sorted cells can be a powerful method when a rapid response to a spreading disease is required.

  8. Cloning of T lymphocytes from bronchoalveolar lavage fluid

    NARCIS (Netherlands)

    Hol, B. E.; Krouwels, F. H.; Bruinier, B.; Reijneke, R. M.; Mengelers, H. J.; Koenderman, L.; Jansen, H. M.; Out, T. A.

    1992-01-01

    We have prepared T-cell clones from bronchoalveolar lavage fluid (BALF) from four healthy, nonsmoking persons and from four patients with allergic asthma. T cells were cloned by direct limiting dilution and with the use of a fluorescent activated cell sorter with an automated cell deposition unit.

  9. Human Cloning

    National Research Council Canada - National Science Library

    Johnson, Judith A; Williams, Erin D

    2006-01-01

    .... Scientists in other labs, including Harvard University and the University of California at San Francisco, intend to produce cloned human embryos in order to derive stem cells for medical research...

  10. Human terminal deoxyribonucleotidyltransferase: molecular cloning and structural analysis of the gene and 5' flanking region

    International Nuclear Information System (INIS)

    Riley, L.K.; Morrow, J.K.; Danton, M.J.; Coleman, M.S.

    1988-01-01

    Human terminal deoxyribonucleotidyltransferase cDNA contains an open reading frame of 1530 base pairs (bp) corresponding to a protein containing 510 amino acids. The encoded protein is a template-independent DNA polymerase found only in a restricted population of normal and malignant prelymphocytes. To begin to investigate the genetic elements responsible for the tissue-specific expression of terminal deoxyribonucleotidyltransferase, genomic clones, containing the entire human gene were isolated and characterized. Initially, cDNA clones were isolated from a library generated from the human lymphoblastoid cell line, MOLT-4R. A cDNA clone containing the entire coding region of the protein was used to isolate a series of overlapping clones from two human genomic libraries. The gene comprises 11 exons and 10 introns and spans 49.4 kilobases. The 5' flanking region (709 bp) including exon 1 was sequenced. Several putative transcription initiation sites were mapped. Within 500 nucleotides of the translation start site, a series of promoter elements was detected. TATA and CAAT sequences, respectively, were found to start at nucleotides -185 and -204, -328 and -370, and -465 and -505. Start sites were found for a cyclic AMP-dependent promoter analog at nucleotide -121, an eight-base sequence corresponding to the IgG promoter enhancer (cd) at nucleotide -455, and an analog of the IgG promoter (pd) at nucleotide -159. These findings suggest that transcripts coding for terminal deoxyribonucleotidyltransferase may be variable in length and that transcription may be influenced by a variety of genetic elements

  11. Therapeutic cloning in the mouse

    Science.gov (United States)

    Mombaerts, Peter

    2003-01-01

    Nuclear transfer technology can be applied to produce autologous differentiated cells for therapeutic purposes, a concept termed therapeutic cloning. Countless articles have been published on the ethics and politics of human therapeutic cloning, reflecting the high expectations from this new opportunity for rejuvenation of the aging or diseased body. Yet the research literature on therapeutic cloning, strictly speaking, is comprised of only four articles, all in the mouse. The efficiency of derivation of embryonic stem cell lines via nuclear transfer is remarkably consistent among these reports. However, the efficiency is so low that, in its present form, the concept is unlikely to become widespread in clinical practice. PMID:12949262

  12. Evidence of heterogeneity within bovine satellite cells isolated from young and adult animals.

    Science.gov (United States)

    Li, J; Gonzalez, J M; Walker, D K; Hersom, M J; Ealy, A D; Johnson, S E

    2011-06-01

    Satellite cells are a heterogeneous population of myogenic precursors responsible for muscle growth and repair in mammals. The objectives of the experiment were to examine the growth rates and degree of heterogeneity within bovine satellite cells (BSC) isolated from young and adult animals. The BSC were harvested from the semimembranosus of young (4.3 ± 0.5 d) and adult (estimated 24 to 27 mo) cattle and cultured en masse. Young animal BSC re-enter the cell cycle sooner and reach maximal 5-ethynyl-2'-deoxyuridine (EdU) incorporation earlier (P animals after 3, 4, and 5 d in culture. These results indicate that BSC from young animals activate, proliferate, and differentiate sooner than isolates from adult animals. Lineage heterogeneity within BSC was examined using antibodies specific for Pax7 and Myf5, lineage markers of satellite cells, and myoblasts. Immunocytochemistry revealed the majority of Pax7-expressing BSC also express Myf5; a minor population (~5%) fails to exhibit Myf5 immunoreactivity. The percentage of Pax7:Myf5 BSC from young animals decreases sooner (P cell clones were established and analyzed after 10 d. Colonies segregated into 2 groups based upon population doubling time. Immunostaining of the slow-growing colonies (population doubling time ≥ 3 d) revealed that a portion exhibited asymmetric distribution of the lineage markers Pax7 and Myf5, similar to self-renewable mouse muscle stem cells. In summary, these results offer insight into the heterogeneity of BSC and provide evidence for subtle differences between rodent and bovine myogenic precursors.

  13. Statement on Human Cloning

    Science.gov (United States)

    ... as our understanding of this technology advances. Support Stem Cell Research (including Research Cloning) AAAS supports stem cell research, including the use of nuclear transplantation techniques (also ...

  14. Molecular Cloning and Sequencing of AlkalophilicCellulosimicrobium cellulans CKMX1 Xylanase Gene Isolated from Mushroom Compost and Characterization of the Gene Product

    Directory of Open Access Journals (Sweden)

    Abhishek Walia

    2015-12-01

    Full Text Available ABSTRACT A xylanolytic bacterium was isolated from mushroom compost by using enrichment technique. Results from the metabolic fingerprinting, whole-cell fatty acids methyl ester analysis and 16S rDNA sequencing suggested the bacterium to be Cellulosimicrobium cellulans CKMX1. Due to the xylanolytic activity of this bacterium, isolation and characterization of the xylanase gene were attempted. A distinct fragment of about 1671 bp was successfully amplified using PCR and cloned into Escherichia coli DH5α. A BLAST search confirmed that the DNA sequence from the amplified fragment was endo-1, 4-beta-xylanase, which was a member of glycoside hydrolase family 11. It showed 98% homology withCellulosimicrobium sp. xylanase gene (Accession no. FJ859907.1 reported from the gut of Eisenia fetida in Korea. In silicophysico-chemical characterization of amino acid sequence of xylanase showed an open reading frame encoding a 556 amino acid sequence with a molecular weight of 58 kDa and theoretical isolectric point (pI of 4.46 was computed using Expasy's ProtParam server. Secondary and homology based 3D structure of xylanase was analysed using SOPMA and Swiss-Prot software.

  15. Clonal analysis of the T-cell response to in vivo expressed Mycobacterium tuberculosis protein Rv2034, using a CD154 expression based T-cell cloning method.

    Directory of Open Access Journals (Sweden)

    Susanna Commandeur

    Full Text Available Tuberculosis (TB, caused by Mycobacterium tuberculosis (Mtb, remains a leading cause of death worldwide. A better understanding of the role of CD4+ and CD8+ T cells, which are both important to TB protection, is essential to unravel the mechanisms of protection and to identify the key antigens seen by these T cells. We have recently identified a set of in vivo expressed Mtb genes (IVE-TB which is expressed during in vivo pulmonary infection in mice, and shown that their encoded antigens are potently recognized by polyclonal T cells from tuberculin skin test-positive, in vitro ESAT-6/CFP10-responsive individuals. Here we have cloned T cells specific for one of these newly identified in vivo expressed Mtb (IVE-TB antigens, Rv2034. T cells were enriched based on the expression of CD154 (CD40L, which represents a new method for selecting antigen-specific (low frequency T cells independent of their specific function. An Rv2034-specific CD4+ T-cell clone expressed the Th1 markers T-bet, IFN-γ, TNF-α, IL-2 and the cytotoxicity related markers granzyme B and CD107a as measured by flow cytometry. The clone specifically recognized Rv2034 protein, Rv2034 peptide p81-100 and Mtb lysate. Remarkably, while the recognition of the dominant p81-100 epitope was HLA-DR restricted, the T-cell clone also recognized a neighboring epitope (p88-107 in an HLA-DR- as well as HLA-DQ1-restricted fashion. Importantly, the T-cell clone was able to inhibit Mtb outgrowth from infected monocytes significantly. The characterization of the polyfunctional and Mtb inhibitory T-cell response to IVE-TB Rv2034 at the clonal level provides detailed further insights into the potential of IVE-TB antigens as new vaccine candidate antigens in TB. Our new approach allowed the identification of T-cell subsets that likely play a significant role in controlling Mtb infection, and can be applied to the analysis of T-cell responses in patient populations.

  16. Novel Technology for Cloning Prostate Cancer Cell Markers

    National Research Council Canada - National Science Library

    Bancroft, F

    2002-01-01

    The purpose of the project is to employ probes isolated from the LNCaP series of human prostate cancer cells, to probe human cDNA microarrays, so as to investigate genes differentially expressed among these cell lines...

  17. Molecular cloning and characterization of genes required for nucleotide excision repair in yeast

    International Nuclear Information System (INIS)

    Friedberg, E.C.

    1987-01-01

    Nucleotide excision repair in the yeast S. cerevisiae is a complex process which involves a large number of genes. At least five of these genes (RAD1, RAD2, RAD3, RAD4 and RAD10) are absolutely required for this process and mutations in any of these genes result in no detectable excision repair in vivo. In order to understand the function of these genes in DNA repair, the authors isolated a number of them by screening a yeast genomic library for recombinant plasmids which complement the phentoype of sensitivity to ultraviolet (UV) radiation imparted to mutant strains. A plasmid containing the RAD4 gene was isolated by an alternative strategy which will be discussed. The cloned genes have been extensively characterized. It has been determined that the RAD3 gene is essential for the viability of haploid yeast cells in the absence of DNA damage. The RAD2 gene is inducible by treatment of cells with a variety of DNA-damaging agents, including UV radiation and ionizing radiation. The RAD10 gene shares considerable amino acid sequence homology with a cloned gene involved in nucleotide excision repair in human cells. Yeast is a particularly versatile organism for studying gene function by molecular and genetic approaches and emphasis is placed on many of the techniques used in the present studies

  18. Preservation and Reproduction of Microminipigs by Cloning Technology.

    Science.gov (United States)

    Enya, Satoko; Kawarasaki, Tatsuo; Otake, Masayoshi; Kangawa, Akihisa; Uenishi, Hirohide; Mikawa, Satoshi; Nishimura, Takashi; Kuwahawa, Yasushi; Shibata, Masatoshi

    Microminipigs have been maintained in small populations of closed colonies, involving risks of inbreeding depression and genetic drift. In order to avoid these risks, we assessed the applicability of cloning technology. Male and female clones were produced from a stock of cryopreserved somatic cells, obtaining offspring by means of natural mating. Phenotypic and genotypic characteristics of original microminipigs, clones and their offspring were analyzed and recorded. Clones presented characteristics similar to those of the cell-stock data. Although the body weight of clones tended to be heavier than that of the cell-stock data, body weights of their offspring were similar to those of previous reports. Thus, cloned microminipigs have the potential to be a valuable genetic resource for reproduction and breeding. Our proposed methodology might be useful to provide a large number of animals with adequate quality from a limited population with sufficient genetic diversity. Copyright © 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  19. B-cell stimulating factor

    Energy Technology Data Exchange (ETDEWEB)

    Clevenger, W R; Conlon, P J; Eisenman, J R; Gillis, S; Grabstein, K H; Hopp, T P; March, C J; Mochizuki, D Y; Price, V L; Shanebeck, K D

    1987-10-05

    BSF-1 was derived from malignant cells and purified by use of various techniques, including adsorption, ion exchange chromatography and reverse phase high performance liquid chromatography. By these techniques, the BSF-1 was purified to homogenity. The high purification of the BSF-1 has made possible the sequencing of the amino acid residues at the N-terminal portion of its protein molecules. From the amino acid sequencing information, a radiolabelled oligonucleotide probe corresponding to portion of the amino acid sequence of the BSF-1 molecule was synthesized and then used to probe a cDNA library prepared from polyadenylated mRNA extracted from cell lines known to produce BSF-1. Through this procedure, a cDNA clone containing the BSF-1 gene was isolated, sequenced and mature BSF-1 expressed. The isolated cDNA clone was then radiolabelled and used as a large probe for screening cDNA libraries of other species of animals for homologous BSF-1 clones.

  20. Tetranectin, a plasminogen kringle 4-binding protein. Cloning and gene expression pattern in human colon cancer

    DEFF Research Database (Denmark)

    Wewer, U M; Albrechtsen, R

    1992-01-01

    BACKGROUND: Tetranectin is a recently discovered protein that binds to kringle 4 region of plasminogen (Clemmensen I, Petersen LC, Kluft C. Eur J Biochem 1986; 156:327. EXPERIMENTAL DESIGN: The mRNA encoding human tetranectin was cloned by using degenerate primers in a reverse transcriptase...... reaction followed by polymerase chain reaction amplification. The resulting polymerase chain reaction product was examined by DNA sequencing and subsequently used as probe for screening a human placental cDNA library. A full length cDNA clone (TET-1) was isolated, characterized, and used for Northern blot...... prominent in the lungs and spleen. No hybridization signal was detected in three carcinoma cell lines examined in parallel. Northern blot analysis of poly A+ RNA isolated from solid tumors revealed a tetranectin specific mRNA band. In situ hybridizations on tissue sections of colon carcinomas and normal...

  1. Cloning Mice.

    Science.gov (United States)

    Ogura, Atsuo

    2017-08-01

    Viable and fertile mice can be generated by somatic nuclear transfer into enucleated oocytes, presumably because the transplanted somatic cell genome becomes reprogrammed by factors in the oocyte. The first somatic cloned offspring of mice were obtained by directly injecting donor nuclei into recipient enucleated oocytes. When this method is used (the so-called Honolulu method of somatic cell nuclear transfer [SCNT]), the donor nuclei readily and completely condense within the enucleated metaphase II-arrested oocytes, which contain high levels of M-phase-promoting factor (MPF). It is believed that the condensation of the donor chromosomes promotes complete reprogramming of the donor genome within the mouse oocytes. Another key to the success of mouse cloning is the use of blunt micropipettes attached to a piezo impact-driving micromanipulation device. This system saves a significant amount of time during the micromanipulation of oocytes and thus minimizes the loss of oocyte viability in vitro. For example, a group of 20 oocytes can be enucleated within 10 min by an experienced operator. This protocol is composed of seven parts: (1) preparing micropipettes, (2) setting up the enucleation and injection micropipettes, (3) collecting and enucleating oocytes, (4) preparing nucleus donor cells, (5) injecting donor nuclei, (6) activating embryos and culturing, and (7) transferring cloned embryos. © 2017 Cold Spring Harbor Laboratory Press.

  2. New Approaches to Attenuated Hepatitis a Vaccine Development: Cloning and Sequencing of Cell-Culture Adapted Viral cDNA.

    Science.gov (United States)

    1987-10-13

    after multiple passages in vivo and in vitro. J. Gen. Virol. 67, 1741- 1744. Sabin , A.B. (1985). Oral poliovirus vaccine : history of its development...IN (N NEW APPROACHES TO ATTENUATED HEPATITIS A VACCINE DEVELOPMENT: Q) CLONING AND SEQUENCING OF CELL-CULTURE ADAPTED VIRAL cDNA I ANNUAL REPORT...6ll02Bsl0 A 055 11. TITLE (Include Security Classification) New Approaches to Attenuated Hepatitis A Vaccine Development: Cloning and Sequencing of Cell

  3. Phenotypic and molecular characterization of Neisseria gonorrhoeae isolates from Slovenia, 2006-12: rise and fall of the multidrug-resistant NG-MAST genogroup 1407 clone?

    Science.gov (United States)

    Jeverica, Samo; Golparian, Daniel; Matičič, Mojca; Potočnik, Marko; Mlakar, Boštjan; Unemo, Magnus

    2014-06-01

    To determine the phenotypic and molecular characteristics of Neisseria gonorrhoeae isolates obtained between 2006 and 2012 in Slovenia. Gonococcal isolates obtained between 2006 and 2012 in Slovenia (n = 194) were investigated with Etest for susceptibility to cefixime, ceftriaxone, penicillin, ciprofloxacin, azithromycin, tetracycline, gentamicin and spectinomycin. All isolates were examined with N. gonorrhoeae multiantigen sequence typing for molecular epidemiology and sequencing of the major extended-spectrum cephalosporin (ESC) resistance determinants (penA, mtrR and penB) was performed. The overall prevalence of decreased susceptibility or resistance to cefixime and ceftriaxone (MIC ≥0.125 mg/L) was 11% and 5%, respectively. The decreased susceptibility or resistance showed an epidemic peak in 2011 (33% for cefixime and 11% for ceftriaxone), decreasing to 6% and 4%, respectively, in 2012. ST1407 (9% of isolates), ST21 (6%) and ST225 (6%) were the most common sequence types (STs) during 2006-12. Genogroup G1407 (ST1407 most prevalent ST), an internationally spread clone with decreased susceptibility or resistance to ESCs, was most prevalent (48%) in 2009. However, the G1407 prevalence then declined: in 2010, 30%; in 2011, 28%; and in 2012, 8%. Instead, in 2012 the ESC- and ciprofloxacin-susceptible G21 was the predominant genogroup (26%). The prevalence of gonococcal resistance to ESCs in Slovenia has been high, but fluctuating. Fortunately, in 2012 some ESC- and ciprofloxacin-susceptible clones, such as genogroups G21, G1195 and G2992, appeared to have mainly replaced the multidrug-resistant G1407 clone, a replacement also seen in several European countries. © The Author 2014. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  4. Gene editing and clonal isolation of human induced pluripotent stem cells using CRISPR/Cas9.

    Science.gov (United States)

    Yumlu, Saniye; Stumm, Jürgen; Bashir, Sanum; Dreyer, Anne-Kathrin; Lisowski, Pawel; Danner, Eric; Kühn, Ralf

    2017-05-15

    Human induced pluripotent stem cells (hiPSCs) represent an ideal in vitro platform to study human genetics and biology. The recent advent of programmable nucleases makes also the human genome amenable to experimental genetics through either the correction of mutations in patient-derived iPSC lines or the de novo introduction of mutations into otherwise healthy iPSCs. The production of specific and sometimes complex genotypes in multiple cell lines requires efficient and streamlined gene editing technologies. In this article we provide protocols for gene editing in hiPSCs. We presently achieve high rates of gene editing at up to three loci using a modified iCRISPR system. This system includes a doxycycline inducible Cas9 and sgRNA/reporter plasmids for the enrichment of transfected cells by fluorescence-activated cell sorting (FACS). Here we cover the selection of target sites, vector construction, transfection, and isolation and genotyping of modified hiPSC clones. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Infectious Maize rayado fino virus from cloned cDNA

    Science.gov (United States)

    Maize rayado fino virus (MRFV) is the type member of the marafiviruses within the family Tymoviridae. A cDNA clone from which infectious RNA can be transcribed was produced from a US isolate of MRFV (MRFV-US). Infectivity of transcripts derived from cDNA clones was demonstrated by infection of mai...

  6. Cloning, identification, and functional analysis of bone marrow stromal cell antigen-2 from sika deer (Cervus nippon).

    Science.gov (United States)

    Wang, Jiawen; Bian, Shuai; Liu, Meichun; Zhang, Xin; Wang, Siming; Bai, Xueyuan; Zhao, Daqing; Zhao, Yu

    2018-06-30

    BST-2(tetherin/CD317/HM1.24) has been identified as a cellular antiviral factor that inhibits the release of a wide range of enveloped viruses from infected cells. Orthologs of BST-2 have been identified in several species including humans, monkeys, cows, sheep, pigs, and mice. In this study, we cloned the gene and characterized the protein of the BST-2 homolog from sika deer (Cervus nippon). cnBST-2 shares 37.8% and 74.2% identity with the BST-2 homologs from Homo sapiens and Ovis aries, respectively. The extracellular domain of cnBST-2 has two putative N-linked glycosylation sites and three potential dimerization sites. cnBST-2 was shown to be expressed on the cell surface, like human BST-2. Exogenous expression of cnBST-2 resulted in potent inhibition of HIV-1 particle release in 293T cells; however, this activity resisted antagonism by HIV-1 Vpu. Moreover, cnBST-2 was not able to activate nuclear factor-κB, in contrast to human BST-2. This study is the first report of the isolation and characterization of BST-2 from C. nippon. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. Lessons learned from cloning dogs.

    Science.gov (United States)

    Kim, M J; Oh, H J; Kim, G A; Park, J E; Park, E J; Jang, G; Ra, J C; Kang, S K; Lee, B C

    2012-08-01

    The aim of this article is to review dog cloning research and to suggest its applications based on a discussion about the normality of cloned dogs. Somatic cell nuclear transfer was successfully used for production of viable cloned puppies despite limited understanding of in vitro dog embryo production. Cloned dogs have similar growth characteristics to those born from natural fertilization, with no evidence of serious adverse effects. The offspring of cloned dogs also have similar growth performance and health to those of naturally bred puppies. Therefore, cloning in domestic dogs can be applied as an assisted reproductive technique to conserve endangered species, to treat sterile canids or aged dogs, to improve reproductive performance of valuable individuals and to generate disease model animals. © 2012 Blackwell Verlag GmbH.

  8. ddClone: joint statistical inference of clonal populations from single cell and bulk tumour sequencing data.

    Science.gov (United States)

    Salehi, Sohrab; Steif, Adi; Roth, Andrew; Aparicio, Samuel; Bouchard-Côté, Alexandre; Shah, Sohrab P

    2017-03-01

    Next-generation sequencing (NGS) of bulk tumour tissue can identify constituent cell populations in cancers and measure their abundance. This requires computational deconvolution of allelic counts from somatic mutations, which may be incapable of fully resolving the underlying population structure. Single cell sequencing (SCS) is a more direct method, although its replacement of NGS is impeded by technical noise and sampling limitations. We propose ddClone, which analytically integrates NGS and SCS data, leveraging their complementary attributes through joint statistical inference. We show on real and simulated datasets that ddClone produces more accurate results than can be achieved by either method alone.

  9. Cloning and Characterization of Genes that Inhibit TRAIL-Induced Apoptosis of Breast Cancer Cells

    National Research Council Canada - National Science Library

    Shu, Hong-Bing

    2003-01-01

    ...). However, some cancer cells are resistant to TRAIL-induced apoptosis (3, 4, 6-13). The purpose of this proposed study is to clone and characterize such inhibitory genes of TRAIL-induced apoptosis...

  10. Cloning higher plants from aseptically cultured tissues and cells

    Science.gov (United States)

    Krikorian, A. D.

