GLORIA

GEOMAR Library Ocean Research Information Access

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
  • 1
    In: Laboratory Investigation, Elsevier BV, Vol. 97, No. 10 ( 2017-10), p. 1218-1224
    Materialart: Online-Ressource
    ISSN: 0023-6837
    RVK:
    Sprache: Englisch
    Verlag: Elsevier BV
    Publikationsdatum: 2017
    ZDB Id: 2041329-4
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 2
    In: Blood, American Society of Hematology, Vol. 108, No. 11 ( 2006-11-16), p. 454-454
    Kurzfassung: Gene correction is an attractive strategy for gene therapy since it allows the corrected gene to remain regulated within its native genome location. We have explored gene correction of murine severe combined immunodeficiency (SCID) with single-stranded DNA oligonucleotides (SSO). Murine SCID is characterized by severe T- and B-cell lymphopenia and is caused by a point mutation in the DNA protein kinase subunit (DNA-PK). To correct the mutant missense sequence (T to A substitution), a silent mutation was introduced by synthesizing the SSO non-transcribed sequence (45 bp) surrounding the site of the SCID mutation and replacing the T nucleotide with a C nucleotide to permit production of wild-type (wt) DNA-PK protein. Since the fetus is potentially an ideal permissive environment for gene correction due to the high proliferative rate of its tissues, SSO were injected in utero either directly into the liver of the fetus or transplacentally (via hydrodynamic infusion to the pregnant dam). E15/16 BALB/c-SCID recipients (N = 78) were injected with SSO (20 mcg/fetus). Twenty nine mice survived to term and, when evaluated by peripheral blood (PB) FACS at 15–30 weeks of life, 11 had significant phenotypic evidence of immune restoration defined as ≥ 2% CD4+ or CD8+ T cells: 6 had both CD4+ and CD8+ T cells, 2 had CD4+ cells only and 3 had CD8+ T cells only. The highest level of CD4+ cells seen was 9%, the highest level of CD8+ cells was 2% and both had TCR rearrangement and 27% and 15% genotypic correction of the mutated bp by quantitative pyrosequencing (PSQ) of DNA isolated from whole blood. Since placental membranes are permeable to some molecules, SSO were hydrodynamically delivered to pregnant BALB/c-SCID dams (100 mcg). Two of 8 evaluable mice injected on day E5/6 had significant numbers of T cells, one of which had 20% CD8+ with 3% CD4+ cells at 13 weeks of life, and PSQ showed a 13% correction rate. Sixteen offspring injected at E13/14 were analyzed: 2 had 4% and 5% CD4+ cells and the latter also had 6% of CD8+ cells with PSQ correction rates of 22% and 11%, respectively. Of 40 mice evaluated after transplacental injections at age E15/16, 9 had & gt;2% CD4+ or CD8+cells. The four with the highest T cell count had a genotypic correction of 12–25% of wt levels. Notably, littermates with no phenotypic correction had no evidence of gene correction at the DNA-PK mutation site. However, in all immune-restored animals that were analyzed for gene correction, (2/78 after in utero; 7/64 after transplacental delivery) an A to T rather than the anticipated A to C correction occurred. This is consistent with the hypothesis that SSO stimulated homologous recombination with a preferred utilization of the endogenous T rather than the exogenous C due to preferential pairing of two pyrimidines (A with T) than pyrimidine with purine (A with C). In summary, we show that SSO therapy for correction of DNA-PK mutation is possible when SSO are injected in utero at late gestation or are hydrodynamically delivered to the pregnant dam. These findings also suggest that while DNA homology around the mutation site is necessary for correction, the wt nucleotide is favored by the endogenous DNA repair pathway.
