Chemistry: molecular biology and microbiology – Micro-organism – tissue cell culture or enzyme using process... – Recombinant dna technique included in method of making a...
Reexamination Certificate
1998-04-27
2003-04-01
Kemmerer, Elizabeth (Department: 1646)
Chemistry: molecular biology and microbiology
Micro-organism, tissue cell culture or enzyme using process...
Recombinant dna technique included in method of making a...
C435S069400, C435S069500, C435S320100, C435S325000, C435S252300, C435S254110, C530S350000, C530S351000, C530S399000, C530S387100, C530S387900, 57, 57
Reexamination Certificate
active
06541217
ABSTRACT:
This application is a 371 of PCT/JP97/02985, filed Aug. 27, 1997.
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a novel hematopoietic growth factor protein termed hematopoietic stem cell growth factor (hereinafter referred to as “SCGF”) which acts on hematopoietic stem cells to maintain their survival and to induce their proliferation and differentiation. The present invention also relates to a gene coding for SCGF; a vector comprising the gene; a transformant transformed with the vector; a method for producing SCGF; and a method for separating and purifying SCGF. The present invention further relates to the use of SCGF as a therapeutic for hematopoietic insufficiency derived from irradiation or chemotherapy for patients with various hematopoietic diseases or cancers; or the use of SCGF as a reagent for diagnostic analysis. The present invention also relates to the use of SCGF in bone marrow transplantation for the purpose of hematopoietic recovery, for which hematopoietic stem cells can be amplified with SCGF in vitro in a small amount of bone marrow aspirates; and the use of SCGF in gene therapy to improve the efficiency of a gene transfer into hematopoietic stem cells. The invention also relates to a vector developed to isolate the SCGF gene, as well as a method for isolating the gene. The vector and the method can provide promising tools to search for other novel genes for unknown proteins.
TECHNICAL BACKGROUND OF THE INVENTION
Hematopoiesis in the bone marrow is regulated by direct interaction between (i) self-renewable hematopoietic stem cells, hematopoietic progenitor cells derived therefrom and committed to respective differentiation pathways and cell populations at consecutive differentiation stages between the above two types of cells, and (ii) stromal cells as hematopoietic inductive microenvironment supporting the above cells, or by indirect interaction between (i) cells and hematopoietic humoral factors secreted by (ii) cells. A number of hematopoietic humoral factors are also secreted by extramedullary organs such as the kidney or the liver. Peripheral blood cells with a limited life span are continuously recruited through the hematopoietic network spreading over the whole body which results in maintaining the hamarological stasis. The complicated hematopoietic mechanisms have been analyzed using the following two approaches; first, the process of hematopoietic recovery from myelosuppression is studied in vivo in the experimental animals such as mouse, dog or sheep, which are irradiated or given cytotoxic reagents such as 5-fluorouracil. Second, interaction between hematopoietic stem cells and stromal cells or humoral factors is studied in vitro, using a clonal culture of the human and mammalian bone marrow cells.
With the progress in molecular biology, a number of genes for cytokines including hematopoietic growth factors have been successfully cloned. Such cytokines include erythropoietin (hereinafter referred to as “Epo”), thrombopoietin, colony stimulating factors such as granulocyte colony-stimulating factor (hereinafter referred to as “G-CSF”), macrophage colony-stimulating factor (hereinafter referred to as “M-CSF”), granulocyte macrophage colony-stimulating factor (hereinafter referred to as “GM-CSF”) interleukins such as IL-1, IL-3, IL-4, IL-5, IL-6, IL-9, IL-11 and IL-12 recently identified stem cell factor (SCF) and flk-2/flt3 ligand (Lin et al., Proc. Natl. Acad. Sci. USA 82, 7580-7584, 1985; de Sauvage et al., Nature 369, 533-538, 1994; Nagata et al., EMBO J. 5, 575-581, 1986; Wong et al., Science 235, 1504-1508, 1987; Miyatake et al., EMBO J. 4, 2561-2568, 1985; Clark et al., Nucleic Acids Res. 14, 7897-7914, 1986; Dorssers et al., Gene 55, 115-124, 1987; Yokota et al., Proc. Natl. Acad. Sci. USA 83, 5894-5898, 1986; Campbell et al., Proc. Natl. Acad. Sci. USA 84, 6629-6633, 1987; Yasukawa et al., EMBO J. 6, 2939-2945, 1987; Yang et al., Blood 74, 1880-1884, 1989; Paul et al., Proc. Natl. Acad. Sci. USA 87, 7512-7516, 1990; Wolf et al., J. Immunol, 146, 3074-3081, 1991; Anderson et al., Cell 63, 235-243, 1990; Lyman et al., Cell 75, 1157-1167, 1993). These cytokines have been well characterized biologically and biochemically, and their industrial production has become possible. G-CSF, M-CSF and Epo are used clinically as recombinant preparations for hematopoietic insufficiency derived from irradiation or chemotherapy and anemia associated with renal failure, respectively. However, when hematopoietic insufficiency due to quantitative or qualitative hematopoietic stem cell abnormalities is treated with the recombinant hematopoietic growth factors, peripheral blood counts are only transiently improved. Hematopoietic insufficiency often recurs with cessation of the hematopoietic growth factors. In other words, presently available hematopoietic growth factors have not achieved radical cure of hematopoietic insufficiency due to hematopoietic stem cell abnormalities.