    1982-01-01

    A review of aseptic culture methods for higher plants is presented, which focuses on the existing problems that limit or prevent the full realization of cloning plants from free cells. It is shown that substantial progress in clonal multiplication has been made with explanted stem tips or lateral buds which can be stimulated to produce numerous precocious axillary branches. These branches can then be separated or subdivided and induced to root in order to yield populations of genetically and phenotypically uniorm plantlets. Similarly, undifferentiated calluses can sometimes be induced to form shoots and/or roots adventitiously. Although the cell culture techniques required to produce somatic embryos are presently rudimentary, steady advances are being made in learning how to stimulate formation of somatic or adventive embryos from totipotent cells grown in suspension cultures. It is concluded that many problems exist in the producing and growing of totipotent or morphogenetically competent cell suspensions, but the potential benefits are great.

  11. Dissection of pathways leading to antigen receptor-induced and Fas/CD95-induced apoptosis in human B cells

    NARCIS (Netherlands)

    Lens, S. M.; den Drijver, B. F.; Pötgens, A. J.; Tesselaar, K.; van Oers, M. H.; van Lier, R. A.

    1998-01-01

    To dissect intracellular pathways involved in B cell Ag receptor (BCR)-mediated and Fas-induced human B cell death, we isolated clones of the Burkitt lymphoma cell line Ramos with different apoptosis sensitivities. Selection for sensitivity to Fas-induced apoptosis also selected for clones with

  12. An allospecific murine T helper clone which can help both T and B cell responses in vitro and in vivo

    DEFF Research Database (Denmark)

    Crispe, I N; Gascoigne, N R; Owens, T

    1984-01-01

    . Here we describe an in vitro and in vivo study of this problem, using a Th clone, designated MTH-1. The clone carries the cell surface markers Thy-1 and L3T4a, but lacks Lyt-2. It recognizes a minor alloantigen shared by DBA/2, B10.D2 and NZB spleen cells, and such recognition is restricted by H-2Ed...... in the polyclonal activation and maturation of the B cells to secrete immunoglobulin; also, antigen-primed B cells are augmented in their in vivo synthesis of specific antibody to the Thy-1 X 1 alloantigen by around 10(5) MTH-1 cells. Taken together, these results suggest a single Th clone can help both B cells......Both B lymphocytes and cytotoxic T lymphocytes respond to signals from the T helper (Th) compartment, and such signals are mediated by a number of biochemically distinct factors. This raises the question whether help for B cells and T cells is a function of one or several different kinds of Th cell...

  13. Highly leukemogenic radiation leukemia virus isolate is a thymotropic, immunosuppressive retrovirus with a unique RNA structure

    Energy Technology Data Exchange (ETDEWEB)

    Ben David, Y.; Kotler, M.; Yefenof, E.

    1987-04-15

    Clones of N-, B- and NB-fibrotropic viruses were isolated from weakly (D-RadLV) and strongly (A-RadLV) leukomogenic RadLV preparations. A highly leukemogenic, thymotropic virus (TV) was isolated by ex-vivo infection of thymocytes with A-RadLV. This virus could not be isolated from D-RadLV. Two-dimensional fingerprint analysis suggested that TV recombines unique RNA sequences with RNA genomic material derived from a B-tropic endogenous virus. C57BL/6 (B6) mice injected with B- or NB-fibrotropic clones, but not with TV or N-tropic viral clones, developed reactive T lymphocytes (Tr), capable of differentiating into anti-tumor cytotoxic cells. The N-tropic virus isolates were non-immunogenic in B6 mice whereas the TV isolate induced suppressor T lymphocytes (Ts) that abrogated a potential Tr response. These results suggest that emergence of highly leukemogenic RadLV involves activation of endogenous fibrotropic virus which is immunogenic in its natural host strain (B6). This virus can further recombine with other retroviral genetic sequences, resulting in a suppressogenic and thymotropic, highly leukemogenic virus.

  14. DNA fragmentation: manifestation of target cell destruction mediated by cytotoxic T-cell lines, lymphotoxin-secreting helper T-cell clones, and cell-free lymphotoxin-containing supernatant

    International Nuclear Information System (INIS)

    Schmid, D.S.; Tite, J.P.; Ruddle, N.H.

    1986-01-01

    A Lyt-2 + , trinitrophenyl-specific, lymphotoxin-secreting, cytotoxic T-cell line, PCl 55, mediates the digestion of target cell DNA into discretely sized fragments. This phenomenon manifests itself within 30 min after effector cell encounter as measured by the release of 3 H counts from target cells prelabeled with [ 3 H]deoxythymidine and occurs even at very low effector to target cell ratios (0.25:1). A Lyt-1 + , ovalbumin-specific, lymphotoxin-secreting T-helper cell clone, 5.9.24, is also able to mediate fragmentation of target cell DNA over a time course essentially indistinguishable from the cytotoxic T lymphocyte-mediated hit. Cell-free lymphotoxin-containing supernatants also cause release of DNA from targets, although they require a longer time course, on the order of 24 hr. In contrast, lysis of cells by antibody plus complement or Triton X-100 does not result in DNA release even after extended periods of incubation (24 hr). All three treatments that result in the release of DNA from cells cause fragmentation of that DNA into discretely sized pieces that are multiples of 200 base pairs. The results thus suggest that cytotoxic T cells, lymphotoxin-secreting helper clones with cytolytic activity, and lymphotoxin all effect target cell destruction by means of a similar mechanism and that observed differences in time course and the absence of target cell specificity in killing mediated by lymphotoxin may simply reflect differences in the mode of toxin delivery

  15. Isolation, cloning, and characterization of a partial novel aro A gene in common reed (Phragmites australis).

    Science.gov (United States)

    Taravat, Elham; Zebarjadi, Alireza; Kahrizi, Danial; Yari, Kheirollah

    2015-05-01

    Among the essential amino acids, phenylalanine, tryptophan, and tyrosine are aromatic amino acids which are synthesized by the shikimate pathway in plants and bacteria. Herbicide glyphosate can inhibit the biosynthesis of these amino acids. So, identification of the gene tolerant to glyphosate is very important. It has been shown that the common reed or Phragmites australis Cav. (Poaceae) is relatively tolerant to glyphosate. The aim of the current research is identification, cloning, sequencing, and registering of partial aro A gene of the common reed P. australis. The partial aro A gene of common reed (P. australis) was cloned in Escherichia coli and the amino acid sequence was identified/determined for the first time. This is the first report for isolation, cloning, and sequencing of a part of aro A gene from the common reed. A 670 bp fragment including two introns (86 bp and 289 bp) was obtained. The open reading frame (ORF) region in part of gene was encoded for 98 amino acids. Alignment showed high similarity among this region with Zea mays (L.) (Poaceae) (94.6%), Eleusine indica L. Gaertn (Poaceae) (94.2%), and Zoysia japonica Steud. (Poaceae) (94.2%). The alignment of amino acid sequence of the investigated part of the gene showed a homology with aro A from several other plants. This conserved region forms the enzyme active site. The alignment results of nucleotide and amino acid residues with related sequences showed that there are some differences among them. The relative glyphosate tolerance in the common reed may be related to these differences.

  16. Cloning of Soluble Human Stem Cell Factor in pET-26b(+ Vector

    Directory of Open Access Journals (Sweden)

    Salman Asghari

    2014-03-01

    Full Text Available Purpose: Stem cell factor (SCF plays an important role in the survival, proliferation and differentiation of hematopoietic stem cells and progenitor cells. Potential therapeutic applications of SCF include hematopoietic stem cell mobilization, exvivo stem/progenitor cell expansion, gene therapy, and immunotherapy. Considering the cost and problem in accessibility of this product in Iran, clears the importance of indigenizing production of rhSCF. In the present work, we describe the construction of the soluble rhSCF expression vector in pET-26b (+ with periplasmic localization potential. Methods: Following PCR amplification of human SCF ORF, it is cloned in pET-26b (+ vector in NcoI and XhoI sites. The recombinant construct was transformed into BL21 (DE3 Ecoli strains. Results: The construction of recombinant vector was verified by colony PCR and sequence analysis of pET26b-hSCF vector. Sequence analyses proved that human SCF ORF has been inserted into NcoI and XhoI site with correct orientation downstream of strong T7 promotor and showed no nucleotide errors. Conclusion: The SCF ORF was successfully cloned in pET-26b (+ expression vector and is ready for future production of SCF protein.

  17. The cell agglutination agent, phytohemagglutinin-L, improves the efficiency of somatic nuclear transfer cloning in cattle (Bos taurus).

    Science.gov (United States)

    Du, Fuliang; Shen, Perng-Chih; Xu, Jie; Sung, Li-Ying; Jeong, B-Seon; Lucky Nedambale, Tshimangadzo; Riesen, John; Cindy Tian, X; Cheng, Winston T K; Lee, Shan-Nan; Yang, Xiangzhong

    2006-02-01

    One of the several factors that contribute to the low efficiency of mammalian somatic cloning is poor fusion between the small somatic donor cell and the large recipient oocyte. This study was designed to test phytohemagglutinin (PHA) agglutination activity on fusion rate, and subsequent developmental potential of cloned bovine embryos. The toxicity of PHA was established by examining its effects on the development of parthenogenetic bovine oocytes treated with different doses (Experiment 1), and for different durations (Experiment 2). The effective dose and duration of PHA treatment (150 microg/mL, 20 min incubation) was selected and used to compare membrane fusion efficiency and embryo development following somatic cell nuclear transfer (Experiment 3). Cloning with somatic donor fibroblasts versus cumulus cells was also compared, both with and without PHA treatment (150 microg/mL, 20 min). Fusion rate of nuclear donor fibroblasts, after phytohemagglutinin treatment, was increased from 33 to 61% (P cell nuclear donors. The nuclear transfer (NT) efficiency per oocyte used was improved following PHA treatment, for both fibroblast (13% versus 22%) as well as cumulus cells (17% versus 34%; P cloned embryos, both with and without PHA treatment, were subjected to vitrification and embryo transfer testing, and resulted in similar survival (approximately 90% hatching) and pregnancy rates (17-25%). Three calves were born following vitrification and embryo transfer of these embryos; two from the PHA-treated group, and one from non-PHA control group. We concluded that PHA treatment significantly improved the fusion efficiency of somatic NT in cattle, and therefore, increased the development of cloned blastocysts. Furthermore, within a determined range of dose and duration, PHA had no detrimental effect on embryo survival post-vitrification, nor on pregnancy or calving rates following embryo transfer.

  18. Single TCR-Vβ2 evaluation discloses the circulating T cell clone in Sezary syndrome: one family fits all!

    Science.gov (United States)

    Scala, Enrico; Abeni, Damiano; Pomponi, Debora; Russo, Nicoletta; Russo, Giandomenico; Narducci, Maria Grazia

    2015-08-01

    Sézary Syndrome (SS/L-CTCL) is a rare but aggressive variant of cutaneous T cell lymphoma (CTCL), characterized by erythroderma, lymphadenopathy, and the presence of a circulating memory CD4(+) T cell malignant clone with a skin homing behavior, lacking CD26 and CD49d and over-expressing CD60. The availability of a panel of monoclonal antibodies recognizing distinct TCR-Vβ families, allows to typify the clone by flow cytometry in about 70 % of cases. The TCR-Vβ repertoire of 533 individuals, comprising 308 patients affected by CTCL, 50 healthy donors, and subjects affected by various non-neoplastic dermatological affections was evaluated by flow cytometry. Statistical analyses were performed using the SPSS statistical software package for Microsoft Windows (SPSS, version 21, Chicago, IL). TCR-Vβ2 levels below 5.4 % or above 39.5 %, within total CD4(+) T cells, showed the best balance between sensitivity (98.1 %) and specificity (96 %) to identify the presence of a clone in the peripheral blood of patients affected by SS. Based on this observation, a "two-step" procedure in the detection of the malignant T cell clone in CTCLs is herein suggested. TCR-Vβ2 assessment in all cases (first step). In the case of TCR-Vβ2 levels above 39.5 %, the presence of a clonal expansion of this family is suggested, deserving further confirmation by means of T cell gene rearrangement evaluation. In patients having a TCR-Vβ2 reactivity below 5.4 % (second step), the entire TCR-Vβ repertoire should be evaluated to typify the expanded clone. In conclusion, the single TCR-Vβ2 expression check, instead of the entire repertoire assessment, represents an easy and cost-effective method for the recognition of CTCL aggressive leukemic variant.

  19. Isolation and cross-sensitivity of X-ray-sensitive mutants of V79-4 hamster cells

    International Nuclear Information System (INIS)

    Jones, N.J.; Cox, R.; Thacker, J.

    1987-01-01

    The V79-4 Chinese hamster line was mutagenized and surviving clones screened for X-ray sensitivity using a replica microwell technique. One slightly sensitive clone and 3 clearly sensitive clones were isolated from approximately 5000 screened, and designated irs 1 to irs 4. The 3 more sensitive clones showed different responses to the genotoxic agents mitomycin C (MMC), ethyl methanesulphonate (EMS) and ultraviolet light (UV). irs 1 showed considerable sensitivity to all the agents tested, in the order MMC >> EMS > UV. irs 2 and irs 3 had similar sensitivities to EMS and to UV (EMS > UV) but irs 3 was more sensitive than irs 2 to MMC. None of these mutants is identical in phenotype to previously published mutants. (Auth.)

  20. High level of surface CD4 prevents stable human immunodeficiency virus infection of T-cell transfectants.

    OpenAIRE

    Marshall, W L; Diamond, D C; Kowalski, M M; Finberg, R W

    1992-01-01

    CD4 is the principal receptor for the human immunodeficiency virus (HIV). We have isolated and studied CD4-expressing tumor cell clones made by expressing CD4 in the T-cell tumor line HSB. Two clones, one designated HSBCD4, a clone expressing low levels of CD4, and the other, HSB10xCD4, a high-expresser CD4+ clone, were studied for their ability to bind and replicate HIV. In contrast to many other CD4+ cells that down-modulate CD4 following HIV infection, the HSB10xCD4 clones continued to exp...

  1. The production of lymphokines by primary alloreactive T-cell clones: a co-ordinate analysis of 233 clones in seven lymphokine assays.

    Science.gov (United States)

    Sanderson, C J; Strath, M; Warren, D J; O'Garra, A; Kirkwood, T B

    1985-01-01

    A total of 233 primary alloreactive T-cell clones have been tested for the production of interleukin-2 (IL-2), interleukin-3 (IL-3), immune(gamma) interferon (IFN) and granulocyte-macrophage colony-stimulating factor (CSF-2), B-cell growth factor I and II (BCGFI, BCGFII), and eosinophil differentiation factor (EDF). EDF was assayed by means of the eosinophil differentiation assay (EDA). Two principal correlations were observed: IL-3 was shown to be the major lymphokine detected in the bone marrow proliferation assay (BMPA) used to detect CSF-2, and there was a high correlation between the EDA and BCGFII. Subsequent work has suggested that this latter correlation is because a single factor is responsible for both activities. Apart from these two exceptions, and low level correlations probably due to the fact that different assays detect more than one lymphokine, there was no evidence for co-ordinate expression of lymphokines. There was a large variation in amounts of individual lymphokines produced. More clones produced multiple lymphokines than would be expected from independent control. Taken together, this pattern of regulation is consistent with the hypothesis that antigen stimulation of T cells results in the activation of all the lymphokine genes, but the amount of each produced is determined by secondary controlling mechanisms. PMID:3935571

  2. Geotemporal analysis of Neisseria meningitidis clones in the United States: 2000-2005.

    Directory of Open Access Journals (Sweden)

    Ann E Wiringa

    Full Text Available The detection of meningococcal outbreaks relies on serogrouping and epidemiologic definitions. Advances in molecular epidemiology have improved the ability to distinguish unique Neisseria meningitidis strains, enabling the classification of isolates into clones. Around 98% of meningococcal cases in the United States are believed to be sporadic.Meningococcal isolates from 9 Active Bacterial Core surveillance sites throughout the United States from 2000 through 2005 were classified according to serogroup, multilocus sequence typing, and outer membrane protein (porA, porB, and fetA genotyping. Clones were defined as isolates that were indistinguishable according to this characterization. Case data were aggregated to the census tract level and all non-singleton clones were assessed for non-random spatial and temporal clustering using retrospective space-time analyses with a discrete Poisson probability model.Among 1,062 geocoded cases with available isolates, 438 unique clones were identified, 78 of which had ≥2 isolates. 702 cases were attributable to non-singleton clones, accounting for 66.0% of all geocoded cases. 32 statistically significant clusters comprised of 107 cases (10.1% of all geocoded cases were identified. Clusters had the following attributes: included 2 to 11 cases; 1 day to 33 months duration; radius of 0 to 61.7 km; and attack rate of 0.7 to 57.8 cases per 100,000 population. Serogroups represented among the clusters were: B (n = 12 clusters, 45 cases, C (n = 11 clusters, 27 cases, and Y (n = 9 clusters, 35 cases; 20 clusters (62.5% were caused by serogroups represented in meningococcal vaccines that are commercially available in the United States.Around 10% of meningococcal disease cases in the U.S. could be assigned to a geotemporal cluster. Molecular characterization of isolates, combined with geotemporal analysis, is a useful tool for understanding the spread of virulent meningococcal clones and patterns of

  3. Distinct forms of the β subunit of GTP-binding regulatory proteins identified by molecular cloning

    International Nuclear Information System (INIS)

    Fong, H.K.W.; Amatruda, T.T. III; Birren, B.W.; Simon, M.I.

    1987-01-01

    Two distinct β subunits of guanine nucleotide-binding regulatory proteins have been identified by cDNA cloning and are referred to as β 1 and β 1 subunits. The bovine transducin β subunit (β 1 ) has been cloned previously. The author now isolated and analyzed cDNA clones that encode the β 2 subunit from bovine adrenal, bovine brain, and a human myeloid leukemia cell line, HL-60. The 340-residue M/sub r/ 37,329 Β 2 protein is 90% identical with β 1 in predicted amino acid sequence, and it is also organized as a series of repetitive homologous segments. The major mRNA that encodes the bovine β 2 subunit is 1.7 kilobases in length. It is expressed at lower levels than β 1 subunit mRNA in all tissues examined. The β 1 and β 2 messages are expressed in cloned human cell lines. Hybridization of cDNA probes to bovine DNA showed that β 1 and β 2 are encoded by separate genes. The amino acid sequences for the bovine and human β 2 subunit are identical, as are the amino acid sequences for the bovine and human β 1 subunit. This evolutionary conservation suggests that the two β subunits have different roles in the signal transduction process

  4. Radiation-induced apoptosis in sensitive and resistant cells isolated from a mouse lymphoma

    International Nuclear Information System (INIS)

    Story, M.D.; Voehringer, D.W.; Malone, C.G.; Hobbs, M.L.; Meyn, R.E.

    1994-01-01

    Cells were isolated from a mouse lymphoma (LY-TH) and grown in vitro. They were susceptible to radiation-induced apoptosis after low doses with the appearance of endonucleolytically fragmented DNA 1 h after irradiation. Four hours after receiving 5 Gy, 80% of the DNA was endonucleolytically cleaved. Apoptosis induction by DNA double-strand break (dsb) formation was more effective compared with induction by single-strand break (ssb) formation. After long-term culturing, LY-TH cultures became refractory to apoptosis. Apoptosis-permissive cells (LY-as, cloned from LY-TH cells) were three times more radiosensitive than clonally expanded apoptosis-refractory cells (LY-ar). Low dose-rate irradiation and maintenance at 25 o C for 5 h postirradiation was sparing in LY-ar but not LY-as cells, suggesting a repair deficiency in LY-as cells. Analysis of dsb rejoining kinetics revealed no difference in the initial phase of dsb rejoining. After 1 h, however, relative dsbs in the LY-as variant increased as endonucleolytic cleavage was initiated. Signalling for radiation-induced apoptosis in LY-as cells was independent of the DNA dsb repair pathway and appeared determined by initial events, whereas in LY-ar cells, because of an inhibition in the apoptotic pathway, survival was enhanced and modifiable by repair processes. (author)

  5. Therapeutic and reproductive cloning: a critique.

    Science.gov (United States)

    Bowring, Finn

    2004-01-01

    This article is a critical examination of the science and ethics of human cloning. It summarises the key scientific milestones in the development of nuclear transplantation, explains the importance of cloning to research into the medical potential of embryonic stem cells, and discusses the well-worn distinction between 'therapeutic' and 'reproductive' cloning. Suggesting that this distinction will be impossible to police, it goes on to consider the ethics of full human cloning. It is concluded that it represents an unacceptable form of parental despotism, and that the genetic engineering and cloning of future human beings will fracture the foundations of modern humanism.

  6. Isolation of a primate embryonic stem cell line.

    OpenAIRE

    Thomson, J A; Kalishman, J; Golos, T G; Durning, M; Harris, C P; Becker, R A; Hearn, J P

    1995-01-01

    Embryonic stem cells have the ability to remain undifferentiated and proliferate indefinitely in vitro while maintaining the potential to differentiate into derivatives of all three embryonic germ layers. Here we report the derivation of a cloned cell line (R278.5) from a rhesus monkey blastocyst that remains undifferentiated in continuous passage for > 1 year, maintains a normal XY karyotype, and expresses the cell surface markers (alkaline phosphatase, stage-specific embryonic antigen 3, st...

  7. Sequence variation of functional HTLV-II tax alleles among isolates from an endemic population: lack of evidence for oncogenic determinant in tax.

    Science.gov (United States)

    Hjelle, B; Chaney, R

    1992-02-01

    Human T-cell leukemia-lymphoma virus type II (HTLV-II) has been isolated from patients with hairy cell leukemia (HCL). We previously described a population with longstanding endemic HTLV-II infection, and showed that there is no increased risk for HCL in the affected groups. We thus have direct evidence that the endemic form(s) of HTLV-II cause HCL infrequently, if at all. By comparison, there is reason to suspect that the viruses isolated from patients with HCL had an etiologic role in the disease in those patients. One way to reconcile these conflicting observations is to consider that isolates of HTLV-II might differ in oncogenic potential. To determine whether the structure of the putative oncogenic determinant of HTLV-II, tax2, might differ in the new isolates compared to the tax of the prototype HCL isolate, MO, four new functional tax cDNAs were cloned from new isolates. Sequence analysis showed only minor (0.9-2.0%) amino acid variation compared to the published sequence of MO tax2. Some codons were consistently different from published sequences of the MO virus, but in most cases, such variations were also found in each of two tax2 clones we isolated from the MO T-cell line. These variations rendered the new clones more similar to the tax1 of the pathogenic virus HTLV-I. Thus we find no evidence that pathologic determinants of HTLV-II can be assigned to the tax gene.