    Materialart: Online-Ressource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Sprache: Englisch
    Verlag: American Society of Hematology
    Publikationsdatum: 2006
    ZDB Id: 1468538-3
    ZDB Id: 80069-7
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 3
    In: Molecular Therapy, Elsevier BV, Vol. 19, No. 3 ( 2011-03), p. 450-460
    Materialart: Online-Ressource
    ISSN: 1525-0016
    Sprache: Englisch
    Verlag: Elsevier BV
    Publikationsdatum: 2011
    ZDB Id: 2001818-6
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 4
    Online-Ressource
    Online-Ressource
    The American Association of Immunologists ; 2018
    In:  The Journal of Immunology Vol. 201, No. 11 ( 2018-12-01), p. 3320-3328
    In: The Journal of Immunology, The American Association of Immunologists, Vol. 201, No. 11 ( 2018-12-01), p. 3320-3328
    Kurzfassung: Age-related thymic involution is characterized by a decrease in thymic epithelial cell (TEC) number and function parallel to a disruption in their spatial organization, resulting in defective thymocyte development and proliferation as well as peripheral T cell dysfunction. Deficiency of Klotho, an antiaging gene and modifier of fibroblast growth factor signaling, causes premature aging. To investigate the role of Klotho in accelerated age-dependent thymic involution, we conducted a comprehensive analysis of thymopoiesis and peripheral T cell homeostasis using Klotho-deficient (Kl/Kl) mice. At 8 wk of age, Kl/Kl mice displayed a severe reduction in the number of thymocytes (10–100-fold reduction), especially CD4 and CD8 double-positive cells, and a reduction of both cortical and medullary TECs. To address a cell-autonomous role for Klotho in TEC biology, we implanted neonatal thymi from Klotho-deficient and -sufficient mice into athymic hosts. Kl/Kl thymus grafts supported thymopoiesis equivalently to Klotho-sufficient thymus transplants, indicating that Klotho is not intrinsically essential for TEC support of thymopoiesis. Moreover, lethally irradiated hosts given Kl/Kl or wild-type bone marrow had normal thymocyte development and comparably reconstituted T cells, indicating that Klotho is not inherently essential for peripheral T cell reconstitution. Because Kl/Kl mice have higher levels of serum phosphorus, calcium, and vitamin D, we evaluated thymus function in Kl/Kl mice fed with a vitamin D–deprived diet. We observed that a vitamin D–deprived diet abrogated thymic involution and T cell lymphopenia in 8-wk-old Kl/Kl mice. Taken together, our data suggest that Klotho deficiency causes thymic involution via systemic effects that include high active vitamin D levels.
    Materialart: Online-Ressource
    ISSN: 0022-1767 , 1550-6606
    RVK:
    RVK:
    Sprache: Englisch
    Verlag: The American Association of Immunologists
    Publikationsdatum: 2018
    ZDB Id: 1475085-5
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 5
    In: Cancer Immunology Research, American Association for Cancer Research (AACR), Vol. 8, No. 9 ( 2020-09-01), p. 1139-1149
    Kurzfassung: Natural killer (NK) cells are potent immune modulators that can quickly lyse tumor cells and elicit inflammatory responses. These characteristics make them ideal candidates for immunotherapy. However, unlike T cells, NK cells do not possess clonotypic receptors capable of specific antigen recognition and cannot expand via activating receptor signals alone. To enable NK cells with these capabilities, we created and have previously described a tri-specific killer engager (TriKE) platform capable of inducing antigen specificity and cytokine-mediated NK-cell expansion. TriKE molecules have three arms: (i) a single-chain variable fragment (scFv) against the activating receptor CD16 on NK cells to trigger NK-cell activation, (ii) an scFv against a tumor-associated antigen (CD33 here) to induce specific tumor target recognition, and (iii) an IL15 moiety to trigger NK-cell expansion and priming. Here, we demonstrate that by modifying the anti-CD16 scFv with a humanized single-domain antibody against CD16, we improved TriKE functionality. A CD33-targeting second-generation TriKE induced stronger and more specific NK-cell proliferation without T-cell stimulation, enhanced in vitro NK-cell activation and killing of CD33-expressing targets, and improved tumor control in preclinical mouse models. Given these improved functional characteristics, we propose rapid translation of second-generation TriKEs into the clinic.
