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Biomedical subjects

Y Kitamura

Publications and source records attributed to Y Kitamura.

At least 811 records · Page 45Linked to original sources
PubMed1979

Clonal nature of mast-cell clusters formed in W/Wv mice after bone marrow transplantation.

We have recently found that the number of mast cells in the skin of adult W/Wv mice is less than 1% of that observed in congeneic +/+ mice, and that no mast cells are detected in other tissues of W/Wv mice. After the transplantation of bone marrow cells from congeneic +/+ mice, the number of mast cells in the skin, stomach, caecum and mesentery of the W/Wv mice increased to levels similar to those of the +/+ mice. Study of the mast-cell number in the W/Wv mice at various times after transplantation suggested to use that mast cells might develop in groups, particularly in the skin and mesentery. In this report, we have attempted to elucidate the possible clonal origin of such mast-cell clusters from a single precursor cell, using giant granules of beige (C57BL/6-bgJ/bgJ, Chediak-Higashi syndrome) mice as a marker to identify the origin of the mast cells (Fig. 1). We found that when WB-W/+xC57BL/6-Wv (WBB6F1)-W/Wv mice were injected with a mixture of bone marrow cells from beige C57BL/6 mice and normal C57BL/6 mice, more than 95% of mast-cell clusters consisted of either beige-type cells alone or normal-type cells alone. We conclude, therefore, that the cluster of mast cells originated from a single precursor cell.

Animals↗
PubMed1979

Presence of mast cell precursors in peripheral blood of mice demonstrated by parabiosis.

The presence of mast cell precursors in peripheral blood was examined. The beige C57BL/6 (bgj/bgj, Chediak-Higashi syndrome) mouse was parabiosed with the normal C57BL/6 mouse. Mast cells containing giant granules and originating in the beige partner appeared in the normal parabiont. A comparable proportion of normal-mouse-type mast cells developed in the beige parabiont as well. In spite of the low radiosensitivity of mature mast cells, irradiation of the normal parabiont reduced the proportion of normal-mouse-type mast cells appearing in the beige partner. It was concluded, therefore, that the precursors of mast cells can migrate through the bloodstream.

Animals↗
PubMed1979

Development of androgen-independent spindle cell tumors from androgen-dependent medullary Shionogi carcinoma 115 in androgen-depleted nude mice.

When Shionogi carcinoma 115 (SC115, undifferentiated medullary carcinoma showing compact cell pattern and containing androgen receptor) was transplanted into male and female DS mice, it grew only in males. In contrast to this strict androgen dependency in DS hosts, tumors composed of spindle-shaped cells appeared in more than 80% of cases when SC115 tumor was inoculated into female or castrated male nude athymic (BALB/c-nu/nu) recipients. These spindle cell tumors neither contained cytosol androgen receptor nor showed biologically defined androgen dependency. As spindle cell tumors could be serially transplanted in DS mice but not in BALB/c-+/+ mice and as the original SC115 (medullary carcinoma showing a compact cell pattern) tumor and the spindle cell tumor had many identical chromosome abnormalities, these two types of tumors seem to have a common origin in spite of their morphological, biochemical, and biological differences. Since spindle cells could not be detected histologically in SC115 tumors maintained in intact male DS mice, the present results seem to suggest that SC115 cells may change their morphological, biochemical, and biological characteristics within one passage in androgen-depleted nude athymic mice.

Androgens↗
PubMed1979

Local development of mast cells from bone marrow-derived precursors in the skin of mice.

A mechanism to control development of mast cells was investigated in mice. Although mast cells in the skin of normal C57BL/6 mice were still of host type 290 days after irradiation and injection of bone marrow cells from beige (Chediak-Higashi syndrome, C57BL/6 bgJ/bgJ) mice, donor-type mast cells with giant granules appeared after painting of methylcholanthrene on the dorsal skin. Since donor-type mast cells appeared only at the painted portion of the skin, with an increase in the labeling index of such donor-type mast cells with 3H-thymidine, proliferation and differentiation of bone marrow-derived precursors of mast cells seem to be controlled locally. Although the morphologic feature of marrow-derived precursors was not identified, the finding that all fibroblasts cultured from the methylcholanthrene-treated skin were of host type may exclude the possibility that fibroblasts are the precursors of mast cells.

Bone Marrow Cells↗
PubMed1978

Development of haematopoietic colonies on the macrophage layer formed in the peritoneal cavity of S1/S1d mice.

The colony-forming ability of haematopoietic cells was examined on the macrophage layer formed in the peritoneal cavity of S1/S1d mice. The bone marrow cells of the congenic +/+ mice formed many macroscopic colonies on the macrophage layer of the S1/S1d mice although they did not form macroscopic colonies in the spleens of the same S1/S1d recipients. The size and the differentiation pattern of colonies on the macrophage layer of the S1/S1d mice were comparable to those of the colonies on the macrophage layer of the +/+ mice. There are two possible explanations for these results: (a) The microenvironmental defect of the S1/S1d mice has a more prominent effect on the development of spleen colonies than that of macrophage-layer colonies because 'Steel' locus may not be expressed significantly in the peritoneal macrophages or (b) because the cells that make colonies on the macrophage layer may be more differentiated cells than the multipotential stem cells that make colonies in the spleen.

Animals↗