  8. cDNA cloning and immunological characterization of the rye grass allergen Lol p I.

    Science.gov (United States)

    Perez, M; Ishioka, G Y; Walker, L E; Chesnut, R W

    1990-09-25

    The complete amino acid sequence of two "isoallergenic" forms of Lol p I, the major rye grass (Lolium perenne) pollen allergen, was deduced from cDNA sequence analysis. cDNA clones isolated from a Lolium perenne pollen library contained an open reading frame coding for a 240-amino acid protein. Comparison of the nucleotide and deduced amino acid sequence of two of these clones revealed four changes at the amino acid level and numerous nucleotide differences. Both clones contained one possible asparagine-linked glycosylation site. Northern blot analysis shows one RNA species of 1.2 kilobases. Based on the complete amino acid sequence of Lol p I, overlapping peptides covering the entire molecule were synthesized. Utilizing these peptides we have identified a determinant within the Lol p I molecule that is recognized by human leukocyte antigen class II-restricted T cells obtained from persons allergic to rye grass pollen.

  9. Differential Regulation of Gene Expression of Alveolar Epithelial Cell Markers in Human Lung Adenocarcinoma-Derived A549 Clones

    Directory of Open Access Journals (Sweden)

    Hiroshi Kondo

    2015-01-01

    Full Text Available Stem cell therapy appears to be promising for restoring damaged or irreparable lung tissue. However, establishing a simple and reproducible protocol for preparing lung progenitor populations is difficult because the molecular basis for alveolar epithelial cell differentiation is not fully understood. We investigated an in vitro system to analyze the regulatory mechanisms of alveolus-specific gene expression using a human alveolar epithelial type II (ATII cell line, A549. After cloning A549 subpopulations, each clone was classified into five groups according to cell morphology and marker gene expression. Two clones (B7 and H12 were further analyzed. Under serum-free culture conditions, surfactant protein C (SPC, an ATII marker, was upregulated in both H12 and B7. Aquaporin 5 (AQP5, an ATI marker, was upregulated in H12 and significantly induced in B7. When the RAS/MAPK pathway was inhibited, SPC and thyroid transcription factor-1 (TTF-1 expression levels were enhanced. After treatment with dexamethasone (DEX, 8-bromoadenosine 3′5′-cyclic monophosphate (8-Br-cAMP, 3-isobutyl-1-methylxanthine (IBMX, and keratinocyte growth factor (KGF, surfactant protein B and TTF-1 expression levels were enhanced. We found that A549-derived clones have plasticity in gene expression of alveolar epithelial differentiation markers and could be useful in studying ATII maintenance and differentiation.

  10. Transcript levels of several epigenome regulatory genes in bovine somatic donor cells are not correlated with their cloning efficiency.

    Science.gov (United States)

    Zhou, Wenli; Sadeghieh, Sanaz; Abruzzese, Ronald; Uppada, Subhadra; Meredith, Justin; Ohlrichs, Charletta; Broek, Diane; Polejaeva, Irina

    2009-09-01

    Among many factors that potentially affect somatic cell nuclear transfer (SCNT) embryo development is the donor cell itself. Cloning potentials of somatic donor cells vary greatly, possibly because the cells have different capacities to be reprogrammed by ooplasma. It is therefore intriguing to identify factors that regulate the reprogrammability of somatic donor cells. Gene expression analysis is a widely used tool to investigate underlying mechanisms of various phenotypes. In this study, we conducted a retrospective analysis investigating whether donor cell lines with distinct cloning efficiencies express different levels of genes involved in epigenetic reprogramming including histone deacetylase-1 (HDAC1), -2 (HDAC2); DNA methyltransferase-1 (DNMT1), -3a (DNMT3a),-3b (DNMT3b), and the bovine homolog of yeast sucrose nonfermenting-2 (SNF2L), a SWI/SNF family of ATPases. Cell samples from 12 bovine donor cell lines were collected at the time of nuclear transfer experiments and expression levels of the genes were measured using quantitative polymerase chain reaction (PCR). Our results show that there are no significant differences in expression levels of these genes between donor cell lines of high and low cloning efficiency defined as live calving rates, although inverse correlations are observed between in vitro embryo developmental rates and expression levels of HDAC2 and SNF2L. We also show that selection of stable reference genes is important for relative quantification, and different batches of cells can have different gene expression patterns. In summary, we demonstrate that expression levels of these epigenome regulatory genes in bovine donor cells are not correlated with cloning potential. The experimental design and data analysis method reported here can be applied to study any genes expressed in donor cells.

  11. Radiation-induced aneusomic clones in bone marrow of rats

    International Nuclear Information System (INIS)

    Kohno, Sei-Ichi; Ishihara, Takaaki

    1976-01-01

    Wistar rats 3 months old were given a single whole-body X-irradiation with 700 R. They were killed 9.3 months, on average, after irradiation. From the bone marrows of the 23 irradiated rats, 54 clones of cells with radiation-induced chromosome abnormalities ranging from 3.3 to 78.3% in size were obtained. Karyotype analysis at the banding level showed that 43 out of the 54 clones had balanced chromosome constitutions and that the remaining 11 clones were unbalanced. The 43 balanced clones consisted of 33 clones with reciprocal translocations, 6 with inversions and 4 with both translocations and inversions. The 11 unbalanced clones were made up of 7 aneuploid clones and 4 pseudo-diploid clones. Of the 54 clones, 15 were large with frequencies of more than 25%. Contrary to general belief that cells with unbalanced chromosome constitutions have less capacity to proliferate than those with balanced ones, 8 of the 15 large clones, especially all, except 1, of the largest 6 clones were unbalanced, either aneuploid or pseudo-diploid

  12. Rabies virus-specific human T cell clones provide help for an in vitro antibody response against neutralizing antibody-inducing determinants of the viral glycoprotein.

    NARCIS (Netherlands)

    H. Bunschoten; R.J. Klapmuts; I.J.Th.M. Claassen (Ivo); S.D. Reijneveld; A.D.M.E. Osterhaus (Albert); F.G.C.M. Uytdehaag (Fons)

    1989-01-01

    textabstractHuman T cell clones were prepared from peripheral blood mononuclear cells from a vaccinated human donor and kept in culture in the presence of rabies virus antigen and growth factors. Phenotypic analysis of the T cell clones revealed expression of the CD3 and CD4 cell surface markers,

  13. Cloning and functional characterisation of avian transcription factor E2A

    Directory of Open Access Journals (Sweden)

    Meyer Kerstin B

    2004-06-01

    Full Text Available Abstract Background During B lymphocyte development the E2A gene is a critical regulator of cell proliferation and differentiation. With regards to the immunoglobulin genes the E2A proteins contribute to the regulation of gene rearrangement, expression and class switch recombination. We are now using the chicken cell line DT40 as a model system to further analyse the function of E2A. Results Here we report the cloning and functional analysis of the transcription factor E2A from chicken. Using RACE PCR on the chicken lymphoma cell line DT40 we have isolated full-length clones for the two E2A splice variants E12 and E47. Sequence conservation between the human and chicken proteins is extensive: the basic-helix-loop-helix DNA binding domain of human and chicken E47 and E12 are 93% and 92% identical, respectively. In addition high levels of conservation are seen in activation domain I, the potential NLS and the ubiquitin ligase interaction domain. E2A is expressed in a variety of tissues in chicken, with higher levels of expression in organs rich in immune cells. We demonstrate that chicken E12 and E47 proteins are strong transcriptional activators whose function depends on the presence of activation domain I. As in mammals, the dominant negative proteins Id1 and Id3 can inhibit the function of chicken E47. Conclusions The potential for homologous recombination in DT40 allows the genetic dissection of biochemical pathways in somatic cells. With the cloning of avian E2A and the recent description of an in vitro somatic hypermutation assay in this cell line, it should now be possible to dissect the potential role of E2A in the regulation of somatic hypermutation and gene conversion.

  14. Generation of an infectious clone of a new Korean isolate of apple chlorotic leaf spot virus (ACLSV) driven by dual 35S and T7 promoters in a versatile binary vector

    Science.gov (United States)

    The full-length sequence of a new isolate of Apple chlorotic leaf spot virus (ACLSV) from Korea was divergent, but most closely related to the Japanese isolate A4, at 84% nucleotide identity. The full-length cDNA of the Korean isolate of ACLSV was cloned into a binary vector downstream of the bacter...

  15. A protocol for adult somatic cell nuclear transfer in medaka fish (Oryzias latipes) with a high rate of viable clone formation.

    Science.gov (United States)

    Bubenshchikova, Ekaterina; Kaftanovskaya, Elena; Adachi, Tomoko; Hashimoto, Hisashi; Kinoshita, Masato; Wakamatsu, Yuko

    2013-12-01

    Previously, we successfully generated fully grown, cloned medaka (the Japanese rice fish, Oryzias latipes) using donor nuclei from primary culture cells of adult caudal fin tissue and nonenucleated recipient eggs that were heat shock-treated to induce diploidization of the nuclei. However, the mechanism of clone formation using this method is unknown, and the rate of adult clone formation is not high enough for studies in basic and applied sciences. To gain insight into the mechanism and increase the success rate of this method of clone formation, we tested two distinct nuclear transfer protocols. In one protocol, the timing of transfer of donor nuclei was changed, and in the other, the size of the donor cells was changed; each protocol was based on our original methodology. Ultimately, we obtained an unexpectedly high rate of adult clone formation using the protocol that differed with respect to the timing of donor nuclei transfer. Specifically, 17% of the transplants that developed to the blastula stage ultimately developed into adult clones. The success rate with this method was 13 times higher than that obtained using the original method. Analyses focusing on the reasons for this high success rate of clone formation will help to elucidate the mechanism of clone formation that occurs with this method.

  16. Primary structure of the α-subunit of Na+, K+-ATPase. II. Isolation, reverse transcription, and cloning of messenger RNA

    International Nuclear Information System (INIS)

    Petrukhin, K.E.; Broude, N.E.; Arsenyan, S.G.; Grishin, A.V.; Dzhandzhugazyan, K.N.; Modyanov, N.N.

    1986-01-01

    The messenger RNA coding the α-subunit of Na + ,K + -ATPase has been isolated from the outer medullary layer of porcine kidneys. The mRNA gives a specific hybridization band in the 25S-26S region with three oligonucleotide probes synthesized on the basis of information on the structure of three peptides isolated from a tryptic hydrolyzate of the α-subunit of Na + ,K + -ATPase. The translation of the mRNA in Xenopus laevis oocytes followed by immunochemical identification of the products of synthesis confirmed the presence of the mRNA of the α-subunit of Na + ,K + -ATPase in an enriched fraction of poly(A + )-RNA. This preparation has been used for the synthesis of cloning of double-stranded cDNA

  17. Cloning and expression of NS3 gene of Pakistani isolate type 2 dengue virus

    Directory of Open Access Journals (Sweden)

    Yasmin Farkhanda

    2018-03-01

    Full Text Available Introduction: Dengue is one of the major emerging viral diseases in the world, with dramatic increases in reported cases in the last few decades and annual worldwide occurrence of approximately 390 million infections. It is a highly important mosquito-vectored disease and is a problem in tropical and subtropical areas of the world. The major aim of this study was to clone and express the dengue NS3 gene, in service to its therapeutic importance for the development of stable cell lines.

  18. [Telomere lengthening by trichostatin A treatment in cloned pigs].

    Science.gov (United States)

    Xie, Bing-Teng; Ji, Guang-Zhen; Kong, Qing-Ran; Mao, Jian; Shi, Yong-Qian; Liu, Shi-Chao; Wu, Mei-Ling; Wang, Juan; Liu, Lin; Liu, Zhong-Hua

    2012-12-01

    Telomeres are repeated GC rich sequences at the end of chromosomes, and shorten with each cell division due to DNA end replication problem. Previously, reprogrammed somatic cells of cloned animals display variable telomere elongation. However, it was reported that the cloned animals including Dolly do not reset telomeres and show premature aging. In this study, we investigated telomere function in cloned or transgenic cloned pigs, including the cloned Northeast Min pigs, eGFP, Mx, and PGC1α transgenic cloned pigs, and found that the telomere lengths of cloned pigs were significantly shorter than the nuclear donor adult fibroblasts and age-matched noncloned pigs (Pstage for 24 h. Consistent with previous reports, the developmental rate of SCNT embryos to the blastocyst stage was significantly increased compared with those of the control group (16.35% vs. 27.09%, 21.60% vs. 34.90%, Plengthen the telomere lengths of cloned pigs.

  19. Cloning Expeditions: Risky but Rewarding

    Science.gov (United States)

    2013-01-01

    In the 1980s, a good part of my laboratory was using the then-new recombinant DNA techniques to clone and characterize many important cell surface membrane proteins: GLUT1 (the red cell glucose transporter) and then GLUT2 and GLUT4, the red cell anion exchange protein (Band 3), asialoglycoprotein receptor subunits, sucrase-isomaltase, the erythropoietin receptor, and two of the subunits of the transforming growth factor β (TGF-β) receptor. These cloned genes opened many new fields of basic research, including membrane insertion and trafficking of transmembrane proteins, signal transduction by many members of the cytokine and TGF-β families of receptors, and the cellular physiology of glucose and anion transport. They also led to many insights into the molecular biology of several cancers, hematopoietic disorders, and diabetes. This work was done by an exceptional group of postdocs and students who took exceptionally large risks in developing and using novel cloning technologies. Unsurprisingly, all have gone on to become leaders in the fields of molecular cell biology and molecular medicine. PMID:24061478

  20. Identification of potential nuclear reprogramming and differentiation factors by a novel selection method for cloning chromatin-binding proteins

    International Nuclear Information System (INIS)

    Wang Liu; Zheng Aihua; Yi Ling; Xu Chongren; Ding Mingxiao; Deng Hongkui

    2004-01-01

    Nuclear reprogramming is critical for animal cloning and stem cell creation through nuclear transfer, which requires extensive remodeling of chromosomal architecture involving dramatic changes in chromatin-binding proteins. To understand the mechanism of nuclear reprogramming, it is critical to identify chromatin-binding factors specify the reprogramming process. In this report, we have developed a high-throughput selection method, based on T7 phage display and chromatin immunoprecipitation, to isolate chromatin-binding factors expressed in mouse embryonic stem cells using primary mouse embryonic fibroblast chromatin. Seven chromatin-binding proteins have been isolated by this method. We have also isolated several chromatin-binding proteins involved in hepatocyte differentiation. Our method provides a powerful tool to rapidly and selectively identify chromatin-binding proteins. The method can be used to study epigenetic modification of chromatin during nuclear reprogramming, cell differentiation, and transdifferentiation

  1. Genetic changes in Mammalian cells transformed by helium cells

    Energy Technology Data Exchange (ETDEWEB)

    Durante, M.; Grossi, G. (Naples Univ. (Italy). Dipt. di Scienze Fisiche); Yang, T.C.; Roots, R. (Lawrence Berkeley Lab., CA (USA))

    1990-11-01

    Midterm Syrian Hamster embryo (SHE) cells were employed to study high LET-radiation induced tumorigenesis. Normal SHE cells (secondary passage) were irradiated with accelerated helium ions at an incident energy of 22 MeV/u (9--10 keV/{mu}m). Transformed clones were isolated after growth in soft agar of cells obtained from the foci of the initial monolayer plated postirradiation. To study the progression process of malignant transformation, the transformed clones were followed by monolayer subculturing for prolonged periods of time. Subsequently, neoplasia tests in nude mice were done. In this work, however, we have focused on karyotypic changes in the banding patterns of the chromosomes during the early part of the progressive process of cell transformation for helium ion-induced transformed cells. 26 refs., 5 figs., 2 tabs.

  2. Attempt at cloning high-quality goldfish breed 'Ranchu' by fin-cultured cell nuclear transplantation.

    Science.gov (United States)

    Tanaka, Daisuke; Takahashi, Akito; Takai, Akinori; Ohta, Hiromi; Ueno, Koichi

    2012-02-01

    The viability of ornamental fish culture relies on the maintenance of high-quality breeds. To improve the profitability of culture operations we attempted to produce cloned fish from the somatic nucleus of the high-quality Japanese goldfish (Carassius auratus auratus) breed 'Ranchu'. We transplanted the nucleus of a cultured fin-cell from an adult Ranchu into the non-enucleated egg of the original goldfish breed 'Wakin'. Of the 2323 eggs we treated, 802 underwent cleavage, 321 reached the blastula stage, and 51 reached the gastrula stage. Two of the gastrulas developed until the hatching stage. A considerable number of nuclear transplants retained only the donor nucleus. Some of these had only a 2n nucleus derived from the same donor fish. Our results provide insights into the process of somatic cell nuclear transplantation in teleosts, and the cloning of Ranchu.

  3. Should we clone human beings? Cloning as a source of tissue for transplantation.

    Science.gov (United States)

    Savulescu, J

    1999-01-01

    The most publicly justifiable application of human cloning, if there is one at all, is to provide self-compatible cells or tissues for medical use, especially transplantation. Some have argued that this raises no new ethical issues above those raised by any form of embryo experimentation. I argue that this research is less morally problematic than other embryo research. Indeed, it is not merely morally permissible but morally required that we employ cloning to produce embryos or fetuses for the sake of providing cells, tissues or even organs for therapy, followed by abortion of the embryo or fetus. PMID:10226910

  4. Consumers' attitudes toward consumption of cloned beef. The impact of exposure to technological information about animal cloning.

    Science.gov (United States)

    Aizaki, Hideo; Sawada, Manabu; Sato, Kazuo

    2011-10-01

    Novel food technologies, such as cloning, have been introduced into the meat production sector; however, their use is not widely supported by many consumers. This study was designed to assess whether Japanese consumers' attitudes toward consumption of cloned beef (specifically, beef derived from bovine embryo and somatic cell-cloned cattle) would change after they were provided with technological information on animal cloning through a web-based survey. The results revealed that most respondents did not discriminate between their attitudes toward the consumption of the two types of cloned beef, and that most respondents did not change their attitudes toward cloned beef after receiving the technological information. The respondents' individual characteristics, including their knowledge about the food safety of cloned beef and their basic knowledge about animal cloning, influenced the likelihood of a change in their attitudes after they received the information. In conclusion, some consumers might become less uncomfortable about the consumption of cloned beef by the straightforward provision of technological information about animal cloning; however, most consumers are likely to maintain their attitudes. Copyright © 2011 Elsevier Ltd. All rights reserved.

  5. Feedback regulation of methyl methanesulfonate and ultraviolet-sensitive gene clone 81 via ATM/Chk2 pathway contributes to the resistance of MCF-7 breast cancer cells to cisplatin.

    Science.gov (United States)

    Lv, Juan; Qian, Ying; Ni, Xiaoyan; Xu, Xiuping; Dong, Xuejun

    2017-03-01

    The methyl methanesulfonate and ultraviolet-sensitive gene clone 81 protein is a structure-specific nuclease that plays important roles in DNA replication and repair. Knockdown of methyl methanesulfonate and ultraviolet-sensitive gene clone 81 has been found to sensitize cancer cells to chemotherapy. However, the underlying molecular mechanism is not well understood. We found that methyl methanesulfonate and ultraviolet-sensitive gene clone 81 was upregulated and the ATM/Chk2 pathway was activated at the same time when MCF-7 cells were treated with cisplatin. By using lentivirus targeting methyl methanesulfonate and ultraviolet-sensitive gene clone 81 gene, we showed that knockdown of methyl methanesulfonate and ultraviolet-sensitive gene clone 81 enhanced cell apoptosis and inhibited cell proliferation in MCF-7 cells under cisplatin treatment. Abrogation of ATM/Chk2 pathway inhibited cell viability in MCF-7 cells in response to cisplatin. Importantly, we revealed that ATM/Chk2 was required for the upregulation of methyl methanesulfonate and ultraviolet-sensitive gene clone 81, and knockdown of methyl methanesulfonate and ultraviolet-sensitive gene clone 81 resulted in inactivation of ATM/Chk2 pathway in response to cisplatin. Meanwhile, knockdown of methyl methanesulfonate and ultraviolet-sensitive gene clone 81 activated the p53/Bcl-2 pathway in response to cisplatin. These data suggest that the ATM/Chk2 may promote the repair of DNA damage caused by cisplatin by sustaining methyl methanesulfonate and ultraviolet-sensitive gene clone 81, and the double-strand breaks generated by methyl methanesulfonate and ultraviolet-sensitive gene clone 81 may activate the ATM/Chk2 pathway in turn, which provide a novel mechanism of how methyl methanesulfonate and ultraviolet-sensitive gene clone 81 modulates DNA damage response and repair.

  6. Isolation and functional aspects of free luteal cells

    International Nuclear Information System (INIS)

    Luborsky, J.L.; Berhrman, H.R.

    1985-01-01

    Methods of luteal cell isolation employ enzymatic treatment of luteal tissue with collagenase and deoxyribonuclease. Additional enzymes such as hyaluronidase or Pronase are also used in some instances. Isolated luteal cells retain the morphological characteristics of steroid secreting cells after isolation. They contain mitochondria, variable amounts of lipid droplets, and an extensive smooth endoplasmic reticulum. Isolated luteal cells have been used in numerous studies to examine the regulation of steriodogenesis by luteinizing hormone (LH). LH receptor binding studies were employed to quantitate specific properties of hormone-receptor interaction in relation to cellular function. Binding of [ 125 I]LH to bovine luteal cells and membranes was compared and it was concluded that the enzymatic treatment used to isolate cells did not change the LH receptor binding kinetics

  7. Human somatic cell nuclear transfer and reproductive cloning: an Ethics Committee opinion.

    Science.gov (United States)

    2016-04-01

    This document presents arguments that conclude that it is unethical to use somatic cell nuclear transfer (SCNT) for infertility treatment due to concerns about safety; the unknown impact of SCNT on children, families, and society; and the availability of other ethically acceptable means of assisted reproduction. This document replaces the ASRM Ethics Committee report titled, "Human somatic cell nuclear transfer and cloning," last published in Fertil Steril 2012;98:804-7. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  8. Cloning of B cell-specific membrane tetraspanning molecule BTS possessing B cell proliferation-inhibitory function.

    Science.gov (United States)

    Suenaga, Tadahiro; Arase, Hisashi; Yamasaki, Sho; Kohno, Masayuki; Yokosuka, Tadashi; Takeuchi, Arata; Hattori, Takamichi; Saito, Takashi

    2007-11-01

    Lymphocyte proliferation is regulated by signals through antigen receptors, co-stimulatory receptors, and other positive and negative modulators. Several membrane tetraspanning molecules are also involved in the regulation of lymphocyte growth and death. We cloned a new B cell-specific tetraspanning (BTS) membrane molecule, which is similar to CD20 in terms of expression, structure and function. BTS is specifically expressed in the B cell line and its expression is increased after the pre-B cell stage. BTS is expressed in intracellular granules and on the cell surface. Overexpression of BTS in immature B cell lines induces growth retardation through inhibition of cell cycle progression and cell size increase without inducing apoptosis. This inhibitory function is mediated predominantly by the N terminus of BTS. The development of mature B cells is inhibited in transgenic mice expressing BTS, suggesting that BTS is involved in the in vivo regulation of B cells. These results indicate that BTS plays a role in the regulation of cell division and B cell growth.