Auto- or allo-graft of bone marrow, peripheral blood and cord blood hematopoietic stem cells are common procedures for hematopoietic insufficiency. On the other hand, hematopoietic stem cells in the bone marrow, peripheral blood or cord blood cells are tried to be the amplified in vitro with hematopoietic growth factors and then transplanted. Among the factors described above, SCF, IL-3, G-CSF and IL-6 play a major role in amplification of hematopoietic stem cells and immature progenitors. These factors are known to exhibit the so-called “synergistic effect”, i.e. they induce higher amplification when used in combination than when used alone. Mouse hematopoietic stem cells can be amplified in vitro to 10-fold and progenitor cells to 1000-fold in response to the hematopoietic growth factors. In human, however, an expected amplification effect has not been achieved with the combination of SCF, IL-3, G-CSF and IL-6 that is effective in the mouse system (Bernstein et al., Blood 77, 2316-2321, 1991; Brandt et al., Blood 79, 634-641, 1992; Srour et al., Blood 81, 661-669, 1993). This not only implies that human cells expressing the receptors for the hematopoietic growth factors are different from mouse ones, but strongly suggests the existence of unknown factors involved in human hematopoiesis.
When host cells are transfected or infected, in gene therapy, with a retrovirus vector carrying a normal gene or a gene of interest, the efficiency of gene transfer will be extremely low if the host cells are not in the cell cycle and, as a result, no expression of the gene can be achieved. If a gene is transferred into the short-lived mature blood cells, gene therapy should be repeated many times since the expression of the gene is transient. Therefore, hematopoietic stem cells are a preferable target for gene transfer, for the reason that it is therapeutically excellent to transfer a gene of interest into hematopoietic stem cells once to thereby supply cells expressing the gene permanently. However, since hematopoietic stem cells are usually quiescent in the G
0
phase, attempts have been made to enter them into the cell cycle using a combination of hematopoietic growth factors such as SCF, IL-3, G-CSF, IL-6 and so forth. The efficiency of gene-transfer is still as low as 40%, which is the biggest problem in gene therapy (Nolta et al., Hum. Gene Therapy 1, 257-268, 1990; Stoeckert et al., Exp. Hematol. 18, 1164-1170, 1990; Dick et al., Blood 78, 624-634, 1991; Cournoyer et al., Hum. Gene Therapy 2, 203-213, 1991; Hughes et al., J. Clin. Invest. 89, 1817-1824, 1992).
Hiraoka et al. have found a growth activity on human hematopoietic stem cells in the culture supernatant of normal human peripheral blood mononuclear cells and that of undifferentiated myeloid KPB-M15 cells established from the peripheral blood leukocytes of the patient with chronic myelogenouse leukemia in blast crisis, designated the activity “hematopoietic stem cell growth factor” (SCGF) and tried to purify the factor (Hiraoka et al., Cell Biol. Int. Rep.10, 347-355, 1986; Hiraoka et al., Cancer Res. 47, 5025-5030, 1987).
Hiraoka Atsunobu
Mio Hiroyuki
Sugimura Atsushi
Kemmerer Elizabeth
Kyowa Hakko Kogyo Co. Ltd.
LandOfFree
Hematopoietic stem cell growth factor (SCGF) does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Hematopoietic stem cell growth factor (SCGF), we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Hematopoietic stem cell growth factor (SCGF) will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3093064