Expansion and transduction of nonenriched human cord blood cells using HS-5 conditioned medium and FLT3-L

3D-nanoflowers of rutile TiO2 as a film grown on conducting and non-conducting glass substrates for in vitro biocompatibility studies with mouse MC3T3 osteoblast and human HS-5 cells

Thin films of 3D-nanoflowers of rutile TiO₂ on conducting (FTO and ITO) and non-conducting (glass) substrates were grown using a surfactant free one-step hydrothermal process.

A preclinical model of double- versus single-unit unrelated cord blood transplantation

Cord blood transplantation (CBT) with units containing total nucleated cell (TNC) dose >2.5 x 10(7)/kg is associated with improved engraftment and decreased transplant-related mortality. For many adults no single cord blood units are available that meet the cell dose requirements. We developed a dog model of CBT to evaluate approaches to overcome the problem of low cell dose cord blood units. This study primarily compared double- versus single-unit CBT. Unrelated dogs were bred and cord blood units were harvested. We identified unrelated recipients that were dog leukocyte antigen (DLA)-88 (class I) and DLA-DRB1 (class II) allele-matched with cryopreserved units. Each unit contained Collapse

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MESH Headings

• Animals
• Cord Blood Stem Cell Transplantation/adverse effects
• Cord Blood Stem Cell Transplantation/methods
• Disease Models, Animal
• Dogs
• Female
• Graft Rejection/immunology
• Male
• Survival Rate

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Grants

• U19 AI067770-02 NIAID NIH HHS
• U19 AI067770-030005 NIAID NIH HHS
• U19 AI067770-05 NIAID NIH HHS
• U19 AI 067770 NIAID NIH HHS
• U19 AI067770-01 NIAID NIH HHS
• R01 DK042716 NIDDK NIH HHS
• DK42716 NIDDK NIH HHS
• R01 DK042716-15 NIDDK NIH HHS
• P30 CA015704 NCI NIH HHS
• CA78902 NCI NIH HHS
• U19 AI067770 NIAID NIH HHS
• U19 AI067770-050005 NIAID NIH HHS
• P30 CA015704-35 NCI NIH HHS
• CA15704 NCI NIH HHS
• U19 AI067770-010005 NIAID NIH HHS
• R01 DK042716-16 NIDDK NIH HHS
• P30 CA015704-34 NCI NIH HHS
• U19 AI067770-04 NIAID NIH HHS
• P01 CA078902 NCI NIH HHS
• P01 CA078902-11 NCI NIH HHS
• P01 CA078902-10 NCI NIH HHS
• U19 AI067770-040005 NIAID NIH HHS
• U19 AI067770-020005 NIAID NIH HHS

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Affiliation(s)

George E Georges Clinical Research Division, Fred Hutchinson Cancer Research Center, University of Washington, Seattle, Washington 98109, USA.
Vladimir Lesnikov
Szczepan W Baran
Anna Aragon
Marina Lesnikova
Robert Jordan
Ya-Ju Laura Yang
Murad Y Yunusov
Eustacia Zellmer
Shelly Heimfeld
Gopalakrishnan M Venkataraman
Michael A Harkey
Scott S Graves
Rainer Storb
Barry E Storer
Richard A Nash

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Identification of DJ-1/PARK-7 as a determinant of stroma-dependent and TNF-alpha-induced apoptosis in MDS using mass spectrometry and phosphopeptide analysis

In patients with myelodysplastic syndromes (MDS), apoptosis in hematopoietic cells is up-regulated in low-grade disease, whereas advanced disease is characterized by apoptosis resistance. We have shown that marrow stroma-derived signals convey sensitivity to tumor-necrosis-factor alpha (TNF-alpha)-mediated apoptosis in otherwise-resistant KG1a myeloid cells and CD34(+) cells from MDS marrow. Here, we used a PhosphoScan proteomic liquid chromatography-mass spectrometry method to identify signals relevant for this effect. The transcription factor DJ-1/PARK-7 (DJ-1) was highly phosphorylated in KG1a cells cultured without stroma but dephosphorylated after stroma coculture, whereas expression of p53 increased significantly, suggesting a stroma contact-dependent effect of DJ-1 on p53. In CD34(+) marrow cells from advanced MDS, expression of DJ-1 was up-regulated, whereas p53 levels were low, resulting in significantly greater DJ-1/p53 ratios than in patients with low-grade MDS (P = .01). DJ-1 levels were correlated with increasing International Prognostic Scoring System scores (P = .006). Increasing DJ-1/p53 ratios were associated with an increased risk of mortality, although the correlation did not reach statistical significance (P = .18). These data suggest that DJ-1/p53 interactions contribute to apoptosis resistance in clonal myeloid cells and may serve as a prognostic marker in patients with MDS.

No telomere shortening in marrow stroma from patients with MDS

Telomere shortening with age may lead to genomic instability and an increased risk of cancer. Given the role of the microenvironment in the pathophysiology of the myelodysplastic syndrome (MDS), primarily a disease of older age, we determined telomere length in primary cultured marrow stroma cells using quantitative fluorescent in situ hybridization (qFISH) and quantitative polymerase chain reaction (qPCR). qFISH showed comparable rates of decrease in telomere length with age in MDS patients and age-matched healthy controls. Telomere length assessment by qPCR showed similar results. These findings suggest a lack of significant differences between MDS patients and healthy controls in terms of telomere stability in marrow stroma in contrast to that observed in hematopoietic cells. In conclusion, this demonstrates that, although MDS stroma cells and hematopoietic cells share the same microenvironment, the stromal cells do not share the processes that contribute to accelerated telomere attrition, suggesting that stromal cell proliferative potential is not limiting in MDS.