  9. Histone deacetylase inhibitor significantly improved the cloning efficiency of porcine somatic cell nuclear transfer embryos.

    Science.gov (United States)

    Huang, Yongye; Tang, Xiaochun; Xie, Wanhua; Zhou, Yan; Li, Dong; Yao, Chaogang; Zhou, Yang; Zhu, Jianguo; Lai, Liangxue; Ouyang, Hongsheng; Pang, Daxin

    2011-12-01

    Valproic acid (VPA), a histone deacetylase inbibitor, has been shown to generate inducible pluripotent stem (iPS) cells from mouse and human fibroblasts with a significant higher efficiency. Because successful cloning by somatic cell nuclear transfer (SCNT) undergoes a full reprogramming process in which the epigenetic state of a differentiated donor nuclear is converted into an embryonic totipotent state, we speculated that VPA would be useful in promoting cloning efficiency. Therefore, in the present study, we examined whether VPA can promote the developmental competence of SCNT embryos by improving the reprogramming state of donor nucleus. Here we report that 1 mM VPA for 14 to 16 h following activation significantly increased the rate of blastocyst formation of porcine SCNT embryos constructed from Landrace fetal fibroblast cells compared to the control (31.8 vs. 11.4%). However, we found that the acetylation level of Histone H3 lysine 14 and Histone H4 lysine 5 and expression level of Oct4, Sox2, and Klf4 was not significantly changed between VPA-treated and -untreated groups at the blastocyst stage. The SCNT embryos were transferred to 38 surrogates, and the cloning efficiency in the treated group was significantly improved compared with the control group. Taken together, we have demonstrated that VPA can improve both in vitro and in vivo development competence of porcine SCNT embryos.

  10. Spread of carbapenem-resistant Acinetobacter baumannii global clone 2 in Asia and AbaR-type resistance islands.

    Science.gov (United States)

    Kim, Dae Hun; Choi, Ji-Young; Kim, Hae Won; Kim, So Hyun; Chung, Doo Ryeon; Peck, Kyong Ran; Thamlikitkul, Visanu; So, Thomas Man-Kit; Yasin, Rohani M D; Hsueh, Po-Ren; Carlos, Celia C; Hsu, Li Yang; Buntaran, Latre; Lalitha, M K; Song, Jae-Hoon; Ko, Kwan Soo

    2013-11-01

    In this surveillance study, we identified the genotypes, carbapenem resistance determinants, and structural variations of AbaR-type resistance islands among carbapenem-resistant Acinetobacter baumannii (CRAB) isolates from nine Asian locales. Clonal complex 92 (CC92), corresponding to global clone 2 (GC2), was the most prevalent in most Asian locales (83/108 isolates; 76.9%). CC108, or GC1, was a predominant clone in India. OXA-23 oxacillinase was detected in CRAB isolates from most Asian locales except Taiwan. blaOXA-24 was found in CRAB isolates from Taiwan. AbaR4-type resistance islands, which were divided into six subtypes, were identified in most CRAB isolates investigated. Five isolates from India, Malaysia, Singapore, and Hong Kong contained AbaR3-type resistance islands. Of these, three isolates harbored both AbaR3- and AbaR4-type resistance islands simultaneously. In this study, GC2 was revealed as a prevalent clone in most Asian locales, with the AbaR4-type resistance island predominant, with diverse variants. The significance of this study lies in identifying the spread of global clones of carbapenem-resistant A. baumannii in Asia.

  11. Cloning and over-expression of Penicillin G acylase in Escherichia ...

    African Journals Online (AJOL)

    The aim of this study is to screen for PGA producing Escherichia coli isolates as well as the cloning and recombinant expression of PGA for high level enzyme production. Bacteria isolated from environmental and clinical samples were identified by standard microbiological tests and then E. coli isolates were subjected to

  12. Molecular Cloning, Expression and Characterization of Plasmid Encoding Rhomboid 4 (ROM4 of Tachyzoite of Toxoplasma gondii RH Strain

    Directory of Open Access Journals (Sweden)

    Mohammad Taghi RAHIMI

    2017-12-01

    Full Text Available AbstractBackground: The objective of this study was to clone, express and characterize the gene encoding rhomboid 4 (ROM4 proteins, a vital gene in surface adhesion and host cell invasion process of tachyzoite of T. gondii in an appropriate expression vector and eukaryotic cell for production of recombinant protein.Methods: Toxoplasma RNA was isolated from tachyzoites (RH strain and complementary DNA was synthesized. Oligonucleotide primer pair was designed based on Toxoplasma ROM4 gene sequence with XhoI and EcoRI restriction sites at 5´ end of forward and reverse primers, respectively. ROM4 gene was amplified by PCR, cloned into pTG19-T vector and the recombinant plasmid was sequenced. The gene was subcloned into pcDNA3 plasmid and expressed in CHO cells as eukaryotic cell. SDS-PAGE and western blotting were performed for protein determination and verification.Results: Cloning of ROM4 gene in pTG19-T vector was confirmed by colony-PCR and enzymatic digestion. The results of enzymatic digestion and gene sequencing confirmed successful cloning and subcloning procedures. The nucleotide sequence of the cloned ROM4 gene showed 99% homology compared to the corresponding sequences of original gene. SDS-PAGE and western blotting analyses of the purified protein revealed a single band having expected size of 65 kDa.Conclusion: This eukaryotic expression system is an appropriate system for high-level recombinant protein production of ROM4 gene from T. gondii tachyzoites used as antigenic component for serological assay and vaccine development.

  13. Big Animal Cloning Using Transgenic Induced Pluripotent Stem Cells: A Case Study of Goat Transgenic Induced Pluripotent Stem Cells.

    Science.gov (United States)

    Song, Hui; Li, Hui; Huang, Mingrui; Xu, Dan; Wang, Ziyu; Wang, Feng

    2016-02-01

    Using of embryonic stem cells (ESCs) could improve production traits and disease resistance by improving the efficiency of somatic cell nuclear transfer (SCNT) technology. However, robust ESCs have not been established from domestic ungulates. In the present study, we generated goat induced pluripotent stem cells (giPSCs) and transgenic cloned dairy goat induced pluripotent stem cells (tgiPSCs) from dairy goat fibroblasts (gFs) and transgenic cloned dairy goat fibroblasts (tgFs), respectively, using lentiviruses that contained hOCT4, hSOX2, hMYC, and hKLF4 without chemical compounds. The giPSCs and tgiPSCs expressed endogenous pluripotent markers, including OCT4, SOX2, MYC, KLF4, and NANOG. Moreover, they were able to maintain a normal karyotype and differentiate into derivatives from all three germ layers in vitro and in vivo. Using SCNT, tgFs and tgiPSCs were used as donor cells to produce embryos, which were named tgF-Embryos and tgiPSC-Embryos. The fusion rates and cleavage rates had no significant differences between tgF-Embryos and tgiPSC-Embryos. However, the expression of IGF-2, which is an important gene associated with embryonic development, was significantly lower in tgiPSC-Embryos than in tgF-Embryos and was not significantly different from vivo-Embryos.

  14. Developmental fate of hematopoietic stem cells: the study of individual hematopoietic clones at the level of antigen-responsive B lymphocytes.

    Science.gov (United States)

    Olovnikova, Natalia I; Drize, Nina J; Ershler, Maxim A; Nifontova, Irina N; Belkina, Elena V; Nikolaeva, Tatiana N; Proskurina, Natalia V; Chertkov, Joseph L

    2003-01-01

    We have shown previously that hematopoiesis in mice reconstituted with retrovirally marked hematopoietic stem cells (HSCs) is provided by multiple, mainly short-lived clones, as measured by retroviral insertion site analysis of individual spleen colony-forming unit (CFU-S)-derived colonies. However, the CFU-S is the relatively early progenitor and the contribution of each CFU-S in the steady-state hematopoiesis is uncertain. Here, we have studied the fate of individual mature B cells, as well as CFU-S, representing the progeny of retrovirally transduced marrow-repopulating cells (MRC). B-cells-generated hybridomas and CFU-S-derived colonies were used to determine the clonal composition of hematolymphopoiesis at the single-cell level. Bone marrow (BM) cells and splenocytes (approximately 1/3-1/2 of spleen at a time) from mice reconstituted with retrovirally marked syngeneic BM cells were repeatedly collected at 3, 10, and 16 months post-transplant. The percentage of retrovirally marked CFU-S and B-cell-produced hybridomas was about 50% at 3 months and decreased to 10-15% at 10 months after reconstitution in spite of stable degree of chimerism. The clonal origin of BM-derived CFU-S and spleen-derived B-cell hybridomas was detected by Southern blot analysis. Overall, DNA obtained from 159 retrovirally marked spleen colonies, 287 hybridomas and 43 BM samples were studied. Multiple simultaneously functioning clones of MRC-derived B cells were observed. The same individual clones among hybridomas and CFU-S were identified in three out of 11 mice. Thus, hematopoiesis is generated by multiple hematopoietic clones some of which can simultaneously contribute to both mature lymphoid cells and myeloid progenitors. These data establish that the stem cell compartment functions by continuously producing progeny, which fully but transiently repopulate all lineages.

  15. Reliable cloning of functional antibody variable domains from hybridomas and spleen cell repertoires employing a reengineered phage display system.

    Science.gov (United States)

    Krebber, A; Bornhauser, S; Burmester, J; Honegger, A; Willuda, J; Bosshard, H R; Plückthun, A

    1997-02-14

    A prerequisite for the use of recombinant antibody technologies starting from hybridomas or immune repertoires is the reliable cloning of functional immunoglobulin genes. For this purpose, a standard phage display system was optimized for robustness, vector stability, tight control of scFv-delta geneIII expression, primer usage for PCR amplification of variable region genes, scFv assembly strategy and subsequent directional cloning using a single rare cutting restriction enzyme. This integrated cloning, screening and selection system allowed us to rapidly obtain antigen binding scFvs derived from spleen-cell repertoires of mice immunized with ampicillin as well as from all hybridoma cell lines tested to date. As representative examples, cloning of monoclonal antibodies against a his tag, leucine zippers, the tumor marker EGP-2 and the insecticide DDT is presented. Several hybridomas whose genes could not be cloned in previous experimental setups, but were successfully obtained with the present system, expressed high amounts of aberrant heavy and light chain mRNAs, which were amplified by PCR and greatly exceeded the amount of binding antibody sequences. These contaminating variable region genes were successfully eliminated by employing the optimized phage display system, thus avoiding time consuming sequencing of non-binding scFv genes. To maximize soluble expression of functional scFvs subsequent to cloning, a compatible vector series to simplify modification, detection, multimerization and rapid purification of recombinant antibody fragments was constructed.

  16. Leishmania donovani-reactive Th1- and Th2-like T-cell clones from individuals who have recovered from visceral leishmaniasis

    DEFF Research Database (Denmark)

    Kemp, M; Kurtzhals, J A; Bendtzen, K

    1993-01-01

    analyzed in a panel of L. donovani-reactive CD4+ human T-cell clones generated from individuals who had recovered from VL after antimonial treatment. Two of the T-cell clones produced large amounts of IL-4 without production of IFN-gamma, seven clones produced both IFN-gamma and IL-4, and eight produced...... by interleukin-4 (IL-4)-producing Th2 cells, or cure may result by Th1 cells secreting gamma interferon (IFN-gamma). The present study examined the potential of human T cells to generate Th1 or Th2 responses to L. donovani. The profiles of IFN-gamma, IL-4, and lymphotoxin secretion after antigen stimulation were...... only IFN-gamma. This is the first report of a Th1- and Th2-type response in human leishmaniasis. These results suggest that in analogy with murine models, there is a dichotomy in the human T-cell response to L. donovani infections. Preferential activation of IL-4-producing Th2-like cells may...

  17. Piglets born from handmade cloning, an innovative cloning method without micromanipulation

    DEFF Research Database (Denmark)

    Du, Y.; Kragh, P.M.; Zhang, Y.

    2007-01-01

    Porcine handmade cloning (HMC), a simplified alternative of micromanipulation based traditional cloning (TC) has been developed in multiple phases during the past years, but the final evidence of its biological value, births of piglets was missing. Here we report the first births of healthy piglets......) of HMC reconstructed embryos developed to blastocysts with an average cell number of 77 ± 3 (n = 26) after 7 days in vitro culture (IVC). According to our knowledge, this is the highest in vitro developmental rate after porcine somatic cell nuclear transfer (SCNT). A total of 416 blastocysts from HMC......, mixed with 150 blastocysts from TC using a cell line from a different breed were transferred surgically to nine synchronized recipients. Out of the four pregnancies (44.4%) two were lost, while two pregnancies went to term and litters of 3 and 10 piglets were delivered by Caesarean section, with live...

  18. Grazing-Activated Production of Dimethyl Sulfide (DMS) by two clones of Emiliania huxleyi

    Science.gov (United States)

    Wolfe, Gordon V.; Steinke, Michael

    1996-01-01

    Emiliania huxleyi clones CCMP 370 and CCMP 373 produced similar amounts of dimethylsulfoniopropionate (DMSP) during axenic exponential growth, averaging 109 mM internal DMSP. Both clones had detectable DMSP lyase activity, as measured by production of dimethyl sulfide (DMS) during in vitro assays of crude cell preparations, but activities and conditions differed considerably between clones. Clone 373 had high activity; clone 370 had low activity and required chloride. For both strains, enzyme activity per cell was constant during exponential growth, but little DMS was produced by healthy cells. Rather, DMS production was activated when cells were subjected to physical or chemical stresses that caused cell lysis. We propose that DMSP lyase and DMSP are segregated within these cells and re-action only under conditions that result in cell stress or damage. Such activation occurs during microzooplankton grazing. When these clones were grazed by the dinoflagellate Oxyrrhis marina, DMS was produced; ungrazed cells, as well as those exposed to grazer exudates and associated bacteria, generated no DMS. Grazing of clone 373 produced much more DMS than grazing of clone 370, consistent with their relative in vitro DMSP lyase activities. DMS was only generated when cells were actually being grazed, indicating that ingested cells were responsible for the DMS formation. We suggest that even low levels of grazing can greatly accelerate DMS production.

  19. [TSA improve transgenic porcine cloned embryo development and transgene expression].

    Science.gov (United States)

    Kong, Qing-Ran; Zhu, Jiang; Huang, Bo; Huan, Yan-Jun; Wang, Feng; Shi, Yong-Qian; Liu, Zhong-Feng; Wu, Mei-Ling; Liu, Zhong-Hua

    2011-07-01

    Uncompleted epigenetic reprogramming is attributed to the low efficiency of producing transgenic cloned animals. Histone modification associated with epigenetics can directly influence the embryo development and transgene expression. Trichostatin A (TSA), as an inhibitor of histone deacetylase, can change the status of histone acetylation, improve somatic cell reprogramming, and enhance cloning efficiency. TSA prevents the chromatin structure from being condensed, so that transcription factor could binds to DNA sequence easily and enhance transgene expression. Our study established the optimal TSA treatment on porcine donor cells and cloned embryos, 250 nmol/L, 24 h and 40 nmol/L, 24 h, respectively. Furthermore, we found that both the cloned embryo and the donor cell treated by TSA resulted in the highest development efficiency. Meanwhile, TSA can improve transgene expression in donor cell and cloned embryo. In summary, TSA can significantly improve porcine reconstructed embryo development and transgene expression.

  20. Quantitative discrimination of Aggregatibacter actinomycetemcomitans highly leukotoxic JP2 clone from non-JP2 clones in diagnosis of aggressive periodontitis.

    Science.gov (United States)

    Yoshida, Akihiro; Ennibi, Oum-Keltoum; Miyazaki, Hideo; Hoshino, Tomonori; Hayashida, Hideaki; Nishihara, Tatsuji; Awano, Shuji; Ansai, Toshihiro

    2012-10-11

    Aggregatibacter actinomycetemcomitans is the etiological agent of periodontitis, and there is a strong association between clone JP2 and aggressive periodontitis in adolescents of African descent. The JP2 clone has an approximately 530-bp deletion (∆530) in the promoter region of the lkt/ltx gene, which encodes leukotoxin, and this clone has high leukotoxic activity. Therefore, this clone is very important in aggressive periodontitis. To diagnose this disease, culture methods and conventional PCR techniques are used. However, quantitative detection based on qPCR for the JP2 clone has not been developed due to genetic difficulties. In this study, we developed a qPCR-based quantification method specific to the JP2 clone. Based on our analysis of the DNA sequence of the lkt/ltx gene and its flanking region, we designed a reverse primer specific for the ∆530 deletion border sequence and developed a JP2-specific PCR-based quantification method using this primer. We also analyzed the DNA sequence of the ∆530 locus and found it to be highly conserved (97-100%) among 17 non-JP2 strains. Using the ∆530 locus, we designed a qPCR primer-probe set specific to non-JP2 clones. Next, we determined the numbers of JP2 and non-JP2 clone cells in the periodontal pockets of patients with aggressive periodontitis. The JP2-specific primers specifically amplified the genomic DNA of the A. actinomycetemcomitans JP2 clone and did not react with other bacterial DNA, whereas the non-JP2 specific primers reacted only with A. actinomycetemcomitans non-JP2 clones. Samples from the 88 periodontal sites in the 11 patients with aggressive periodontitis were analyzed. The bacterial cell numbers in 88 periodontal sites ranged from 0 to 4.8 × 10(8) (mean 1.28 × 10(7)) for JP2 clones and from 0 to 1.6 × 10(6) for non-JP2 clones (mean 1.84 × 10(5)). There were significant differences in the JP2 cell number between a clinical attachment level (CAL) ≤6 mm and a level ≥7 mm (p clones. This

  1. BIX-01294 increases pig cloning efficiency by improving epigenetic reprogramming of somatic cell nuclei.

    Science.gov (United States)

    Huang, Jiaojiao; Zhang, Hongyong; Yao, Jing; Qin, Guosong; Wang, Feng; Wang, Xianlong; Luo, Ailing; Zheng, Qiantao; Cao, Chunwei; Zhao, Jianguo

    2016-01-01

    Accumulating evidence suggests that faulty epigenetic reprogramming leads to the abnormal development of cloned embryos and results in the low success rates observed in all mammals produced through somatic cell nuclear transfer (SCNT). The aberrant methylation status of H3K9me and H3K9me2 has been reported in cloned mouse embryos. To explore the role of H3K9me2 and H3K9me in the porcine somatic cell nuclear reprogramming, BIX-01294, known as a specific inhibitor of G9A (histone-lysine methyltransferase of H3K9), was used to treat the nuclear-transferred (NT) oocytes for 14-16 h after activation. The results showed that the developmental competence of porcine SCNT embryos was significantly enhanced both in vitro (blastocyst rate 16.4% vs 23.2%, Pcloning rate 1.59% vs 2.96%) after 50 nm BIX-01294 treatment. BIX-01294 treatment significantly decreased the levels of H3K9me2 and H3K9me at the 2- and 4-cell stages, which are associated with embryo genetic activation, and increased the transcriptional expression of the pluripotency genes SOX2, NANOG and OCT4 in cloned blastocysts. Furthermore, the histone acetylation levels of H3K9, H4K8 and H4K12 in cloned embryos were decreased after BIX-01294 treatment. However, co-treatment of activated NT oocytes with BIX-01294 and Scriptaid rescued donor nuclear chromatin from decreased histone acetylation of H4K8 that resulted from exposure to BIX-01294 only and consequently improved the preimplantation development of SCNT embryos (blastocyst formation rates of 23.7% vs 21.5%). These results indicated that treatment with BIX-01294 enhanced the developmental competence of porcine SCNT embryos through improvements in epigenetic reprogramming and gene expression. © 2016 Society for Reproduction and Fertility.

  2. Emergence of Serratia marcescens isolates possessing carbapenem-hydrolysing β-lactamase KPC-2 from China.

    Science.gov (United States)

    Lin, X; Hu, Q; Zhang, R; Hu, Y; Xu, X; Lv, H

    2016-09-01

    Eighty-three carbapenem-resistant Serratia marcescens isolates were recovered from Zhejiang Provincial People's Hospital, China. The minimum inhibitory concentrations of imipenem, meropenem, and ertapenem for all isolates were 2 to >128 μg/mL. Polymerase chain reaction indicated that 63 S. marcescens isolates produced Klebsiella pneumoniae carbapenemase (KPC)-2. Clone A (15 isolates) and clone B (41 isolates) were the two dominant clones and clone A strains were gradually replaced by clone B strains between 2011 and 2014. The results indicate that blaKPC-2-positive S. marcescens emerged in our hospital as the major mechanism of carbapenem resistance. Copyright © 2016 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  3. Development of high-throughput phenotyping of metagenomic clones from the human gut microbiome for modulation of eukaryotic cell growth.

    Science.gov (United States)

    Gloux, Karine; Leclerc, Marion; Iliozer, Harout; L'Haridon, René; Manichanh, Chaysavanh; Corthier, Gérard; Nalin, Renaud; Blottière, Hervé M; Doré, Joël

    2007-06-01

    Metagenomic libraries derived from human intestinal microbiota (20,725 clones) were screened for epithelial cell growth modulation. Modulatory clones belonging to the four phyla represented among the metagenomic libraries were identified (hit rate, 0.04 to 8.7% depending on the screening cutoff). Several candidate loci were identified by transposon mutagenesis and subcloning.

  4. Suppression induction in vivo by a T helper clone?

    DEFF Research Database (Denmark)

    Crispe, I N; Owens, T

    1985-01-01

    We have previously described a helper T cell clone which augments in vivo cytotoxic T cell responses when injected at 10(4) cells per mouse, but not at 10(5) per mouse (Crispe, I. N. et al., Immunology 1984. 52:55). To test whether this dose-response relationship was due to the induction...... of suppression, naive syngeneic mice were injected with 10(5) cloned T helper cells, and their spleen cells were subsequently assayed for suppressive activity in adoptive transfer experiments. Lymphocytes from such mice indeed suppressed an antigen-specific cytotoxic response, but only in the presence...... of the same T helper cell clone freshly added at the time of adoptive transfer. On this basis we argue that the distinction between T helper cell activity and T suppressor-inducer activity corresponds to differences in cell numbers, rather than to two separate cell lineages....