    Materialart: Online-Ressource
    ISSN: 2326-6066 , 2326-6074
    Sprache: Englisch
    Verlag: American Association for Cancer Research (AACR)
    Publikationsdatum: 2020
    ZDB Id: 2732517-9
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 6
    In: Experimental Hematology, Elsevier BV, Vol. 35, No. 4 ( 2007-04), p. 682-690
    Materialart: Online-Ressource
    ISSN: 0301-472X
    RVK:
    Sprache: Englisch
    Verlag: Elsevier BV
    Publikationsdatum: 2007
    ZDB Id: 2005403-8
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 7
    Online-Ressource
    Online-Ressource
    Ovid Technologies (Wolters Kluwer Health) ; 2008
    In:  Circulation Vol. 118, No. suppl_18 ( 2008-10-28)
    In: Circulation, Ovid Technologies (Wolters Kluwer Health), Vol. 118, No. suppl_18 ( 2008-10-28)
    Kurzfassung: Cellular therapy with non-hematopoietic adult stem cells (ASC) has emerged as a novel strategy for treatment of myocardial infarction (MI). Cells from non-identical donors, however, are typically rejected by the immune system of recipient. To overcome this barrier to transplantation we induced MI by left coronary artery ligation followed by direct intramyocardial injection of ASC or saline in cohorts of syngeneic C57BL/6 (B6) immune competent versus B6 Rag/IL2Rγc (Rag/γc) T-, B- and natural killer-cell immune deficient mice. We made an unexpected observation that heart function was significantly improved in ASC-treated B6 mice, but not in ASC-treated Rag/γc mice; and that the beneficial effect of ASC was inversely correlated with ASC persistence (i.e., ACS were rejected by B6 mice but engrafted in Rag/γc mice). As the donor cells were rejected within several weeks by B6 animals we hypothesized that the host immune system and ASC provided trophic signals for cardiac repair early after injury. In search for anatomical correlation, we first assessed changes in capillary density. Four weeks after MI, significantly more capillaries (normalized to number of nuclei) were observed in the border zone of B6 animals treated with ASC versus saline (p = 0.01), and significantly fewer capillaries were found in the infarct zone when B6 animals (treated with ASC) were depleted of T-cells and NK-cells (p = 0.03). To gain mechanistic insight into the early events in the ASC-mediated repair, next we have assessed one week after MI ± ASC messenger RNA expression of genes known to be engaged in angiogenesis. In B6 mice the most prominent change in response to MI injury was 17-fold increased expression of tissue inhibitor of metalloproteinases 1. The ASC mediated response to MI injury was defined by increased expression of fibroblast growth factor 2, integrin αV, phophorylated form of vascular endothelial growth factor receptor 2 and endothelial-specific receptor tyrosine kinase (all p 〈 0.01). These data are the first to define the paracrine tissue repair factors necessary to produce therapeutic benefit in response to donor ASC after MI. Importantly, our data also suggest that MI is not solely a heart lesion, but rather a systemic inflammatory condition controlled by host immune system. This research has received full or partial funding support from the American Heart Association, AHA National Center.
