| Co-Investigator(Kenkyū-buntansha) |
IMAGAWA Shigehiko Jichi Medi. School, Dept. Medi., Assistant, 医学部, 助手 (60231164)
MIWA Akiyoshi Jichi Medi. School, Dept. Medi., Assistant Prof., 医学部, 講師 (40200224)
MUROI Kazuo Jichi Medi. School, Dept. Medi., Assistant, 医学部, 助手 (50190939)
KOMATSU Norio Jichi Medi. School, Dept, Medi., Assistant, 医学部, 助手 (50186798)
SUDA Toshio Jichi Medi. School, Dept. Medi., Associate Prof., 医学部, 助教授 (60118453)
|
|---|
| Research Abstract |
The purpose of this research is to sort out and concentrate hemopoietic stem cells, which is only a minor population of hemopoietic tissue, to study their reactivity to growth factors, and finally to investigate the clinical applications.
The main results are as follows :
1) We sorted CD34^+CD33^- cell fraction from normal human bone marrow cells by a fluorescence activated cell sortor (FACS), which contain the most primitive stem cells. After treating these cells with IL-3, they turned into CD34^- CD33^+ cells and then were induced to mature blood cells by the addition of lineage specific cytokines such as IL-5 and G-CSF.
2) Murine hemopoietic cells were sorted by various monoclonal antibodies using a FACS. The c-kit^+, SCA-1^+ lineage^- cells were found to contain highly enriched primitive stem cells. They could reconstitute murine hemopoiesis when injected into lethally irradiated mice.
3) Sorted stem cells were of middle-size with round, immature nuclei and basophilic cytoplasm occasionally with some granules.
4) We established a riiegakaryocytic cell line, UT-7, which is completely dependent on various cytokines such as IL-3, GM-CSF, erythropoietin or IL-6. We investigated the appearance of erythropoietin receptors and followed the signal transduction pathways. A mucopolysaccharide was extracted and purified from this cell line cells, which induced the "differentiation" of original UT-7 cells when added in vitro.
5) Several anti-sugar chain monoclonal antibody were became available. Some of them were shown to recognize human leukemic cells, but not the normal sorted stem cells. This phenomenon could be applied on the purging of leukemic cells from patient bone marrow at the time of autologous bone marrow transplantation.
As a conclusion, our research projects yielded many valuable results published in leading international journals, and could be useful for both basic and clinical study on the hemopoiesis.
|