  5. Generation and functional analysis of T cell lines and clones specific for schistosomula released products (SRP-A).

    Science.gov (United States)

    Damonneville, M; Velge, F; Verwaerde, C; Pestel, J; Auriault, C; Capron, A

    1987-08-01

    Antigens present in the products released by the larval stage of schistosome (SRP-A) were shown to induce a strong cytotoxic and protective IgE response both in the rat and the monkey. T cell lines and clones specific for SRP-A or 26 kD antigens which are the main target of the cytotoxic IgE have been derived. The passive transfer of SRP-A specific T lymphocytes into infected rats led to an increase of the IgE response, conferring a significant level of protection to the rats. In coculture assays in vitro, these cell lines significantly enhanced the production of IgE by SRP-A sensitized rat spleen cells. This helper effect on the IgE response was confirmed with 26 kD T cell clone supernatants. Moreover, supernatants obtained after stimulation with phorbol myristate acetate were able to enhance the IgE production of a hybridoma B cell line (B48-14) producing a monoclonal IgE antibody, cytotoxic for the schistosomula.

  6. Isolation of a cDNA for a Growth Factor of Vascular Endothelial Cells from Human Lung Cancer Cells: Its Identity with Insulin‐like Growth Factor II

    Science.gov (United States)

    Hagiwara, Koichi; Kobayashi, Tatsuo; Tobita, Masato; Kikyo, Nobuaki; Yazaki, Yoshio

    1995-01-01

    We have found growth‐promoting activity for vascular endothelial cells in the conditioned medium of a human lung cancer cell line, T3M‐11. Purification and characterization of the growth‐promoting activity have been carried out using ammonium sulfate precipitation and gel‐exclusion chromatography. The activity migrated as a single peak just after ribonuclease. It did not bind to a heparin affinity column. These results suggest that the activity is not a heparin‐binding growth factor (including fibroblast growth factors) or a vascular endothelial growth factor. To identify the molecule exhibiting the growth‐promoting activity, a cDNA encoding the growth factor was isolated through functional expression cloning in COS‐1 cells from a cDNA library prepared from T3M‐11 cells. The nucleotide sequence encoded by the cDNA proved to be identical with that of insulin‐like growth factor II. PMID:7730145

  7. Cloning of araA Gene Encoding L-Arabinose Isomerase from Marine Geobacillus stearothermophilus Isolated from Tanjung Api, Poso, Indonesia

    Directory of Open Access Journals (Sweden)

    DEWI FITRIANI

    2010-06-01

    Full Text Available L-arabinose isomerase is an enzyme converting D-galactose to D-tagatose. D-tagatose is a potential sweetener-sucrose substitute which has low calorie. This research was to clone and sequence araA gene from marine bacterial strain Geobacillus stearothermophilus isolated from Tanjung Api Poso Indonesia. The amplified araA gene consisted of 1494 bp nucleotides encoding 497 amino acids. DNA alignment analysis showed that the gene had high homology with that of G. stearothermophilus T6. The enzyme had optimum activity at high temperature and alkalin condition.

  8. [Out of natural order: nature in discourses about cloning and stem cell research in Brazilian newspapers].

    Science.gov (United States)

    Medeiros, Flavia Natércia da Silva

    2013-11-30

    Different conceptions of nature influence media coverage and public opinion about biotechnology. This study reports on a discourse analysis of the ideas about nature and what is natural expressed in Brazilian media coverage of cloning and stem cell research. In the discourse against this research, the biotechnologies in question are placed outside the natural order of things and deemed immoral. In the discourse of those who defend it, nature is portrayed as indifferent to the fate of humans or even cruel, or else a barrier to be overcome, while cloning and embryonic stem cells are naturalized and Dolly the sheep is anthropomorphized. The mythifying or transcendental representations of nature do not just influence public opinion, but also have ethical and political implications.

  9. Molecular Cloning and Function of FAS/APO1 Associated Protein in Breast Cancer.

    Science.gov (United States)

    1996-06-01

    Ariyama T, Abe T, Druck T, Ohta M, Huebner K, Yanagisawa J, Reed JC, Sato T: PTPN13, a Fas-associated protein tyrosine phosphatase, is located on...20. Yang, Q., and Tonks, N. K. (1991). Isolation of a cDNA clone encoding a human protein-tyrosine phosphatase with homology 7. Huebner, K., Druck , T...Acad. Sci. U.S.A. 91, 7477 (1994). Res. 53, 1945 (1993).(Fig. 3D ). In contrast to Jurkat cells which 13. The original description of PTP-BAS (12

  10. Clonal profile, virulence and resistance of Staphylococcus aureus isolated from sheep milk.

    Science.gov (United States)

    Martins, Katheryne Benini; Faccioli-Martins, Patricia Yoshida; Riboli, Danilo Flávio Moraes; Pereira, Valéria Cataneli; Fernandes, Simone; Oliveira, Aline A; Dantas, Ariane; Zafalon, Luiz Francisco; da Cunha, Maria de Lourdes Ribeiro de Souza

    2015-06-01

    The objective of this study was to characterize the clonal profile, virulence factors and antimicrobial resistance, particularly oxacillin resistance, of Staphylococcus aureus isolated from sheep milk. Milk samples were collected from all teats for the California Mastitis Test (CMT), somatic cell count, identification of S. aureus, investigation in these strains of genes encoding toxins (sea, seb, sec, sed, tst), biofilm (icaA, icaC, icaD, bap), leukocidin (luk-PV) oxacillin resistance by mecA gene detection and susceptibility testing (12 antibiotics). Messenger RNA expression was evaluated by RT-PCR in isolates carrying toxin and biofilm genes. Biofilm formation was also evaluated phenotypically by adherence to polystyrene plates. The clonal profile of S. aureus was investigated by pulsed-field gel electrophoresis. A total of 473 milk samples were collected from 242 animals on three farms and 20 S. aureus strains were isolated and none carried the mecA gene. The two sec gene-positive isolates and the isolates carrying the tst and luk-PV genes were positive by RT-PCR. Staphylococcus aureus isolated from the three flocks studied showed high susceptibility to the drugs tested and none was biofilm producer, indicating that biofilm formation was not a virulence factor causing infection by these strains. The typing of 17 S. aureus isolates revealed the presence of a common clone on the three farms studied, and the presence and expression of the sec and tst genes in one strain of this clone suggest the possible acquisition of virulence genes by this clone, a fact that is important for animal health and food hygiene.

  11. Clonal profile, virulence and resistance of Staphylococcus aureus isolated from sheep milk

    Science.gov (United States)

    Martins, Katheryne Benini; Faccioli-Martins, Patricia Yoshida; Riboli, Danilo Flávio Moraes; Pereira, Valéria Cataneli; Fernandes, Simone; Oliveira, Aline A.; Dantas, Ariane; Zafalon, Luiz Francisco; da Cunha, Maria de Lourdes Ribeiro de Souza

    2015-01-01

    The objective of this study was to characterize the clonal profile, virulence factors and antimicrobial resistance, particularly oxacillin resistance, of Staphylococcus aureus isolated from sheep milk. Milk samples were collected from all teats for the California Mastitis Test (CMT), somatic cell count, identification of S. aureus, investigation in these strains of genes encoding toxins (sea, seb, sec, sed, tst), biofilm (icaA, icaC, icaD, bap), leukocidin (luk-PV) oxacillin resistance by mecA gene detection and susceptibility testing (12 antibiotics). Messenger RNA expression was evaluated by RT-PCR in isolates carrying toxin and biofilm genes. Biofilm formation was also evaluated phenotypically by adherence to polystyrene plates. The clonal profile of S. aureus was investigated by pulsed-field gel electrophoresis. A total of 473 milk samples were collected from 242 animals on three farms and 20 S. aureus strains were isolated and none carried the mecA gene. The two sec gene-positive isolates and the isolates carrying the tst and luk-PV genes were positive by RT-PCR. Staphylococcus aureus isolated from the three flocks studied showed high susceptibility to the drugs tested and none was biofilm producer, indicating that biofilm formation was not a virulence factor causing infection by these strains. The typing of 17 S. aureus isolates revealed the presence of a common clone on the three farms studied, and the presence and expression of the sec and tst genes in one strain of this clone suggest the possible acquisition of virulence genes by this clone, a fact that is important for animal health and food hygiene. PMID:26273271

  12. Cancer antigens are expressed in a carcinogen-transformed Bloom syndrome B-lymphoblastoid cell line

    International Nuclear Information System (INIS)

    Shiraishi, Yukimasa; Soma, Hiroaki

    1988-01-01

    The authors have cloned malignant cells carrying specific antigens associated with ovarian cancer (OVC) and malignant lymphoma (ML) from BS-SHI-4M cells, a line derived from a 1-methyl-3-nitro-1-nitrosoguanidine-treated B-lymphoblastoid cell line isolated from a patient with Bloom syndrome. Since BS-SHI-4M cells react with sera from various individual cancer patients at relatively low frequencies (2-9%), as detected by an indirect immunofluorescence technique, cell clones that specifically react with sera from patients with OVC and ML were separated by the panning method in which polystyrene dishes were coated with sera from OVC and ML patients and cells with the corresponding antigens bound to the dishes. Subsequent cloning by limiting dilution provided cell clones highly enriched for OVC- and ML-associated antigens. Karyotype analyses revealed that cell clones with OVC and ML antigens had common marker chromosomes. Interestingly, in cell clones with a strong OVC antigen response, the distal part of the Y chromosome (Yq11) was missing in 100% of the cells. Therefore the cell line BS-SHI-4M appears to be a reservoir of cell clones each of which carries a specific tumor antigen and thus provides a potential tool for rapid serological diagnosis of cancer

  13. Identification of cDNA clones expressing immunodiagnostic antigens from Trichinella spiralis

    International Nuclear Information System (INIS)

    Zarlenga, D.; Gamble, H.R.

    1987-01-01

    A cDNA expression library was built in lambda gt11 phage using poly A mRNA isolated from Trichinella spiralis muscle stage larvae. This library was screened with rabbit antibodies to parasite excretory-secretory (ES) products and greater than 180 clones were isolated. Thirteen clones producing highly immunogenic protein antigens were plaque purified and rescreened with pig antisera to T.spiralis, Trichuris suis or Ascaris suum to identify clones producing epitopes specific to T.spiralis ES products, only. Two clones, TsAc-2 and TsAc-8, which displayed strong interactions with pig antisera to T. spiralis were lysogenized in E. coli Y1089 and the protein extracted. Western blots of the crude fusion proteins revealed molecular weights of 133 kD and 129 kD, respectively. Northern blot analysis of total RNA with 32 P labelled cDNA:lambda gt11 probes indicated single RNA transcripts for each clone with molecular sizes corresponding to 800-850 nucleotides. dscDNA inserts were estimated by southern blot analysis to be 500 bp and 340 bp, respectively, with no cross-hybridization observed between the cloned sequences. Dot blots using pig sera to screen crude fusion protein preparations, total bacterial protein (negative controls) and crude worm extract or ES products from T.spiralis, T.suis and A.suum (positive controls) corroborated the specificity and sensitivity of these clones as potential diagnostic antigens for swine trichinellosis

  14. Cloning of the gene encoding the δ subunit of the human T-cell receptor reveals its physical organization within the α-subunit locus and its involvement in chromosome translocations in T-cell malignancy

    International Nuclear Information System (INIS)

    Isobe, M.; Russo, G.; Haluska, F.G.; Croce, C.M.

    1988-01-01

    By taking advantage of chromosomal walking techniques, the authors have obtained clones that encompass the T-cell receptor (TCR) δ-chain gene. They analyzed clones spanning the entire J α region extending 115 kilobases 5' of the TCR α-chain constant region and have shown that the TCR δ-chain gene is located over 80 kilobases 5' of C α . TCR δ-chain gene is rearranged in the γ/δ-expressing T-cell line Peer and is deleted in α/β-expressing T-cell lines. Sequence analysis of portions of this genomic region demonstrates its identity with previously described cDNA clones corresponding to the C δ and J δ segments. Furthermore, they have analyzed a t(8;14)-(q24;q11) chromosome translocation from a T-cell leukemia and have shown that the J δ segment is rearranged in cells deriving from this tumor and probably directly involved in the translocation. Thus, the newly clones TCR δ chain is implicated in the genesis of chromosome translocations in T-cell malignancies carrying cytogenetic abnormalities of band 14q11

  15. Islamic perspectives on human cloning.

    Science.gov (United States)

    Sadeghi, Mahmoud

    2007-01-01

    The present paper seeks to assess various views from Islamic jurists relating to human cloning, which is one of the controversial topics in the recent past. Taking Islamic jurisprudence principles, such as the rule of necessity for self preservation and respect for human beings, the rule of la darar wa la dirar ('the necessity to refrain from causing harm to oneself and others') and the rule of usr wa haraj, one may indicate that if human cloning could not be prohibited, as such, it could still be opposed because it gives way to various harmful consequences, which include family disorder, chaos in the clone's family relationships, physical and mental diseases for clones and suffering of egg donors and surrogate mothers. However with due attention to the fact that the reasons behind the prohibition of abortion only restrict the destruction of human embryos in their post-implantation stages, human cloning for biomedical research and exploitation of stem cells from cloned embryos at the blastocyst stage for therapeutic purposes would be acceptable.

  16. Isolation and culture of larval cells from C. elegans.

    Directory of Open Access Journals (Sweden)

    Sihui Zhang

    Full Text Available Cell culture is an essential tool to study cell function. In C. elegans the ability to isolate and culture cells has been limited to embryonically derived cells. However, cells or blastomeres isolated from mixed stage embryos terminally differentiate within 24 hours of culture, thus precluding post-embryonic stage cell culture. We have developed an efficient and technically simple method for large-scale isolation and primary culture of larval-stage cells. We have optimized the treatment to maximize cell number and minimize cell death for each of the four larval stages. We obtained up to 7.8×10(4 cells per microliter of packed larvae, and up to 97% of adherent cells isolated by this method were viable for at least 16 hours. Cultured larval cells showed stage-specific increases in both cell size and multinuclearity and expressed lineage- and cell type-specific reporters. The majority (81% of larval cells isolated by our method were muscle cells that exhibited stage-specific phenotypes. L1 muscle cells developed 1 to 2 wide cytoplasmic processes, while L4 muscle cells developed 4 to 14 processes of various thicknesses. L4 muscle cells developed bands of myosin heavy chain A thick filaments at the cell center and spontaneously contracted ex vivo. Neurons constituted less than 10% of the isolated cells and the majority of neurons developed one or more long, microtubule-rich protrusions that terminated in actin-rich growth cones. In addition to cells such as muscle and neuron that are high abundance in vivo, we were also able to isolate M-lineage cells that constitute less than 0.2% of cells in vivo. Our novel method of cell isolation extends C. elegans cell culture to larval developmental stages, and allows use of the wealth of cell culture tools, such as cell sorting, electrophysiology, co-culture, and high-resolution imaging of subcellular dynamics, in investigation of post-embryonic development and physiology.

  17. DNA cloning: a practical approach. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Glover, D M [ed.

    1985-01-01

    This book is written for the advanced molecular biologist who needs a detailed discussion of cloning technology. Topics of discussion include: genomic library cloning (size of a genomic library, screening methods, chromosome walking, host cell genetics, and general features of bacteriophage Iambda); use of gt10 and gt11 cDNA lambda vectors and general cDNA cloning; RNase H-Pol I cDNA synthesis; method of detecting fusion proteins produced in bacteria; pEMBL family of double-stranded plasmid vectors that can be used to generate single strands; Escherichia coli transformation; production of mutations in cloned sequences; and cloning in gram negative bacteria.

  18. Measurement of in vivo HGPRT-deficient mutant cell frequency using a modified method for cloning human peripheral blood T-lymphocytes

    International Nuclear Information System (INIS)

    Hakoda, Masayuki; Akiyama, Mitoshi; Kyoizumi, Seishi; Kobuke, Kyoko; Awa, A.A.

    1987-07-01

    Approximately 80 % of human peripheral blood T-lymphocytes could be cloned in the presence of crude Interleukin-2, phytohemagglutinin, and X-irradiated autologous lymphocytes and Raji B-cells. This modified cloning method was used to measure the in vivo frequency of HGPRT-deficient mutant T-lymphocytes. Repeated experiments using blood from the same individuals revealed that the frequency of mutant cells was almost constant for each individual even though the cloning efficiency of lymphocytes varied somewhat from experiment to experiment. Approximately 80 % of both wild-type unselected and 6-thioguanine-resistant colonies had helper/inducer and about 20 % had suppressor/cytotoxic T-lymphocyte markers. No difference was observed in the distribution of lymphocyte subsets between wild and mutant lymphocyte colonies. (author)

  19. Cloning and characterization of a pathogen-induced chitinase in Brassica napus

    DEFF Research Database (Denmark)

    Rasmussen, U.; Bojsen, K.; Collinge, D.B.

    1992-01-01

    A chitinase cDNA clone from rapeseed (Brassica napus L. ssp. oleifera) was isolated. The cDNA clone, ChB4, represents a previously purified and characterized basic chitinase isozyme. The longest open reading frame in ChB4 encodes a polypeptide of 268 amino acids. This polypeptide consists of a 24...

  20. Molecular cloning of the human gene for von Willebrand factor and identification of the transcription initiation site

    International Nuclear Information System (INIS)

    Collins, C.J.; Underdahl, J.P.; Levene, R.B.; Ravera, C.P.; Morin, M.J.; Dombalagian, M.J.; Ricca, G.; Livingston, D.M.; Lynch, D.C.

    1987-01-01

    A series of overlapping cosmid genomic clones have been isolated that contain the entire coding unit of the human gene for van Willebrand factor (vWf), a major component of the hemostatic system. The cloned segments span ≅ 175 kilobases of human DNA sequence, and hybridization analysis suggest that the vWf coding unit is ≅150 kilobases in length. Within one of these clones, the vWF transcription initiation site has been mapped and a portion of the vWf promoter region has been sequenced, revealing a typical TATA box, a downstream CCAAT box, and a perfect downstream repeat of the 8 base pairs containing the transcription start site. Sequencing of a segment of another genomic clone has revealed the vWF translation termination codon. Where tested, comparative restriction analysis of cloned and chromosomal DNA segments strongly suggests that no major alterations occurred during cloning and that there is only one complete copy of the vWf gene in the human haploid genome. Similar analyses of DNA from vWf-producing endothelial cells and nonexpressing leukocytes suggest that vWf gene expression is not accompanied by gross genomic rearrangements. In addition, there is significant homology of C-terminal coding sequences among the vWf genes of several vertebrate species

  1. Climbing Mount Efficiency--small steps, not giant leaps towards higher cloning success in farm animals.

    Science.gov (United States)

    Oback, Björn

    2008-07-01

    Despite more than a decade of research efforts, farm animal cloning by somatic cell nuclear transfer (SCNT) is still frustratingly inefficient. Inefficiency manifests itself at different levels, which are currently not well integrated. At the molecular level, it leads to widespread genetic, epigenetic and transcriptional aberrations in cloned embryos. At the organismal level, these genome-wide abnormalities compromise development of cloned foetuses and offspring. Specific molecular defects need to be causally linked to specific cloned phenotypes, in order to design specific treatments to correct them. Cloning efficiency depends on the ability of the nuclear donor cell to be fully reprogrammed into an embryonic state and the ability of the enucleated recipient cell to carry out the reprogramming reactions. It has been postulated that reprogrammability of the somatic donor cell epigenome is influenced by its differentiation status. However, direct comparisons between cells of divergent differentiation status within several somatic lineages have found no conclusive evidence for this. Choosing somatic stem cells as donors has not improved cloning efficiency, indicating that donor cell type may be less critical for cloning success. Different recipient cells, on the other hand, vary in their reprogramming ability. In bovine, using zygotes instead of oocytes has increased cloning success. Other improvements in livestock cloning efficiency include better coordinating donor cell type with cell cycle stage and aggregating cloned embryos. In the future, it will be important to demonstrate if these small increases at every step are cumulative, adding up to an integrated cloning protocol with greatly improved efficiency.

  2. Human cloning: Eastern Mediterranean Region perspective.

    Science.gov (United States)

    Abdur Rab, M; Khayat, M H

    2006-01-01

    Recent advances in genomics and biotechnology have ushered in a new era in health development. Therapeutic cloning possesses enormous potential for revolutionizing medical and therapeutic techniques. Cloning technology, however, is perceived as having the potential for reproductive cloning, which raises serious ethical and moral concerns. It is important that the Islamic countries come to a consensus on this vital issue. Developing science and technology for better health is a religious and moral obligation. There is an urgent need for Muslim scholars to discuss the issue of stem cell research and cloning rationally; such dialogue will not only consider the scientific merits but also the moral, ethical and legal implications.

  3. Cloning, expression, and chromosome mapping of human galectin-7

    DEFF Research Database (Denmark)

    Madsen, Peder; Rasmussen, H H; Flint, T

    1995-01-01

    The galectins are a family of beta-galactoside-binding proteins implicated in modulating cell-cell and cell-matrix interactions. Here we report the cloning and expression of a novel member of this family (galectin-7) that correspond to IEF (isoelectric focusing) 17 (12,700 Da; pI, 7.6) in the human...... keratinocyte protein data base, and that is strikingly down-regulated in SV40 transformed keratinocytes (K14). The cDNA was cloned from a lambda gt11 cDNA expression library using degenerated oligodeoxyribonucleotides back-translated from an IEF 17 peptide sequence. The protein encoded by the galectin-7 clone......14 keratinocytes imply a role in cell-cell and/or cell-matrix interactions necessary for normal growth control. The galectin-7 gene was mapped to chromosome 19. Udgivelsesdato: 1995-Mar-17...

  4. Altering histone acetylation status in donor cells with suberoylanilide hydroxamic acid does not affect dog cloning efficiency.

    Science.gov (United States)

    Kim, Min Jung; Oh, Hyun Ju; Kim, Geon A; Suh, Han Na; Jo, Young Kwang; Choi, Yoo Bin; Kim, Dong Hoon; Han, Ho Jae; Lee, Byeong Chun

    2015-10-15

    Although dog cloning technology has been applied to conservation of endangered canids, propagation of elite dogs, and production of transgenic dogs, the efficiency of cloning is still very low. To help overcome this problem, we evaluated the effect of treating donor cells with suberoylanilide hydroxamic acid (SAHA), a histone deacetylase inhibitor, on dog cloning efficiency. Relative messenger RNA expressions of the bax1/bcl2 ratio and Dnmt1 in fibroblasts treated with different concentrations (0, 1, 10, 50 μM) of SAHA and durations (0, 20, 44 hours) were compared. Treatment with 1 μM for 20 hours showed significantly lower bax1/bcl2 and Dnmt1 transcript abundance. Acetylation of H3K9 was significantly increased after SAHA treatment, but H4K5, H4K8 and H4K16 were not changed. After SCNT using control or donor cells treated with SAHA, a total of 76 and 64 cloned embryos were transferred to seven and five recipients, respectively. Three fetuses were diagnosed in both control and SAHA-treated groups by ultrasonography 29 days after the embryo transfer, but there was no significant difference in the pregnancy rate (4.2% vs. 4.3%). In conclusion, although SAHA treatment as used in this study significantly decreased bax1/bcl2 and Dnmt1 transcripts of donor nuclei, as well as increased H3 acetylation, it was not enough to increase in vivo developmental competence of cloned dog embryos. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Establishment and characterization of a spontaneously immortalized trophoblast cell line (HPT-8) and its hepatitis B virus-expressing clone.