    Materialart: Online-Ressource
    ISSN: 0009-7322 , 1524-4539
    Sprache: Englisch
    Verlag: Ovid Technologies (Wolters Kluwer Health)
    Publikationsdatum: 2008
    ZDB Id: 1466401-X
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 8
    Online-Ressource
    Online-Ressource
    American Society of Hematology ; 2008
    In:  Blood Vol. 112, No. 11 ( 2008-11-16), p. 2413-2413
    In: Blood, American Society of Hematology, Vol. 112, No. 11 ( 2008-11-16), p. 2413-2413
    Kurzfassung: Our goal is to test mesenchymal stem cell therapy in a mouse model of Hutchinson-Gilford Progeria Syndrome (HGPS), a lethal childhood disorder for which no definitive therapy is available. HGPS patients have failure to thrive, lipodystrophy, skeletal dysplasia, sclerotic skin, alopecia, and occlusive vascular disease that results in premature death from myocardial infarction or stroke in early teens. In HGPS, the accumulation of incompletely processed nuclear architectural protein lamin A (a farnesylated version of prelamin A, termed progerin) results in dysfunction of multiple organ systems, particularly those of mesenchymal origin. Consistent with this, progerin has been shown to interfere with the proliferation and differentiation of mesenchymal stem cells (MSCs). Furthermore, MSC depletion is thought to account for the specific segmental nature of human progeria. The identification of HGPS-specific MSC dysfunction, and emerging evidence about the plasticity and paracrine effects of MSCs have prompted us to test the hypothesis that MSCs might be coaxed into becoming cells able to correct widespread pathology in HGPS. To determine whether MSCs can be used to rescue progeria phenotype, MSCs from wild-type donors were tested. First, donor MSCs (0.5 × 106 per recipient) were stably transfected to express the red fluoroform DsRed2, which permitted donor cell tracking in tissues post mortem. Next, to achieve wide biodistribution DsRed2+ MSCs were injected intra-arterially into 2-week-old ZMPSTE24−/− mutant mice. Like HGPS cells, ZMPSTE24−/− mutant mice accumulate progerin and the mice exhibit many progeria-like signs, including alopecia, micrognathia, dental abnormalities, osteolytic lesions in bones, osteoporosis, retarded growth, muscle weakness, and shortened lifespan. Therefore, survival, growth (measured by weight gain), and muscle weakness (measured by grip strength) were analyzed. MSC-treated (n = 13) versus untreated (n = 23) ZMPSTE24−/− mice had significantly increased survival (65% versus 100%), weight gain after 6 weeks of life, and grip strength (judged by the ability to hang onto an upside–down grid). These data are consistent with the hypothesis that the transfer of wild-type MSCs reduces the severity of the lamin A defect. To investigate whether the benefits associated with MSC infusion were attributable to persistent tissue engraftment or to a transient paracrine effect of donor MSCs, all mice were electively harvested at 20 weeks of age. Because dermal lipodystrophy, cardiac arteriosclerosis, and skeletal myopathy are prominent pathological findings in both human and murine progeria, post-mortem analyses focused on donor cell engraftment and progerin expression in corresponding organs of pathology (skin, liver, and skeletal muscle). Donor cells were identified in skin, liver, and skeletal muscle specimens with a frequency of 1%–5%, indicating that donor MSCs can repopulate tissue niches presumed to be dysfunctional in progeria. Experiments are ongoing to evaluate tissue levels of prelamin A and mature lamin A, abnormalities in nuclear shape, and pertubations in intracellular signaling pathway genes known to be dysregulated in human progeria. Collectively, these data demonstrate the proof of principle of MSC transfer for phenotypic reversion of lamin A defect in murine progeria. This may offer a valuable approach for treatment of human HGPS with human MSCs, which are already in clinical use.
    Materialart: Online-Ressource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Sprache: Englisch
    Verlag: American Society of Hematology
    Publikationsdatum: 2008
    ZDB Id: 1468538-3
    ZDB Id: 80069-7
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 9
    In: Blood, American Society of Hematology, Vol. 108, No. 11 ( 2006-11-16), p. 2554-2554
    Kurzfassung: The beneficial effects of Mesenchymal Stem Cells (MSC) are being tested clinically in attempts to improve hematopoietic engraftment, to treat osteogenesis imperfecta, graft-versus-host disease and autoimmune diseases, and to deliver therapy for malignancies. In early reports, phase I clinical studies have not been associated with toxicities. To study the biodistribution of MSC, we labeled adult murine C57BL/6 MSC with firefly luciferase and DsRed2 fluorescent protein using non-viral Sleeping Beauty transposons, and co-infused labeled MSC with bone marrow into irradiated allogeneic recipients. Using in vivo whole body imaging, luciferase signals were shown to be increased between weeks 3 and 12. Unexpectedly, some mice with the highest luciferase signals died and all surviving mice developed foci of sarcoma in lungs. Two mice also developed sarcomas in their extremities. Infusion of MSC-derived sarcoma cells resulted in malignant lesions in secondary recipients. Common cytogenetic abnormalities were identified in tumor cells isolated from different animals. Mapping of the Sleeping Beauty transposition insertion sites did not identify an obvious transposon-related genetic abnormality. Importantly, the original MSC cultures not labeled with transposons, as well as cultured MSC independently isolated from the bone marrow of both BALB/c and C57BL/6 mice showed cytogenetic aberrations after several passages in vitro. Even though not all MSC cultures formed tumors upon in vivo injection, these data indicate that MSC transformation was neither strain-specific nor a rare event following ex-vivo expansion. Karyotype analyses using fluorescence in situ hybridization with spectral karyotyping (SKY) as well as combined binary ratio labeling of nucleic acid probes (COBRA) showed clonal evolution of transformed MSC suggesting that the critical transformation event(s) occurred before MSC infusion. Collectively, we describe cytogenetic instability of murine MSC isolated in two independent laboratories, their cellular transformation, and potential for sarcoma formation. While the growth characteristics of human and murine MSC are not identical and murine cells are more prone to undergo immortalization and transformation in culture than human cells, our study highlights the importance of quality control measures needed for ongoing and future clinical trials using human MSC.