Differentiation of human embryonic stem cells into immunostimulatory dendritic cells under feeder-free culture conditions

PURPOSE

The objective of this study was to develop a scalable and broadly applicable active immunotherapy approach against cancer, circumventing the limitations typically encountered with autologous vaccination strategies. We hypothesized that human embryonic stem cells (hESC) can serve as a virtually unlimited source for generating dendritic cells (DC) with potent antigen-presenting function. Here, we investigated the developmental processes and requirements for generating large numbers of mature, antigen-presenting DC from pluripotent hESC.

EXPERIMENTAL DESIGN

A feeder cell-free culture system was developed to differentiate hESC into mature DC sequentially through hematopoietic and myeloid precursor stages.

RESULTS

Using this method, we were able to yield large numbers of mature immunostimulatory DC from hESC to enable clinical investigation. Upon activation, the hESC-derived DC secreted interleukin-12p70, migrated in response to MIP-3beta, and exhibited allostimulatory capacity. Most importantly, antigen-loaded, hESC-derived DC were capable of stimulating potent antigen-specific CD8(+) T-cell responses in an HLA class I-matched semiallogeneic assay system. Moreover, HLA class II-mismatched hESC-derived DC induced a potent Th1-type cytokine response without expanding FOXP3(+) regulatory T cells in vitro.

CONCLUSIONS

These data suggest the development of a novel active immunotherapy platform to stimulate potent T-cell immunity in patients with intractable diseases, such as cancer or viral infection.

The farnesyltransferase inhibitor L744832 potentiates UCN-01-induced apoptosis in human multiple myeloma cells

PURPOSE

The purpose of this study was to characterize interactions between the farnesyltransferase inhibitor L744832 and the checkpoint abrogator UCN-01 in drug-sensitive and drug-resistant human myeloma cell lines and primary CD138+ multiple myeloma cells.

EXPERIMENTAL DESIGN

Wild-type and drug-resistant myeloma cell lines were exposed to UCN-01 +/- L744832 for 24 hours, after which mitochondrial injury, caspase activation, apoptosis, and various perturbations in signaling and survival pathways were monitored.

RESULTS

Simultaneous exposure of myeloma cells to marginally toxic concentrations of L744832 and UCN-01 resulted in a synergistic induction of mitochondrial damage, caspase activation, and apoptosis, associated with activation of p34cdc2 and c-Jun-NH2-kinase and inactivation of extracellular signal-regulated kinase, Akt, GSK-3, p70(S6K), and signal transducers and activators of transcription 3 (STAT3). Enhanced lethality for the combination was also observed in primary CD138+ myeloma cells, but not in their CD138- counterparts. L744832/UCN-01-mediated lethality was not attenuated by conventional resistance mechanisms to cytotoxic drugs (e.g., melphalan or dexamethasone), addition of exogenous interleukin-6 or insulin-like growth factor-I, or the presence of stromal cells. In contrast, enforced activation of STAT3 significantly protected myeloma cells from L744832/UCN-01-induced apoptosis.

CONCLUSIONS

Coadministration of the farnesyltransferase inhibitor L744832 promotes UCN-01-induced apoptosis in human multiple myeloma cells through a process that may involve perturbations in various survival signaling pathways, including extracellular signal-regulated kinase, Akt, and STAT3, and through a process capable of circumventing conventional modes of myeloma cell resistance, including growth factor- and stromal cell-related mechanisms. They also raise the possibility that combined treatment with farnesyltransferase inhibitors and UCN-01 could represent a novel therapeutic strategy in multiple myeloma.

Human cytomegalovirus plasmid-based amplicon vector system for gene therapy

We have constructed and evaluated the utility of a helper-dependent virus vector system that is derived from Human Cytomegalovirus (HCMV). This vector is based on the herpes simplex virus (HSV) amplicon system and contains the HCMV orthologs of the two cis-acting functions required for replication and packaging of HSV genomes, the complex HCMV viral DNA replication origin (oriLyt), and the cleavage packaging signal (the a sequence). The HCMV amplicon vector replicated independently and was packaged into infectious virions in the presence of helper virus. This vector is capable of delivering and expressing foreign genes in infected cells including progenitor cells such as human CD34+ cells. Packaged defective viral genomes were passaged serially in fibroblasts and could be detected at passage 3; however, the copy number appeared to diminish upon serial passage. The HCMV amplicon offers an alternative vector strategy useful for gene(s) delivery to cells of the hematopoietic lineage.

A novel human packaging cell line with hematopoietic supportive capacity increases gene transfer into early hematopoietic progenitors

The hematopoietic stem/progenitor cell (HSPC) represents the ideal target for gene therapy of disorders of the hematopoietic system, but still faces problems related to ex vivo manipulation and gene transfer efficiency. We demonstrate that soluble factors from the human endothelial-like cell line ECV 304/T24 support the growth of human CD34(+) progenitor cells as primary human bone marrow stroma and increase the rate of gene transfer into progenitor cells up to 5-fold. ECV 304/T24 was used to generate split-function amphotropic packaging cell lines (named APEX) with the purpose of combining, in the same cells, hematopoietic support and gene transfer vehicle functions. The APEX cell lines were negative for the presence of replication-competent retroviruses and produced complement-resistant vector particles. When mobilized peripheral blood or umbilical cord blood CD34(+) cells were exposed once to APEX supernatants, the level of gene transfer was equivalent to that observed with GP + Am12, in spite of the lower titer of the APEX producers. More importantly, APEX supernatants gave rise reproducibly to a 2-fold increase in transduction of early progenitors (long-term culture-initiating cells), reaching on average 50% gene transfer. This novel packaging cell represents a significant advance in HSPC genetic modification technology, combining both a beneficial hematopoietic supportive effect and the gene transfer vector function in a human-based system.