    Science.gov (United States)

    Zhang, Lei; Zhang, Weilu; Shao, Chen; Zhang, Jingxia; Men, Ke; Shao, Zhongjun; Yan, Yongping; Xu, Dezhong

    2011-08-01

    Most trophoblast cell lines currently available to study vertical transmission of hepatitis B virus (HBV) are immortalized by viral transformation. Our goal was to establish and characterize a spontaneously immortalized human first-trimester trophoblast cell line and its HBV-expressing clone. Chorionic villi of Asian human first-trimester placentae were digested with trypsin and collagenase I to obtain the primary trophoblast cell culture. A spontaneously immortalized trophoblast cell line (HPT-8) was analyzed by scanning and transmission electron microscopy, cell cycle analysis, immunohistochemistry and immunofluorescence. HPT-8 cells were stably transfected with the adr subtype of HBV (HPT-8-HBV) and characterized by PCR and enzyme-linked immunosorbent assay. We obtained a clonal derivative of a spontaneously immortalized primary cell clone (HPT-8). HPT-8 cells were epithelioid and polygonal, and formed multinucleate, giant cells. They exhibited microvilli, distinct desmosomes between adjacent cells, abundant endoplasm, lipid inclusions and glycogen granules, which are all characteristic of cytotrophoblasts. HPT-8 cells expressed cytokeratin 7, cytokeratin 18, vimentin, cluster of differentiation antigen 9, epidermal growth factor receptor, stromal cell-derived factor 1 and placental alkaline phosphatase. They secreted prolactin, estradiol, progesterone and hCG, and were positive for HLA-G, a marker of extravillous trophoblasts. HPT-8-HBV cells were positive for HBV relaxed-circular, covalently closed circular DNA and pre-S sequence. HPT-8-HBV cells also produced and secreted HBV surface antigen and HBV e antigen. We established a trophoblast cell line, HPT-8 and its HBV-expressing clone which could be valuable in exploring the mechanism of HBV viral integration in human trophoblasts during intrauterine infection.

  6. Expression of a human gene for polyamine transport in Chinese-hamster ovary cells.

    Science.gov (United States)

    Byers, T L; Wechter, R; Nuttall, M E; Pegg, A E

    1989-01-01

    A molecular-genetic approach towards isolating mammalian polyamine-transport genes and their encoded proteins was devised involving the production of Chinese-hamster ovary (CHO) cells expressing a human polyamine-transport protein. CHO cells and a polyamine-transport-deficient CHO mutant cell line (CHOMG) were equally sensitive to the antiproliferative effects of alpha-difluoromethylornithine (DFMO), which blocked endogenous polyamine synthesis. Exposure to exogenous polyamines increased intracellular polyamine levels and reversed this DFMO-induced cytostasis in the CHO cells, but not in the CHOMG cells. CHOMG cells were therefore transfected with human DNA (isolated from HT-29 colon carcinoma cells) and cells expressing the human polyamine-transport system were identified by the ability of these cells to grow in a medium containing DFMO and polyamines. A number of different positive clones were identified and shown to have the capacity for polyamine uptake and an increased sensitivity to the toxic effects of the polyamine analogue methylglyoxal bis(guanylhydrazone). Differences in these properties between the clones are consistent with a multiplicity of polyamine-transport systems. Some clones also showed a change in growth characteristics, which may indicate a relationship between genes involved in the polyamine-transport system and in cell proliferation. PMID:2512913

  7. Molecular cloning and expression in mammalian cells of ricin B chain

    International Nuclear Information System (INIS)

    Chang, M.

    1987-01-01

    In these studies, the cDNA encoding the B chain of ricin has been cloned and expressed in monkey kidney COS-M6 cells. The recombinant B chain was detected by labeling the transfected cells with 35 S-methionine and 35 S-cysteine and demonstrating secretion of a protein with a Mr of 30-32,000 which was not present in the medium of mock-transfected COS-M6 cells. This protein was specifically immunoprecipitated by an anti-ricin or anti-B chain antibody. The amount of recombinant B chain secreted by the COS-M6 cells was determined by radioimmunoassay to be 1-10 ng/ml of media. Virtually all the recombinant B chain formed active ricin when mixed with native A chain; it could also bind as effectively as native B chain to the galactose-containing glycoprotein, asialofetuin. These results indicate that the vast majority of recombinant B chains secreted into the medium of the COS-M6 cells retain biological function

  8. Stability of the phenotypic reversion of x-ray transformed C3H/10T1/2 cells depends on cellular proliferation after subcultivation at low cell density

    International Nuclear Information System (INIS)

    Brouty-Boye, D.; Gresser, I.; Bandu, M.T.

    1982-01-01

    Reversion from the transformed to the non-transformed phenotype could be obtained by seeding X-ray transformed C3H/10T1/2 cells at low cell density. Cloned revertant cells of varying degrees of reversion were obtained depending on the time they were isolated after one subculture at low cell density. Most of the revertants isolated 7 and 10 days after seeding at very low cell density eventually returned to the transformed phenotype when passaged serially at high cell density. In contrast, 25-35% of the revertants isolated 17-20 days after seeding at low cell density maintained the non-transformed phenotype despite subsequent serial passages at high cell density. The finding that there was a direct relationship between the time during which transformed cells seeded at low cell density multiplied and the number of stable revertant clones obtained, suggests the possibility that reversion from the transformed to the non-transformed phenotype may be a multistep process. Revertant cells displayed a chromosomal pattern characteristic of the transformed cells rather than that of the parental non-transformed 10T1/2 cells. (author)

  9. In a patient with biclonal Waldenstrom macroglobulinemia only one clone expands in three-dimensional culture and includes putative cancer stem cells.

    Science.gov (United States)

    Kirshner, Julia; Thulien, Kyle J; Kriangkum, Jitra; Motz, Sarah; Belch, Andrew R; Pilarski, Linda M

    2011-02-01

    A small percentage of cases of Waldenstrom macroglobulinemia (WM) present with biclonality, defined here as the rearrangement of two distinct VDJ gene segments. Here we investigated the expansion of two clones from a patient with WM expressing molecularly detectable clonotypic gene rearrangements, one V(H)3 and one V(H)4. Biclonality was determined in blood and bone marrow mononuclear cells using real-time quantitative PCR (RQ-PCR). V(H)4 expressing cells but not V(H)3 expressing cells underwent clonal expansion in 3-D culture of reconstructed WM bone marrow. After 3-D culture, secondary culture in a colony forming unit assay, and RQ-PCR, only the V(H)4 clone was shown to harbor a subpopulation with characteristics of cancer stem cells, including proliferative quiescence, self-regeneration, and the ability to generate clonotypic progeny, suggesting that the V(H)4, but not the V(H)3, clone is clinically significant. Enrichment of potential WM stem cells in 3-D cultures holds promise for monitoring their response to treatment and for testing new therapies.

  10. Molecular cloning and biological characterization of the human excision repair gene ERCC-3

    International Nuclear Information System (INIS)

    Weeda, G.; van Ham, R.C.; Masurel, R.; Westerveld, A.; Odijk, H.; de Wit, J.; Bootsma, D.; van der Eb, A.J.; Hoeijmakers, J.H.

    1990-01-01

    In this report we present the cloning, partial characterization, and preliminary studies of the biological activity of a human gene, designated ERCC-3, involved in early steps of the nucleotide excision repair pathway. The gene was cloned after genomic DNA transfection of human (HeLa) chromosomal DNA together with dominant marker pSV3gptH to the UV-sensitive, incision-defective Chinese hamster ovary (CHO) mutant 27-1. This mutant belongs to complementation group 3 of repair-deficient rodent mutants. After selection of UV-resistant primary and secondary 27-1 transformants, human sequences associated with the induced UV resistance were rescued in cosmids from the DNA of a secondary transformant by using a linked dominant marker copy and human repetitive DNA as probes. From coinheritance analysis of the ERCC-3 region in independent transformants, we deduce that the gene has a size of 35 to 45 kilobases, of which one essential segment has so far been refractory to cloning. Conserved unique human sequences hybridizing to a 3.0-kilobase mRNA were used to isolate apparently full-length cDNA clones. Upon transfection to 27-1 cells, the ERCC-3 cDNA, inserted in a mammalian expression vector, induced specific and (virtually) complete correction of the UV sensitivity and unscheduled DNA synthesis of mutants of complementation group 3 with very high efficiency. Mutant 27-1 is, unlike other mutants of complementation group 3, also very sensitive toward small alkylating agents. This unique property of the mutant is not corrected by introduction of the ERCC-3 cDNA, indicating that it may be caused by an independent second mutation in another repair function. By hybridization to DNA of a human x rodent hybrid cell panel, the ERCC-3 gene was assigned to chromosome 2, in agreement with data based on cell fusion

  11. Quantitative discrimination of Aggregatibacter actinomycetemcomitans highly leukotoxic JP2 clone from non-JP2 clones in diagnosis of aggressive periodontitis

    Directory of Open Access Journals (Sweden)

    Yoshida Akihiro

    2012-10-01

    Full Text Available Abstract Background Aggregatibacter actinomycetemcomitans is the etiological agent of periodontitis, and there is a strong association between clone JP2 and aggressive periodontitis in adolescents of African descent. The JP2 clone has an approximately 530-bp deletion (∆530 in the promoter region of the lkt/ltx gene, which encodes leukotoxin, and this clone has high leukotoxic activity. Therefore, this clone is very important in aggressive periodontitis. To diagnose this disease, culture methods and conventional PCR techniques are used. However, quantitative detection based on qPCR for the JP2 clone has not been developed due to genetic difficulties. In this study, we developed a qPCR-based quantification method specific to the JP2 clone. Methods Based on our analysis of the DNA sequence of the lkt/ltx gene and its flanking region, we designed a reverse primer specific for the ∆530 deletion border sequence and developed a JP2-specific PCR-based quantification method using this primer. We also analyzed the DNA sequence of the ∆530 locus and found it to be highly conserved (97–100% among 17 non-JP2 strains. Using the ∆530 locus, we designed a qPCR primer–probe set specific to non-JP2 clones. Next, we determined the numbers of JP2 and non-JP2 clone cells in the periodontal pockets of patients with aggressive periodontitis. Results The JP2-specific primers specifically amplified the genomic DNA of the A. actinomycetemcomitans JP2 clone and did not react with other bacterial DNA, whereas the non-JP2 specific primers reacted only with A. actinomycetemcomitans non-JP2 clones. Samples from the 88 periodontal sites in the 11 patients with aggressive periodontitis were analyzed. The bacterial cell numbers in 88 periodontal sites ranged from 0 to 4.8 × 108 (mean 1.28 × 107 for JP2 clones and from 0 to 1.6 × 106 for non-JP2 clones (mean 1.84 × 105. There were significant differences in the JP2 cell number between a clinical attachment level

  12. Prevalence of polyreactive innate clones among graft--infiltrating B cells in human cardiac allograft vasculopathy.

    Science.gov (United States)

    Chatterjee, Debanjana; Moore, Carolina; Gao, Baoshan; Clerkin, Kevin J; See, Sarah B; Shaked, David; Rogers, Kortney; Nunez, Sarah; Veras, Yokarla; Addonizio, Linda; Givertz, Michael M; Naka, Yoshifumi; Mancini, Donna; Vasilescu, Rodica; Marboe, Charles; Restaino, Susan; Madsen, Joren C; Zorn, Emmanuel

    2018-03-01

    Cardiac allograft vasculopathy (CAV) has been associated with graft-infiltrating B cells, although their characteristics are still unclear. In this study we examined the frequency, localization and reactivity profile of graft-infiltrating B cells to determine their contribution to the pathophysiology of CAV. B cells, plasma cells and macrophages were examined by immunohistochemistry in 56 allografts with CAV, 49 native failed hearts and 25 autopsy specimens. A total of 102 B-cell clones were immortalized directly from the infiltrates of 3 fresh cardiac samples with CAV. Their secreted antibodies were assessed using enzyme-linked immunoassay and flow cytometry. B-cell infiltration was observed around coronary arteries in 93% of allograft explants with CAV. Comparatively, intragraft B cells were less frequent and less dense in the intraventricular myocardium from where routine biopsies are obtained. Plasma cells and macrophages were also detected in 85% and 95% of explants, respectively. Remarkably, B-cell infiltrates were not associated with circulating donor-specific antibodies (DSA) or prior episodes of antibody-mediated rejection (AMR). Among all B-cell clones generated from 3 explants with CAV, a majority secreted natural antibodies reactive to multiple autoantigens and apoptotic cells, a characteristic of innate B cells. Our study reveals a high frequency of infiltrating B cells around the coronary arteries of allografts with CAV, independent of DSA or AMR. These cells are enriched for innate B cells with a polyreactive profile. The findings shift the focus from conventional DSA-producing B cells to the potentially pathogenic polyreactive B cells in the development of clinical CAV. Copyright © 2018 International Society for the Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.

  13. Human cloning and 'posthuman' society.

    Science.gov (United States)

    Blackford, Russell

    2005-01-01

    Since early 1997, when the creation of Dolly the sheep by somatic cell nuclear transfer was announced in Nature, numerous government reports, essays, articles and books have considered the ethical problems and policy issues surrounding human reproductive cloning. In this article, I consider what response a modern liberal society should give to the prospect of human cloning, if it became safe and practical. Some opponents of human cloning have argued that permitting it would place us on a slippery slope to a repugnant future society, comparable to that portrayed in Aldous Huxley's novel, Brave New World. I conclude that, leaving aside concerns about safety, none of the psychological or social considerations discussed in this article provides an adequate policy justification for invoking the state's coercive powers to prevent human cloning.

  14. Expanded cellular clones carrying replication-competent HIV-1 persist, wax, and wane.

    Science.gov (United States)

    Wang, Zheng; Gurule, Evelyn E; Brennan, Timothy P; Gerold, Jeffrey M; Kwon, Kyungyoon J; Hosmane, Nina N; Kumar, Mithra R; Beg, Subul A; Capoferri, Adam A; Ray, Stuart C; Ho, Ya-Chi; Hill, Alison L; Siliciano, Janet D; Siliciano, Robert F

    2018-03-13

    The latent reservoir for HIV-1 in resting CD4 + T cells is a major barrier to cure. Several lines of evidence suggest that the latent reservoir is maintained through cellular proliferation. Analysis of this proliferative process is complicated by the fact that most infected cells carry defective proviruses. Additional complications are that stimuli that drive T cell proliferation can also induce virus production from latently infected cells and productively infected cells have a short in vivo half-life. In this ex vivo study, we show that latently infected cells containing replication-competent HIV-1 can proliferate in response to T cell receptor agonists or cytokines that are known to induce homeostatic proliferation and that this can occur without virus production. Some cells that have proliferated in response to these stimuli can survive for 7 d while retaining the ability to produce virus. This finding supports the hypothesis that both antigen-driven and cytokine-induced proliferation may contribute to the stability of the latent reservoir. Sequencing of replication-competent proviruses isolated from patients at different time points confirmed the presence of expanded clones and demonstrated that while some clones harboring replication-competent virus persist longitudinally on a scale of years, others wax and wane. A similar pattern is observed in longitudinal sampling of residual viremia in patients. The observed patterns are not consistent with a continuous, cell-autonomous, proliferative process related to the HIV-1 integration site. The fact that the latent reservoir can be maintained, in part, by cellular proliferation without viral reactivation poses challenges to cure.

  15. Mammalian mediator 19 mediates H1299 lung adenocarcinoma cell clone conformation, growth, and metastasis.

    Science.gov (United States)

    Xu, Lu-Lu; Guo, Shu-Liang; Ma, Su-Ren; Luo, Yong-Ai

    2012-01-01

    Mammalian mediator (MED) is a multi-protein coactivator that has been identified by several research groups. The involvement of the MED complex subunit 19 (MED 19) in the metastasis of lung adenocarcinoma cell line (H1299), which expresses the MED 19 subunit, was here investigated. When MED 19 expression was decreased by RNA interference H1299 cells demonstrated reduced clone formation, arrest in the S phase of the cell cycle, and lowered metastatic capacity. Thus, MED 19 appears to play important roles in the biological behavior of non-small cell lung carcinoma cells. These findings may be important for the development of novel lung carcinoma treatments.

  16. Duration of gestation in pregnant dogs carrying cloned fetuses.

    Science.gov (United States)

    Kim, Min Jung; Oh, Hyun Ju; Park, Jung Eun; Kim, Geon A; Park, Eun Jung; Jo, Young Kwang; Lee, Byeong Chun

    2013-01-15

    The aim of this study was to investigate gestation duration and the physiologic characteristics of pregnant dogs bearing cloned fetuses, especially in the prepartum period. A retrospective study was performed to compare gestation duration in females pregnant with cloned (somatic cell nuclear transfer) fetuses (cloned group) with those bearing noncloned fetuses (control group), and effects of litter size, birth weight, and breed of somatic cell donors on gestation duration in the cloned group were evaluated. Clinical delivery onset signs associated with serum progesterone concentration and rectal temperature were also compared in both groups. The gestation duration calculated from day of ovulation was significantly longer in the cloned (62.8 ± 0.3 days) versus the control group (60.9 ± 0.5 days; P dogs bearing cloned fetuses might be because of the smaller litter size in this group. Also, the weaker drop in serum progesterone levels in the prepartum period in cloned dog pregnancies indicates that the parturition signaling process might be altered resulting in longer gestation periods. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Fluctuating fitness shapes the clone-size distribution of immune repertoires.

    Science.gov (United States)

    Desponds, Jonathan; Mora, Thierry; Walczak, Aleksandra M

    2016-01-12

    The adaptive immune system relies on the diversity of receptors expressed on the surface of B- and T cells to protect the organism from a vast amount of pathogenic threats. The proliferation and degradation dynamics of different cell types (B cells, T cells, naive, memory) is governed by a variety of antigenic and environmental signals, yet the observed clone sizes follow a universal power-law distribution. Guided by this reproducibility we propose effective models of somatic evolution where cell fate depends on an effective fitness. This fitness is determined by growth factors acting either on clones of cells with the same receptor responding to specific antigens, or directly on single cells with no regard for clones. We identify fluctuations in the fitness acting specifically on clones as the essential ingredient leading to the observed distributions. Combining our models with experiments, we characterize the scale of fluctuations in antigenic environments and we provide tools to identify the relevant growth signals in different tissues and organisms. Our results generalize to any evolving population in a fluctuating environment.

  18. Microbial diversity of mangrove sediment in Shenzhen Bay and gene cloning, characterization of an isolated phytase-producing strain of SPC09 B. cereus.

    Science.gov (United States)

    Zhang, Shengpeng; Liao, Shao-An; Yu, Xiaoyuan; Lu, Hongwu; Xian, Jian-An; Guo, Hui; Wang, Anli; Xie, Jian

    2015-06-01

    Phytases hydrolyze phytate to release inorganic phosphate, which decreases the requirement for phosphorus in fertilizers for crops and thus reduces environmental pollutants. This study analyzed microbial communities in rhizosphere sediment, collected in September 2012 from Shenzhen Bay, Guangdong, China, using high-throughput pyrosequencing; the results showed that the dominant taxonomic phyla were Chloroflexi, Firmicutes, and Proteobacteria, and the proportion of the beneficial bacteria, Bacillus, was 4.95 %. Twenty-nine culturable, phytase-producing bacteria were isolated, their phosphorus solubilization capacity was analyzed, and they were taxonomically characterized. Their phylogenetic placement was determined using 16S ribosomal RNA (rRNA) gene sequence analysis. The result shows that most of the isolates are members of the order Bacillales, although seven strains of Enterobacteriales, two strains of Pseudomonadales, and one strain of Oceanospirillales were also identified. The phytase gene was cloned from SPC09, Bacillus cereus, which showed the highest phosphorus solubilizing ability among the isolated strains. The gene encoded a primary translation product of 335 amino acids. A construct including the 1005-nt ORF fragment, Bc-phy, was transformed into Escherichia coli. The recombinant phytase was produced and purified, which revealed the temperature optima at 60 °C and pH optima at 6.5. The assessment by quantitative PCR (qPCR) showed an abundance of bacteria containing the Bc-phy gene; the level was generally higher in the mangrove forest than in the tidal flats and in surface soil compared to bottom soil, and the highest value was obtained in June. Herein, we report on the cloning, characterization, and activity of a novel phytase isolated from a mangrove system.

  19. Molecular cloning and recombinant expression of the VP28 carboxyl-terminal hydrophilic region from a brazilian white spot syndrome virus isolate

    Directory of Open Access Journals (Sweden)

    Patricia Braunig

    2011-04-01

    Full Text Available In the present study, a fragment of the VP28 coding sequence from a Brazilian WSSV isolate (BrVP28 was cloned, sequenced and expressed in E. coli BL21(DE3 pLysS strain in order to produce the VP28 carboxyl-terminal hydrophilic region. The expression resulted in a protein of about 21 kDa, which was purified under denaturing conditions, resulting in a final highly purified BrVP28 preparation. The recombinant protein obtained can be used in several biotechnology applications, such as the production of monoclonal antibodies which could be used in the development of diagnostic tools as well as in the studies on the characterization of white spot syndrome virus (WSSV isolated in Brazil.