    Materialart: Online-Ressource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Sprache: Englisch
    Verlag: American Society of Hematology
    Publikationsdatum: 2006
    ZDB Id: 1468538-3
    ZDB Id: 80069-7
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 10
    In: Blood, American Society of Hematology, Vol. 106, No. 11 ( 2005-11-16), p. 4326-4326
    Kurzfassung: Mesenchymal stem cells (MSCs) can differentiate into non-hematopoietic cell types, including adipocytes, chondrocytes and osteocytes. MSCs have been isolated from multiple species, including humans, and multiple organs, including bone marrow, adipose tissue and umbilical cord blood. The beneficial effects of MSCs are being tested clinically in attempts to: improve hematopoietic engraftment, to treat osteogenesis imperfecta, graft-versus-host disease and autoimmune diseases, and as antitumor agents to deliver therapy for malignancies. Phase I clinical studies have not been associated with toxicities. We aimed to investigate the capacity of MSCs to aid in tissue healing after radiation induced injury in irradiated bone marrow transplant (BMT) recipients. To study the biodistribution of MSCs, we labeled adult murine C57BL/6 MSCs with firefly luciferase and DsRed2 fluorescent protein using non-viral Sleeping Beauty transposons, and co-infused them with allogeneic bone marrow into irradiated reipients. Using in vivo whole body bioluminenscent imaging luciferase signals were shown to be increased between weeks 3 and 12 indicating expansion of MSCs. Unexpectedly, some mice (N=8/17) with the highest luciferase signals died and all surviving mice (N=9/17) developed foci of ectopic ossification in lungs. Two of mice also developed osteosarcomas in their extremities. This prompted us to characterize the transformed MSCs that originated from the donor MSCs. The transformed cells were aneuploid, lost their capacity to differentiate into mesenchyme-derived adipocytes and chondrocytes, and histologically identified as osteosarcomas. In addition, infusion of tumor cells resulted in malignant lesions in secondary recipients. Mapping of transposition sites in the genome and karyotype analysis indicated that the critical transformation event(s) occurred before infusion of the MSCs. Even though we have not encountered a transformation event in & gt;100 mice infused with MSC manipulated with transposons, we speculated that mutation by transposition was the inciting event. None of the identifiable transposition events occurred in a known proto-oncogene or tumor suppressor gene. This does not discount the possibility of insertional mutagenesis as the genomic lesion may have occurred on the chromosome which was subsequently disrupted or lost. Alternatively, genomic instability could have been a result of spontaneous unrepaired chromosomal lesion(s) that preceded the transposon insertion and resulted in osteosarcoma. These findings provide evidence of evolution of MSCs with osteogenic capacity into osteosarcoma in vivo and are clinically relevant as they document the potential of ex vivo manipulated MSCs for transformation into malignant disease.
    Materialart: Online-Ressource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Sprache: Englisch
    Verlag: American Society of Hematology
    Publikationsdatum: 2005
    ZDB Id: 1468538-3
    ZDB Id: 80069-7
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...