A major problem limiting hematopoietic stem cell (HSC) gene therapy is the low efficiency of gene transfer into human HSCs using retroviral vectors. Strategies, which would allow in vivo expansion of ...gene-modified hematopoietic cells, could circumvent the problem. To this end, we developed a selective amplifier gene (SAG) consisting of a chimeric gene composed of the granulocyte colony-stimulating factor (G-CSF) receptor gene and the estrogen receptor gene hormone-binding domain. We have previously demonstrated that primary bone marrow progenitor cells transduced with the SAG could be expanded in response to estrogen in vitro. In the present study, we evaluated the efficacy of the SAG in the setting of a clinically applicable cynomolgus monkey transplantation protocol. Cynomolgus bone marrow CD34(+) cells were transduced with retroviral vectors encoding the SAG and reinfused into each myeloablated monkey. Three of the six monkeys that received SAG transduced HSCs showed an increase in the levels of circulating progeny containing the provirus in vivo following administration of estrogen or tamoxifen without any serious adverse effects. In one monkey examined in detail, transduced hematopoietic progenitor cells were increased by several-fold (from 5% to 30%). Retroviral integration site analysis revealed that this observed increase was polyclonal and no outgrowth of a dominant single clonal population was observed. These results demonstrate that the inclusion of our SAG in the retroviral construct allows selective in vivo expansion of genetically modified cells by a non-toxic hormone treatment.
Full text
Available for:
DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
A first principle band-calculation for the pseudo-binary compounds YCo4M and YNi4M with CaCu5-type hexagonal structure is carried out in the self-consistent linear muffin-tin orbital method within ...the atomic sphere approximation, where the M (=Ti, V, Cr, Mn, Fe, Co, Ni or Cu) atom occupies the 2c or 3g site. A preferential site occupation of the M atoms in YCo5 and YNi5 is discussed by comparing the calculated binding energies.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The development of highly efficient and safe gene transfer methods suitable for clinical use is required for human gene therapies. We have developed a novel lentiviral vector system, based on the ...nonpathogenic simian immunodeficiency virus from African green monkeys (SIVagm), that carries a unique dual gene expression system. This system utilizes the lentivirus Rev responsive element (RRE). Self-inactivating vectors were also developed by deleting a U3 region in the 3' long terminal repeat (3' LTR) of the virus. When pseudotyped with a vesicular stomatitis virus envelope glycoprotein G (VSV-G), the SIVagm-based vectors could transduce both growth-arrested human cells and terminally differentiated neuronal cell lines. Using these vectors, two reporter genes could be expressed simultaneously at equal levels, and expression levels of both genes could be altered by modifying the length of the RRE sequence. These SIVagm-based vectors might offer safety advantages over other lentivirus-based vectors. Furthermore, the novel dual gene expression system described here could increase the usefulness and value of both viral and nonviral vectors in gene therapy.
Preparation of epitaxial YBa(2)Cu(3)O(7) (YBCO) films on cerium oxide-buffered sapphire (r-cut a-Al(2)O(3)) substrates by an excimer-laser-assisted metalorganic deposition (ELAMOD) is reported. The ...ELAMOD process has been developed to bring about the advantage of shorter heating time than that in the conventional metalorganic deposition; the coated films are irradiated by an excimer laser beam before firing. We initiated the ELAMOD-YBCO process using a homogenized 8-mm-square laser beam which irradiates the coated surface in a fixed substrate mode. In order to extend the process applicable to large-area films, a scan irradiation mode was employed and a high critical-current density over 6 MA/cm(2) has been observed. In the process, an appropriate choice of laser energy is difficult but crucial to obtain YBCO films with high superconducting properties. Then, laser irradiation from backside of the substrate was examined and proved to be beneficial to extend the experimental window of the laser energy. Moreover, a newly developed ELAMOD process using a 90-mm-wide line-beam is also reported which has a potential ability for large-area applications.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
39.
A Seed for Alzheimer Amyloid in the Brain Hayashi, Hideki; Kimura, Nobuyuki; Yamaguchi, Haruyasu ...
The Journal of neuroscience,
05/2004, Volume:
24, Issue:
20
Journal Article
Peer reviewed
Open access
A fundamental question about the early pathogenesis of Alzheimer's disease (AD) concerns how toxic aggregates of amyloid beta protein (Abeta) are formed from its nontoxic soluble form. We ...hypothesized previously that GM1 ganglioside-bound Abeta (GAbeta) is involved in the process. We now examined this possibility using a novel monoclonal antibody raised against GAbeta purified from an AD brain. Here, we report that GAbeta has a conformation distinct from that of soluble Abeta and initiates Abeta aggregation by acting as a seed. Furthermore, GAbeta generation in the brain was validated by both immunohistochemical and immunoprecipitation studies. These results imply a mechanism underlying the onset of AD and suggest that an endogenous seed can be a target of therapeutic strategy.