  20. The isolated anatase for dye sensitized solar cell

    Energy Technology Data Exchange (ETDEWEB)

    Ilmi, Irfan, E-mail: irfan.ilmi149@gmail.com [Postgraduate Program, Department of Chemistry, Universitas Gadjah Mada, Yogyakarta 55281 Indonesia (Indonesia); Functional Coating Materials Research Group, Department of Chemistry, Universitas Gadjah Mada, Yogyakarta 55281 Indonesia (Indonesia); Kartin, Indriana; Suyanta [Functional Coating Materials Research Group, Department of Chemistry, Universitas Gadjah Mada, Yogyakarta 55281 Indonesia (Indonesia); Department of Chemistry,Universitas Gadjah Mada, Yogyakarta 55281 Indonesia (Indonesia); Ohtani, Bunsho; Wang, Kunlei [Graduate School of Environmental and Earth Science, Hokkaido University Japan (Japan)

    2015-09-30

    The isolation of crystallite anatase from commercial TiO{sub 2} P25 Degussa was investigated. The aim of this research was to study of isolated anatase based DSSC as an effort to develop industrial DSSC. The crystal phase, crystallite size and crystal shape both of original P25 and isolated anatase were characterized by XRD and TEM. By observing DSSC parameters such as FF, Jsc and Voc resulted in cell test, the efficiency of samples based DSSC was known. The isolation of anatase crystal was done by dissolving P25 in ammonia catalyzed hydrogen peroxide solution for 15 hours followed by washing and drying. DSSC cell performance was evaluated by applying the isolated anantase and original P25 as photoanode in the Gratzel cell system. The observation of cell efficiency was measured under 100 mW /cm{sup 2} with active area 1.5 cm{sup 2}. X-ray diffraction pattern showed obviously that no rutile contaminant in produced isolated anatase. TEM image shows typical anatase crystal with the particle size 21 nm. Surface area measurement exhibits that surface area of isolated anatase was 64.7m{sup 2}/g. I-V measurement showed that the efficiency of anatase based cell and P25 based cell is 0.79% and 0.51% respectively.

  1. Isolation of Specific Clones from Nonarrayed BAC Libraries through Homologous Recombination

    Directory of Open Access Journals (Sweden)

    Mikhail Nefedov

    2011-01-01

    Full Text Available We have developed a new approach to screen bacterial artificial chromosome (BAC libraries by recombination selection. To test this method, we constructed an orangutan BAC library using an E. coli strain (DY380 with temperature inducible homologous recombination (HR capability. We amplified one library segment, induced HR at 42∘C to make it recombination proficient, and prepared electrocompetent cells for transformation with a kanamycin cassette to target sequences in the orangutan genome through terminal recombineering homologies. Kanamycin-resistant colonies were tested for the presence of BACs containing the targeted genes by the use of a PCR-assay to confirm the presence of the kanamycin insertion. The results indicate that this is an effective approach for screening clones. The advantage of recombination screening is that it avoids the high costs associated with the preparation, screening, and archival storage of arrayed BAC libraries. In addition, the screening can be conceivably combined with genetic engineering to create knockout and reporter constructs for functional studies.

  2. Comparative Genomic Analysis of Rapid Evolution of an Extreme-Drug-Resistant Acinetobacter baumannii Clone

    Science.gov (United States)

    Tan, Sean Yang-Yi; Chua, Song Lin; Liu, Yang; Høiby, Niels; Andersen, Leif Percival; Givskov, Michael; Song, Zhijun; Yang, Liang

    2013-01-01

    The emergence of extreme-drug-resistant (EDR) bacterial strains in hospital and nonhospital clinical settings is a big and growing public health threat. Understanding the antibiotic resistance mechanisms at the genomic levels can facilitate the development of next-generation agents. Here, comparative genomics has been employed to analyze the rapid evolution of an EDR Acinetobacter baumannii clone from the intensive care unit (ICU) of Rigshospitalet at Copenhagen. Two resistant A. baumannii strains, 48055 and 53264, were sequentially isolated from two individuals who had been admitted to ICU within a 1-month interval. Multilocus sequence typing indicates that these two isolates belonged to ST208. The A. baumannii 53264 strain gained colistin resistance compared with the 48055 strain and became an EDR strain. Genome sequencing indicates that A. baumannii 53264 and 48055 have almost identical genomes—61 single-nucleotide polymorphisms (SNPs) were found between them. The A. baumannii 53264 strain was assembled into 130 contigs, with a total length of 3,976,592 bp with 38.93% GC content. The A. baumannii 48055 strain was assembled into 135 contigs, with a total length of 4,049,562 bp with 39.00% GC content. Genome comparisons showed that this A. baumannii clone is classified as an International clone II strain and has 94% synteny with the A. baumannii ACICU strain. The ResFinder server identified a total of 14 antibiotic resistance genes in the A. baumannii clone. Proteomic analyses revealed that a putative porin protein was down-regulated when A. baumannii 53264 was exposed to antimicrobials, which may reduce the entry of antibiotics into the bacterial cell. PMID:23538992

  3. A cell clone strain from Mythimna separata (Lepidoptera: Noctuidae) highly susceptible to Autographa californica multiple nucleopolyhedrovirus (AcMNPV) and M. separata NPV (MsNPV).

    Science.gov (United States)

    Meng, Xiang-Qian; Zheng, Gui-Ling; Zhao, Chuan-De; Wan, Fang-Hao; Li, Chang-You

    2017-08-01

    In this study, we describe a cell line, Ms-10C, cloned from the line QAU-Ms-E-10 (simplified Ms-10), an embryonic line from Mythimna separata. The cloned cell line was significantly more sensitive to nucleopolyhedrovirus (NPV). Ms-10C cells were mainly spherical with a diameter of 14.42 ± 2.23 μm. DNA amplification fingerprinting (DAF) confirmed the profile of PCR-amplified bands of the cloned cell line was consistent with those of the parental cell line, Ms-10. The sequencing result of the mitochondrial cytochrome c oxidase I (mtCO I) fragment confirmed that the amplified 636-bps mtCOI fragment was 100% identical to that of M. separata. Its chromosomes exhibited the typical characters of lepidopteran cell lines. Its population doubling time was 42.2 h at 27°C. Ms-10C was more sensitive than Ms-10 to both Autographa californica multiple nucleopolyhedrovirus (AcMNPV) and M. separata nucleopolyhedrovirus (MsNPV). At 4 d post infection, the infection rates of two viruses reached 94.2 and 92.3%, respectively. The availability of this cell clone strain will provide a useful tool for the basic research on nucleopolyhedrovirus and for potential application in expression of recombinant proteins with baculovirus expression vector system.

  4. Generation and functional analysis of T cell lines and clones specific for schistosomula released products (SRP-A).

    Science.gov (United States)

    Damonneville, M; Velge, F; Verwaerde, C; Pestel, J; Auriault, C; Capron, A

    1987-01-01

    Antigens present in the products released by the larval stage of schistosome (SRP-A) were shown to induce a strong cytotoxic and protective IgE response both in the rat and the monkey. T cell lines and clones specific for SRP-A or 26 kD antigens which are the main target of the cytotoxic IgE have been derived. The passive transfer of SRP-A specific T lymphocytes into infected rats led to an increase of the IgE response, conferring a significant level of protection to the rats. In coculture assays in vitro, these cell lines significantly enhanced the production of IgE by SRP-A sensitized rat spleen cells. This helper effect on the IgE response was confirmed with 26 kD T cell clone supernatants. Moreover, supernatants obtained after stimulation with phorbol myristate acetate were able to enhance the IgE production of a hybridoma B cell line (B48-14) producing a monoclonal IgE antibody, cytotoxic for the schistosomula. PMID:3498590

  5. Molecular cloning and characterization of recA-like gene from Schizosaccharomyces pombe

    International Nuclear Information System (INIS)

    Lee, J.S.; Kang, J.K.; Yoon, S.M.; Park, Y.; Yang, Y.K.; Kim, S.W.; Park, J.K.; Park, J.G.; Hong, S.H.; Park, S.D.

    1996-01-01

    We have previously purified and characterized a RecA-like protein from Schizosaccharomyces pombe (S. pombe). In the present study, we have cloned a gene encoding the RecA-like protein. The S. pombe recA-like gene was isolated by immunological screening of the expression library of S. pombe using anti-Escherichia coli (E. coli) RecA antibody as a probe. From 10(6) plaques screened, 6 putative clones were finally isolated. Five of the clones screened contained the same kinds of DNA inserts, as determined by crosshybridization analysis. Among the clones, TC-2 was selected for further studies. The pGEM3Zf(-)Delta 17 vector harboring the 4.3 kb DNA insert of TC-2 clone was capable of producing abeta-gal/RecA-like fusion protein, suggesting that the cloned gene encodes the RecA-like protein of S. pombe. It was also revealed by Southern hybridization analysis that the same DNA sequence as the cloned recA-like gene is located within the S. pombe chromosomal DNA. In addition, the cloned recA-like gene was transcribed into a 3.0 kb RNA transcript, as judged by Northern blot analysis. The level of the RNA transcript of recA-like gene was increased approximately 1.6 to 2.4-fold upon treatment with DNA damaging agents such as ultraviolet (UV)-light, methyl methanesulfonate (MMS), and mitomycin-C (MMC). This data suggests that the cloned S. pombe recA-like gene is slightly inducible to DNAdamage as in E. coli recA gene. These results suggest that an inducible repair mechanism analogous to that of E. coli may exist in fission yeast S. pombe

  6. Cloning and Expression of the PHA Synthase Gene From a Locally Isolated Chromobacterium sp. USM2

    Directory of Open Access Journals (Sweden)

    Bhubalan, K.

    2010-01-01

    Full Text Available Chromobacterium sp. USM2, a locally isolated bacterium was found to synthesize poly(3-hydroxybutyrate-co-3-hydroxyvalerate, P(3HB-co-3HV copolymer with high 3HV monomer composition. The PHA synthase gene was cloned and expressed in Cupriavidus necator PHB¯4 to investigate the possibilities of incorporating other monomer. The recombinant successfully incorporated 3-hydroxyhexanoate (3HHx monomer when fed with crude palm kernel oil (CPKO as the sole carbon source. Approximately 63 ± 2 wt% of P(3HB-co-3HHx copolymer with 4 mol% of 3HHx was synthesized from 5 g/L of oil after 48 h of cultivation. In addition, P(3HB-co-3HV-co-3HHx terpolymer with 9 mol% 3HV and 4 mol% 3HHx could be synthesized with a mixture of CPKO and sodium valerate. The presence of 3HV and 3HHx monomers in the copolymer and terpolymer was further confirmed with +H-NMR analysis. This locally isolated PHA synthase has demonstrated its ability to synthesize P(3HB-co-3HHx copolymer from a readily available and renewable carbon source; CPKO, without the addition of 3HHx precursors.

  7. Cloning and sequencing of a cellobiohydrolase gene from Trichoderma harzianum FP108

    Science.gov (United States)

    Patrick Guilfoile; Ron Burns; Zu-Yi Gu; Matt Amundson; Fu-Hsian Chang

    1999-01-01

    A cbbl cellobiohydrolase gene was cloned and sequenced from the fungus Trichoderrna harzianum FP108. The cloning was performed by PCR amplification of T. harzianum genomic DNA, using PCR primers whose sequence was based on the cbbl gene from Tricboderma reesei. The 3' end of the gene was isolated by inverse...

  8. Circulating nucleic acids damage DNA of healthy cells by integrating ...

    Indian Academy of Sciences (India)

    2015-02-04

    Feb 4, 2015 ... detected the presence of tens of thousands of human sequence reads in the recipient mouse cells. Genomic .... 2.7 Development of single-cell clones from DNAfs- ... DNA was isolated to generate whole genome libraries for.

  9. Isolation of oogenesis-specific genes transcribed in the germ-line of Calliphora erythrocephala and Drosophila melanogaster

    International Nuclear Information System (INIS)

    Tucker, M.A.

    1988-01-01

    Poly(A) + RNA from early or mid-stage ovarian follicles of C. erythrocephala was used to generate radiolabelled oogenesis-specific cDNA probes for screening the phage libraries. A cDNA probe made from mid-stage embryo poly(A) + RNA was used as the differential screening probe. Thus plaques hybridizing to the two oogenesis-specific probes but not the mid-stage embryo probe were selected as potentially containing oogenesis-specific genes. Two further rounds of screening were used to eliminate false positives and, after plaque purification, restriction digests of the remaining clones were screened by Southern blot hybridization to identify DNA fragments transcribed in an oogenesis-specific manner. In situ hybridization to sections of ovarian follicles has been used to determine the cell types within the follicles in which the various genes are expressed. Radiolabelled RNA probes for four of the C. erythrocephala oogenesis-specific clones and the two D. melanogaster clones have been hybridized to ovarian follicles. Further studies have been concentrated on the two germ-line transcribed, oogenesis-specific clones isolated from the D. melanogaster clone library. Detailed genetic mapping of the DA clone and of these mutations was performed to determine which mutations might represent the DA gene. cDNA clones have been isolated for the transcribed region of clone DA and have been used to further define the transcription unit from this region of the D. melanogaster genome

  10. Clonal profile, virulence and resistance of Staphylococcus aureus isolated from sheep milk

    Directory of Open Access Journals (Sweden)

    Katheryne Benini Martins

    2015-06-01

    Full Text Available The objective of this study was to characterize the clonal profile, virulence factors and antimicrobial resistance, particularly oxacillin resistance, of Staphylococcus aureus isolated from sheep milk. Milk samples were collected from all teats for the California Mastitis Test (CMT, somatic cell count, identification of S. aureus, investigation in these strains of genes encoding toxins (sea, seb, sec, sed, tst, biofilm (icaA, icaC, icaD, bap, leukocidin (luk-PV oxacillin resistance by mecA gene detection and susceptibility testing (12 antibiotics. Messenger RNA expression was evaluated by RT-PCR in isolates carrying toxin and biofilm genes. Biofilm formation was also evaluated phenotypically by adherence to polystyrene plates. The clonal profile of S. aureus was investigated by pulsed-field gel electrophoresis. A total of 473 milk samples were collected from 242 animals on three farms and 20 S. aureus strains were isolated and none carried the mecA gene. The two sec gene-positive isolates and the isolates carrying the tst and luk-PV genes were positive by RT-PCR. Staphylococcus aureus isolated from the three flocks studied showed high susceptibility to the drugs tested and none was biofilm producer, indicating that biofilm formation was not a virulence factor causing infection by these strains. The typing of 17 S. aureus isolates revealed the presence of a common clone on the three farms studied, and the presence and expression of the sec and tst genes in one strain of this clone suggest the possible acquisition of virulence genes by this clone, a fact that is important for animal health and food hygiene.

  11. Alu polymerase chain reaction: A method for rapid isolation of human-specific sequences from complex DNA sources

    International Nuclear Information System (INIS)

    Nelson, D.L.; Ledbetter, S.A.; Corbo, L.; Victoria, M.F.; Ramirez-Solis, R.; Webster, T.D.; Ledbetter, D.H.; Caskey, C.T.

    1989-01-01

    Current efforts to map the human genome are focused on individual chromosomes or smaller regions and frequently rely on the use of somatic cell hybrids. The authors report the application of the polymerase chain reaction to direct amplification of human DNA from hybrid cells containing regions of the human genome in rodent cell backgrounds using primers directed to the human Alu repeat element. They demonstrate Alu-directed amplification of a fragment of the human HPRT gene from both hybrid cell and cloned DNA and identify through sequence analysis the Alu repeats involved in this amplification. They also demonstrate the application of this technique to identify the chromosomal locations of large fragments of the human X chromosome cloned in a yeast artificial chromosome and the general applicability of the method to the preparation of DNA probes from cloned human sequences. The technique allows rapid gene mapping and provides a simple method for the isolation and analysis of specific chromosomal regions

  12. FastCloning: a highly simplified, purification-free, sequence- and ligation-independent PCR cloning method

    Directory of Open Access Journals (Sweden)

    Lu Jia

    2011-10-01

    Full Text Available Abstract Background Although a variety of methods and expensive kits are available, molecular cloning can be a time-consuming and frustrating process. Results Here we report a highly simplified, reliable, and efficient PCR-based cloning technique to insert any DNA fragment into a plasmid vector or into a gene (cDNA in a vector at any desired position. With this method, the vector and insert are PCR amplified separately, with only 18 cycles, using a high fidelity DNA polymerase. The amplified insert has the ends with ~16-base overlapping with the ends of the amplified vector. After DpnI digestion of the mixture of the amplified vector and insert to eliminate the DNA templates used in PCR reactions, the mixture is directly transformed into competent E. coli cells to obtain the desired clones. This technique has many advantages over other cloning methods. First, it does not need gel purification of the PCR product or linearized vector. Second, there is no need of any cloning kit or specialized enzyme for cloning. Furthermore, with reduced number of PCR cycles, it also decreases the chance of random mutations. In addition, this method is highly effective and reproducible. Finally, since this cloning method is also sequence independent, we demonstrated that it can be used for chimera construction, insertion, and multiple mutations spanning a stretch of DNA up to 120 bp. Conclusion Our FastCloning technique provides a very simple, effective, reliable, and versatile tool for molecular cloning, chimera construction, insertion of any DNA sequences of interest and also for multiple mutations in a short stretch of a cDNA.

  13. Complete dissection of the Hb(64-76) determinant using T helper 1, T helper 2 clones, and T cell hybridomas

    DEFF Research Database (Denmark)

    Evavold, B D; Williams, S G; Hsu, B L

    1992-01-01

    We have generated cloned Th1 cells, Th2 cells, and T cell hybridomas specific for the single immunogenic peptide from the beta-chain of murine hemoglobin (Hb(64-76)). The availability of these various types of T cells provided us an unique opportunity to examine and dissect the T cell response...... to an immunogenic peptide. A panel of altered Hb peptides was made by replacing each amino acid in the Hb peptide (positions 64-76) with a conservative amino acid substitution or an alanine. Although none of the eleven T cell clones and hybridomas tested exhibited the same pattern of reactivity to the substituted...... Hb peptides, some general features were identified for all T cell responses. The primary T cell contact residue of Hb(64-76) was shown to be asparagine 72. For every Hb(64-76) specific T cell, no activation was observed using a peptide containing the conservative substitution of a glutamine...

  14. Infection of human and non-human cells by a highly fusogenic primary CD4-independent HIV-1 isolate with a truncated envelope cytoplasmic tail

    International Nuclear Information System (INIS)

    Saha, Kunal; Yan Hui; Nelson, Julie A.E.; Zerhouni-Layachi, Bouchra

    2005-01-01

    Truncation of the envelope cytoplasmic tail has enabled FIV, SIV, and some laboratory HIV-1 strains to acquire broader cellular tropism and enhanced fusogenicity. Here we have characterized a primary CD4-independent HIV-1 isolate (92UG046-T8) with a truncated cytoplasmic tail that was able to infect and induce syncytia in primary lymphocytes from human, chimpanzee, and monkey, as well as CD4-negative cell lines from human and monkey. Increased syncytia were also noticeable with 293 cells expressing the cloned envelope from the 92UG046-T8 isolate suggesting envelope-mediated cellular fusion. Except pooled serum from HIV-1-infected individuals, monoclonal anti-envelope antibodies or antibodies/antagonists against CD4, CXCR4, and CCR5 were not able to prevent infection by the 92UG046-T8 isolate. This is the first report showing a primary HIV-1 variant with truncated cytoplasmic tail which is highly fusogenic and can infect a broad range of cells from human and non-human origins. In vivo evolution of similar HIV-1 mutants may have important implications in AIDS pathogenesis

  15. Social behavior and kin discrimination in a mixed group of cloned and non cloned heifers (Bos taurus).

    Science.gov (United States)

    Coulon, M; Baudoin, C; Abdi, H; Heyman, Y; Deputte, B L

    2010-12-01

    For more than ten years, reproductive biotechnologies using somatic cell nuclear transfer have made possible the production of cloned animals in various domestic and laboratory species. The influence of the cloning process on offspring characteristics has been studied in various developmental aspects, however, it has not yet been documented in detail for behavioral traits. Behavioral studies of cloned animals have failed to show clear inter-individual differences associated with the cloning process. Preliminary results showed that clones favor each other's company. Preferential social interactions were observed among cloned heifers from the same donor in a mixed herd that also included cloned heifers and control heifers produced by artificial insemination (AI). These results suggest behavioral differences between cloned and non-cloned animals and similarities between clones from the same donor. The aim of the present study was to replicate and to extend these previous results and to study behavioral and cognitive mechanisms of this preferential grouping. We studied a group composed of five cloned heifers derived from the same donor cow, two cloned heifers derived from another donor cow, and AI heifers. Cloned heifers from the same donor were more spatially associated and interacted more between themselves than with heifers derived from another donor or with the AI individuals. This pattern indicates a possible kin discrimination in clones. To study this process, we performed an experiment (using an instrumental conditioning procedure with food reward) of visual discrimination between images of heads of familiar heifers, either related to the subjects or not. The results showed that all subjects (AI and cloned heifers) discriminated between images of familiar cloned heifers produced from the same donor and images of familiar unrelated heifers. Cattle discriminated well between images and used morphological similarities characteristic of cloned related heifers. Our

  16. Technologies for Single-Cell Isolation

    Science.gov (United States)

    Gross, Andre; Schoendube, Jonas; Zimmermann, Stefan; Steeb, Maximilian; Zengerle, Roland; Koltay, Peter

    2015-01-01

    The handling of single cells is of great importance in applications such as cell line development or single-cell analysis, e.g., for cancer research or for emerging diagnostic methods. This review provides an overview of technologies that are currently used or in development to isolate single cells for subsequent single-cell analysis. Data from a dedicated online market survey conducted to identify the most relevant technologies, presented here for the first time, shows that FACS (fluorescence activated cell sorting) respectively Flow cytometry (33% usage), laser microdissection (17%), manual cell picking (17%), random seeding/dilution (15%), and microfluidics/lab-on-a-chip devices (12%) are currently the most frequently used technologies. These most prominent technologies are described in detail and key performance factors are discussed. The survey data indicates a further increasing interest in single-cell isolation tools for the coming years. Additionally, a worldwide patent search was performed to screen for emerging technologies that might become relevant in the future. In total 179 patents were found, out of which 25 were evaluated by screening the title and abstract to be relevant to the field. PMID:26213926

  17. Technologies for Single-Cell Isolation

    Directory of Open Access Journals (Sweden)

    Andre Gross

    2015-07-01

    Full Text Available The handling of single cells is of great importance in applications such as cell line development or single-cell analysis, e.g., for cancer research or for emerging diagnostic methods. This review provides an overview of technologies that are currently used or in development to isolate single cells for subsequent single-cell analysis. Data from a dedicated online market survey conducted to identify the most relevant technologies, presented here for the first time, shows that FACS (fluorescence activated cell sorting respectively Flow cytometry (33% usage, laser microdissection (17%, manual cell picking (17%, random seeding/dilution (15%, and microfluidics/lab-on-a-chip devices (12% are currently the most frequently used technologies. These most prominent technologies are described in detail and key performance factors are discussed. The survey data indicates a further increasing interest in single-cell isolation tools for the coming years. Additionally, a worldwide patent search was performed to screen for emerging technologies that might become relevant in the future. In total 179 patents were found, out of which 25 were evaluated by screening the title and abstract to be relevant to the field.

  18. Technologies for Single-Cell Isolation.

    Science.gov (United States)

    Gross, Andre; Schoendube, Jonas; Zimmermann, Stefan; Steeb, Maximilian; Zengerle, Roland; Koltay, Peter

    2015-07-24

    The handling of single cells is of great importance in applications such as cell line development or single-cell analysis, e.g., for cancer research or for emerging diagnostic methods. This review provides an overview of technologies that are currently used or in development to isolate single cells for subsequent single-cell analysis. Data from a dedicated online market survey conducted to identify the most relevant technologies, presented here for the first time, shows that FACS (fluorescence activated cell sorting) respectively Flow cytometry (33% usage), laser microdissection (17%), manual cell picking (17%), random seeding/dilution (15%), and microfluidics/lab-on-a-chip devices (12%) are currently the most frequently used technologies. These most prominent technologies are described in detail and key performance factors are discussed. The survey data indicates a further increasing interest in single-cell isolation tools for the coming years. Additionally, a worldwide patent search was performed to screen for emerging technologies that might become relevant in the future. In total 179 patents were found, out of which 25 were evaluated by screening the title and abstract to be relevant to the field.

  19. Cloning of the unculturable parasite Pasteuria ramosa and its Daphnia host reveals extreme genotype-genotype interactions.

    Science.gov (United States)

    Luijckx, Pepijn; Ben-Ami, Frida; Mouton, Laurence; Du Pasquier, Louis; Ebert, Dieter

    2011-02-01

    The degree of specificity in host-parasite interactions has important implications for ecology and evolution. Unfortunately, specificity can be difficult to determine when parasites cannot be cultured. In such cases, studies often use isolates of unknown genetic composition, which may lead to an underestimation of specificity. We obtained the first clones of the unculturable bacterium Pasteuria ramosa, a parasite of Daphnia magna. Clonal genotypes of the parasite exhibited much more specific interactions with host genotypes than previous studies using isolates. Clones of P. ramosa infected fewer D. magna genotypes than isolates and host clones were either fully susceptible or fully resistant to the parasite. Our finding enhances our understanding of the evolution of virulence and coevolutionary dynamics in this system. We recommend caution when using P. ramosa isolates as the presence of multiple genotypes may influence the outcome and interpretation of some experiments. © 2010 Blackwell Publishing Ltd/CNRS.

  20. Characterization of the Brazilian endemic clone of methicillin-resistant Staphylococcus aureus (MRSA from hospitals throughout Brazil

    Directory of Open Access Journals (Sweden)

    Geraldo A. Oliveira

    Full Text Available The objective of this study was to characterize patterns of the Brazilian endemic clone of methicillin-resistant Staphylococcus aureus (MRSA from hospitals throughout Brazil. We studied 83 MRSA strains isolated from patients hospitalized in 27 public and private hospitals in 19 cities located in 14 Brazilian states from September, 1995, to June, 1997. The MRSA strains were typed using antibiograms, bacteriophage typing and pulsed field gel electrophoresis (PFGE. The analysis of genomic DNA by PFGE showed that 65 isolates presented the same PFGE pattern. This pattern was present in all of the hospitals studied indicating the presence of an endemic MRSA clone widely disseminated throughout Brazilian hospitals (BEC. All isolates belonging to the BEC proved to be resistant to ciprofloxacin, erythromycin, lincomycin, trimethoprim-sulphamethoxazole, and tetracycline. Variable susceptibility to these drugs was found only in isolates belonging to clones other than the BEC. The results show that, among MRSA, the BEC is common in Brazil. The best method for mapping changes in the frequency of this clone among MRSA is pulsed field gel electrophoresis. Use of molecular mapping is an important tool for monitoring the spread of potentially dangerous microbes.

  1. Human catechol-O-methyltransferase: Cloning and expression of the membrane-associated form

    International Nuclear Information System (INIS)

    Bertocci, B.; Miggiano, V.; Da Prada, M.; Dembic, Z.; Lahm, H.W.; Malherbe, P.

    1991-01-01

    A cDNA clone for human catechol-O-methyltransferase was isolated from a human hepatoma cell line (Hep G2) cDNA library by hybridization screening with a porcine cDNA probe. The cDNA clone was sequenced and found to have an insert of 1226 nucleotides. The deduced primary structure of hCOMT is composed of 271 amino acid residues with the predicted molecular mass of 30 kDa. At its N terminus it has a hydrophobic segment of 21 amino acid residues that may be responsible for insertion of hCOMT into the endoplasmic reticulum membrane. The primary structure of hCOMT exhibits high homology to the porcine partial cDNA sequence (93%). The deduced amino acid sequence contains two tryptic peptide sequences (T-22, T-33) found in porcine liver catechol-O-methyltransferase (CEMT). The coding region of hCOMT cDNA was placed under the control of the cytomegalovirus promoter to transfect human kidney 293 cells. The recombinant hCOMT was shown by immunoblot analysis to be mainly associated with the membrane fraction. RNA blot analysis revealed one COMT mRNA transcript of 1.4 kilobases in Hep G2 poly(A) + RNA

  2. Temperature-Sensitive Mutants of Mouse Hepatitis Virus Strain A59: Isolation, Characterization and Neuropathogenic Properties.

    NARCIS (Netherlands)

    M.J.M. Koolen (Marck); A.D.M.E. Osterhaus (Albert); G. van Steenis (Bert); M.C. Horzinek; B.A.M. van der Zeijst (Ben)

    1983-01-01

    textabstractTwenty 5-fluorouracil-induced temperature-sensitive (ts) mutants of mouse hepatitis virus strain A59 were isolated from 1284 virus clones. Mutants were preselected on the basis of their inability to induce syncytia in infected cells at the restrictive temperature (40 degrees) vs the

  3. Emergence and dissemination of a linezolid-resistant Staphylococcus capitis clone in Europe.

    Science.gov (United States)

    Butin, M; Martins-Simões, P; Pichon, B; Leyssene, D; Bordes-Couecou, S; Meugnier, H; Rouard, C; Lemaitre, N; Schramm, F; Kearns, A; Spiliopoulou, I; Hyyryläinen, H-L; Dumitrescu, O; Vandenesch, F; Dupieux, C; Laurent, F

    2017-04-01

    We investigated the epidemiological, clinical, microbiological and genetic characteristics of linezolid-resistant (LZR) Staphylococcus capitis isolates from French ICUs, and compared them with LZR S. capitis isolates from other European countries. All LZR isolates were subjected to antimicrobial susceptibility testing (AST) and the presence of cfr and optrA genes as well as mutations in the 23S rRNA and ribosomal proteins were investigated using specific PCR with sequencing. The genetic relationship between isolates was investigated using PFGE and WGS. Epidemiological data concerning LZR S. capitis were collected retrospectively in French microbiology laboratories. Twenty-one LZR isolates were studied: 9 from France, 11 from Greece and 1 from Finland. All were resistant to methicillin and aminoglycosides. In addition, this unusual AST profile was identified in S. capitis isolates from seven French hospitals, and represented up to 12% of the S. capitis isolates in one centre. A G2576T mutation in 23S rRNA was identified in all isolates; cfr and optrA genes were absent. All isolates belonged to the same clone on the basis of their PFGE profiles, whatever their geographical origin. WGS found at most 212 SNPs between core genomes of the LZR isolates. We identified and characterized an LZR S. capitis clone disseminated in three European countries, harbouring the same multiple resistance and a G2576T mutation in the 23S rRNA. The possible unrecognized wider distribution of this clone, belonging to a species classically regarded as a low-virulence skin colonizer, is of major concern not least because of the increasing use of oxazolidinones. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. Mesenchymal stem cells isolated from peripheral blood and umbilical cord Wharton’s jelly

    Directory of Open Access Journals (Sweden)

    Trivanović Drenka

    2013-01-01

    Full Text Available Introduction. Mesenchymal stem cells (MSCs are a promising tool for regenerative medicine, but due to the heterogeneity of their populations, different sources and isolation techniques, the characteristics defining MSCs are inconsistent. Objective. The aim of this study was to compare the characteristics of MSCs derived from two different human tissues: peripheral blood (PB-MSCs and umbilical cord Wharton’s Jelly (UC-MSCs. Methods. The PB-MSC and UC-MSC were isolated by adherence to plastic after gradient-density separation or an explant culture method, respectively, and compared regarding their morphology, clonogenic efficiency, proliferating rates, immunophenotype and differentiation potential. Results. MSCs derived from both sources exhibit similar morphology, proliferation capacity and multilineage (osteogenic, chondrogenic, adipogenic and myogenic differentiation potential. Differences were observed in the clonogenic capacity and the immunophenotype, since UC-MSCs showed higher CFU-F (colony-forming units-fibroblastic cloning efficiency, as well as higher embryonic markers (Nanog, Sox2, SSEA4 expression. When additional surface antigens were analyzed by flow cytometry (CD44, CD90, CD105, CD33, CD34, CD45, CD11b, CD235a or immunofluorescent labeling (vimentin, STRO-1 and α-smooth muscle actin, most appeared to have similar epitope profiles irrespective of MSC source. Conclusion. The results obtained demonstrated that both MSCs represent good alternative sources of adult MSCs that could be used in cell therapy applications. [Projekat Ministarstva nauke Republike Srbije, br. 175062

  5. Heterogeneity in cytokine profiles of Babesia bovis-specific bovine CD4+ T cells clones activated in vitro.

    OpenAIRE

    Brown, W C; Woods, V M; Dobbelaere, D A; Logan, K S

    1993-01-01

    The central role of T cells in the immune response against hemoprotozoan parasites, both as helper cells for T cell-dependent antibody production and as effector cells acting on intracellular parasites through the elaboration of cytokines, has prompted an investigation of the bovine cellular immune response against Babesia bovis antigens. CD4+ T helper (Th) cell clones generated from four B. bovis-immune cattle by in vitro stimulation with a soluble or membrane-associated merozoite antigen we...

  6. Evaluation of the efficiency and utility of recombinant enzyme-free seamless DNA cloning methods

    Directory of Open Access Journals (Sweden)

    Ken Motohashi

    2017-03-01

    Full Text Available Simple and low-cost recombinant enzyme-free seamless DNA cloning methods have recently become available. In vivo Escherichia coli cloning (iVEC can directly transform a mixture of insert and vector DNA fragments into E. coli, which are ligated by endogenous homologous recombination activity in the cells. Seamless ligation cloning extract (SLiCE cloning uses the endogenous recombination activity of E. coli cellular extracts in vitro to ligate insert and vector DNA fragments. An evaluation of the efficiency and utility of these methods is important in deciding the adoption of a seamless cloning method as a useful tool. In this study, both seamless cloning methods incorporated inserting DNA fragments into linearized DNA vectors through short (15–39 bp end homology regions. However, colony formation was 30–60-fold higher with SLiCE cloning in end homology regions between 15 and 29 bp than with the iVEC method using DH5α competent cells. E. coli AQ3625 strains, which harbor a sbcA gene mutation that activates the RecE homologous recombination pathway, can be used to efficiently ligate insert and vector DNA fragments with short-end homology regions in vivo. Using AQ3625 competent cells in the iVEC method improved the rate of colony formation, but the efficiency and accuracy of SLiCE cloning were still higher. In addition, the efficiency of seamless cloning methods depends on the intrinsic competency of E. coli cells. The competency of chemically competent AQ3625 cells was lower than that of competent DH5α cells, in all cases of chemically competent cell preparations using the three different methods. Moreover, SLiCE cloning permits the use of both homemade and commercially available competent cells because it can use general E. coli recA− strains such as DH5α as host cells for transformation. Therefore, between the two methods, SLiCE cloning provides both higher efficiency and better utility than the iVEC method for seamless DNA plasmid

  7. In silico cloning and B/T cell epitope prediction of triosephosphate isomerase from Echinococcus granulosus.

    Science.gov (United States)

    Wang, Fen; Ye, Bin

    2016-10-01

    Cystic echinococcosis is a worldwide zoonosis caused by Echinococcus granulosus. Because the methods of diagnosis and treatment for cystic echinococcosis were limited, it is still necessary to screen target proteins for the development of new anti-hydatidosis vaccine. In this study, the triosephosphate isomerase gene of E. granulosus was in silico cloned. The B cell and T cell epitopes were predicted by bioinformatics methods. The cDNA sequence of EgTIM was composition of 1094 base pairs, with an open reading frame of 753 base pairs. The deduced amino acid sequences were composed of 250 amino acids. Five cross-reactive epitopes, locating on 21aa-35aa, 43aa-57aa, 94aa-107aa, 115-129aa, and 164aa-183aa, could be expected to serve as candidate epitopes in the development of vaccine against E. granulosus. These results could provide bases for gene cloning, recombinant expression, and the designation of anti-hydatidosis vaccine.

  8. Assessing cell fusion and cytokinesis failure as mechanisms of clone 9 hepatocyte multinucleation in vitro.

    Science.gov (United States)

    Simic, Damir; Euler, Catherine; Thurby, Christina; Peden, Mike; Tannehill-Gregg, Sarah; Bunch, Todd; Sanderson, Thomas; Van Vleet, Terry

    2012-08-01

    In this in vitro model of hepatocyte multinucleation, separate cultures of rat Clone 9 cells are labeled with either red or green cell tracker dyes (Red Cell Tracker CMPTX or Vybrant CFDA SE Cell Tracer), plated together in mixed-color colonies, and treated with positive or negative control agents for 4 days. The fluorescent dyes become cell-impermeant after entering cells and are not transferred to adjacent cells in a population, but are inherited by daughter cells after fusion. The mixed-color cultures are then evaluated microscopically for multinucleation and analysis of the underlying mechanism (cell fusion/cytokinesis). Multinucleated cells containing only one dye have undergone cytokinesis failure, whereas dual-labeled multinucleated cells have resulted from fusion. © 2012 by John Wiley & Sons, Inc.

  9. Cell colony formation induced by Xenopus egg extract as a marker for improvement of cloned blastocyst formation in pig

    DEFF Research Database (Denmark)

    Liu, Ying; Østrup, Olga; Li, Juan

    2011-01-01

    method based on the colony formation of cells after extract treatment, and subsequent in vitro cloning efficiency using treated cells as chromatin donors. Porcine fetal fibroblasts were treated with each batch of extract, and cultured in embryonic stem cell (ES) medium for 12 days. The number of forming...

  10. Construction of an infectious plasmid clone of Muscovy duck parvovirus by TA cloning and creation of a partially attenuated strain.

    Science.gov (United States)

    Yen, T-Y; Li, K-P; Ou, S-C; Shien, J-H; Lu, H-M; Chang, P-C

    2015-01-01

    Muscovy duck parvovirus (MDPV) infection is a highly contagious and fatal disease of Muscovy ducklings. The infectious clone methodology is a valuable tool to study the pathogenic mechanisms of viruses, but no infectious clone of MDPV is yet available. In this study, a plasmid clone containing the full-length genome of MDPV was constructed using the TA cloning methodology. This MDPV clone was found to be infectious after transfection of primary Muscovy duck embryo fibroblast cells and passage in embryonated Muscovy duck eggs. Site-directed mutagenesis showed that the K75N mutation in the VP1 protein of MDPV resulted in the partial attenuation of the virus. The availability of an MDPV infectious clone can facilitate investigation of the pathogenic mechanisms of MDPV and development of vaccines against diseases caused by MDPV.

  11. Assay of mouse-cell clones for retrovirus p30 protein by use of an automated solid-state radioimmunoassay

    International Nuclear Information System (INIS)

    Kennel, S.J.; Tnnant, R.W.

    1979-01-01

    A solid-state radioimmunoassay system has been developed that is useful for automated analysis of samples in microtiter plates. Assays for interspecies and type-specific antigenic determinants of the C-type retrovirus protein, p30, have been used to identify clones of cells producing this protein. This method allows testing of at least 1000 clones a day, making it useful for studies of frequencies of virus protein induction, defective virus production, and formation of recombinant viruses

  12. Transposons and integrons in colistin-resistant clones of Klebsiella pneumoniae and Acinetobacter baumannii with epidemic or sporadic behaviour.

    Science.gov (United States)

    Arduino, Sonia M; Quiroga, María Paula; Ramírez, María Soledad; Merkier, Andrea Karina; Errecalde, Laura; Di Martino, Ana; Smayevsky, Jorgelina; Kaufman, Sara; Centrón, Daniela

    2012-10-01

    Multiple transposons, integrons and carbapenemases were found in Klebsiella pneumoniae colistin-resistant isolates as well as a genomic resistance island of the AbaR type in Acinetobacter baumannii colistin-resistant isolates from different hospitals from Buenos Aires City. PFGE analysis showed a polyclonal dissemination of antimicrobial resistance mechanisms among K. pneumoniae isolates, while in A. baumannii isolates the epidemic clone 1 from South America was found. Resistance determinants associated with horizontal gene transfer are contributing to the evolution to pandrug resistance in both epidemic and sporadic clones.

  13. Molecular and Biological Characterization of an Isolate of Cucumber mosaic virus from Glycine soja by Generating its Infectious Full-genome cDNA Clones

    Directory of Open Access Journals (Sweden)

    Mi Sa Vo Phan

    2014-06-01

    Full Text Available Molecular and biological characteristics of an isolate of Cucumber mosaic virus (CMV from Glycine soja (wild soybean, named as CMV-209, was examined in this study. Comparison of nucleotide sequences and phylogenetic analyses of CMV-209 with the other CMV strains revealed that CMV-209 belonged to CMV subgroup I. However, CMV-209 showed some genetic distance from the CMV strains assigned to subgroup IA or subgroup IB. Infectious full-genome cDNA clones of CMV-209 were generated under the control of the Cauliflower mosaic virus 35S promoter. Infectivity of the CMV-209 clones was evaluated in Nicotiana benthamiana and various legume species. Our assays revealed that CMV-209 could systemically infect Glycine soja (wild soybean and Pisum sativum (pea as well as N. benthamiana, but not the other legume species.

  14. A new trilocus sequence-based multiplex-PCR to detect major Acinetobacter baumannii clones.

    Science.gov (United States)

    Martins, Natacha; Picão, Renata Cristina; Cerqueira-Alves, Morgana; Uehara, Aline; Barbosa, Lívia Carvalho; Riley, Lee W; Moreira, Beatriz Meurer

    2016-08-01

    A collection of 163 Acinetobacter baumannii isolates detected in a large Brazilian hospital, was potentially related with the dissemination of four clonal complexes (CC): 113/79, 103/15, 109/1 and 110/25, defined by University of Oxford/Institut Pasteur multilocus sequence typing (MLST) schemes. The urge of a simple multiplex-PCR scheme to specify these clones has motivated the present study. The established trilocus sequence-based typing (3LST, for ompA, csuE and blaOXA-51-like genes) multiplex-PCR rapidly identifies international clones I (CC109/1), II (CC118/2) and III (CC187/3). Thus, the system detects only one (CC109/1) out of four main CC in Brazil. We aimed to develop an alternative multiplex-PCR scheme to detect these clones, known to be present additionally in Africa, Asia, Europe, USA and South America. MLST, performed in the present study to complement typing our whole collection of isolates, confirmed that all isolates belonged to the same four CC detected previously. When typed by 3LST-based multiplex-PCR, only 12% of the 163 isolates were classified into groups. By comparative sequence analysis of ompA, csuE and blaOXA-51-like genes, a set of eight primers was designed for an alternative multiplex-PCR to distinguish the five CC 113/79, 103/15, 109/1, 110/25 and 118/2. Study isolates and one CC118/2 isolate were blind-tested with the new alternative PCR scheme; all were correctly clustered in groups of the corresponding CC. The new multiplex-PCR, with the advantage of fitting in a single reaction, detects five leading A. baumannii clones and could help preventing the spread in healthcare settings. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Antigen-specific cytotoxic T cell and antigen-specific proliferating T cell clones can be induced to cytolytic activity by monoclonal antibodies against T3

    NARCIS (Netherlands)

    Spits, H.; Yssel, H.; Leeuwenberg, J.; de Vries, J. E.

    1985-01-01

    T3 is a human differentiation antigen expressed exclusively on mature T cells. In this study it is shown that anti-T3 monoclonal antibodies, in addition to their capacity to induce T cells to proliferate, are able to induce antigen-specific cytotoxic T lymphocyte clones to mediate antigen

  16. CD4+ T-cell clones obtained from cattle chronically infected with Fasciola hepatica and specific for adult worm antigen express both unrestricted and Th2 cytokine profiles.

    Science.gov (United States)

    Brown, W C; Davis, W C; Dobbelaere, D A; Rice-Ficht, A C

    1994-01-01

    The well-established importance of helper T (Th)-cell subsets in immunity and immunoregulation of many experimental helminth infections prompted a detailed study of the cellular immune response against Fasciola hepatica in the natural bovine host. T-cell lines established from two cattle infected with F. hepatica were characterized for the expression of T-cell surface markers and proliferative responses against F. hepatica adult worm antigen. Parasite-specific T-cell lines contained a mixture of CD4+, CD8+, and gamma/delta T-cell-receptor-bearing T cells. However, cell lines containing either fewer than 10% CD8+ T cells or depleted of gamma/delta T cells proliferated vigorously against F. hepatica antigen, indicating that these T-cell subsets are not required for proliferative responses in vitro. Seventeen F. hepatica-specific CD4+ Th-cell clones were examined for cytokine expression following concanavalin A stimulation. Biological assays to measure interleukin-2 (IL-2) or IL-4, gamma interferon (IFN-gamma), and tumor necrosis factor and Northern (RNA) blot analysis to verify the expression of IL-2, IL-4, and IFN-gamma revealed that the Th-cell clones expressed a spectrum of cytokine profiles. Several Th-cell clones were identified as Th2 cells by the strong expression of IL-4 but little or no IL-2 or IFN-gamma mRNA. The majority of Th-cell clones were classified as Th0 cells by the expression of either all three cytokines or combinations of IL-2 and IL-4 or IL-4 and IFN-gamma. No Th1-cell clones were obtained. All of the Th-cell clones expressed a typical memory cell surface phenotype, characterized as CD45Rlow, and all expressed the lymph node homing receptor (L selectin). These results are the first to describe cytokine responses of F. hepatica-specific T cells obtained from infected cattle and extend our previous analysis of Th0 and Th1 cells from cattle immune to Babesia bovis (W. C. Brown, V. M. Woods, D. A. E. Dobbelaere, and K. S. Logan, Infect. Immun. 61

  17. The science and technology of farm animal cloning

    DEFF Research Database (Denmark)

    Gjerris, Mickey; Vajta, Gábor

    , goats, horses, cats, etc. have been cloned with the somatic cell nuclear transfer technique. Although the technology still has relatively low success rates and there seems to be substantial problems with the welfare of some of the cloned animals, cloning is used both within basic research...... include the production of genetically identical animals for research purposes, and also the creation of genetically modified animals. In the agricultural sector, cloning can be used as a tool within farm animal breeding. We do not intend to give an exhaustive review of the all the literature available...