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Biomedical subjects

K Harigaya

Publications and source records attributed to K Harigaya.

At least 55 records · Page 3Linked to original sources
PubMed1993

Establishment of a cell line from a human giant cell tumor of bone.

A cell line (CG-1) was established from a specimen of a 21-year-old woman with giant cell tumor of bone. Inverted-phase microscopic analysis showed that the cultured cells were spindle-shaped in appearance. Multinucleated giant cells and macrophagelike round cells characterizing the histology of giant cell tumor of bone were not found. It is believed that the spindle-shaped cells were the neoplastic element of this tumor, because they were cultured more than 40 passages over the course of one year and subsequent cytogenetic analysis with a G-band technique showed constant loss of chromosomes 14 and 19. The cell line was found to produce several cytokines: M-CSF, IFN-gamma and TNF-alpha, as demonstrated by Western blotting analysis. These cytokines are known to show chemotactic, differentiation-inducing, and activating effects on macrophages. Because it has been recently reported in the literature that there are many infiltrated macrophages in giant cell tumor of bone, and because multinucleated giant cells are formed by fusion of macrophages, the newly established cell line may prove a useful system in studying the nature of giant cell tumor of bone.

Adult↗
PubMed1992

Tumor necrosis factor and interleukin-1 induce activin A gene expression in a human bone marrow stromal cell line.

Activin A, a homodimer of the beta A chain, regulates hematopoiesis. In a human bone marrow-derived stromal cell line, KM-102, phorbol myristate acetate, tumor necrosis factor-alpha and interleukin-1 beta induced great increases in beta A chain mRNA levels and production of activin A activities. The phorbol ester-induced beta A chain gene expression was inhibited by cycloheximide and down regulation of protein kinase C, whereas the cytokine-induced expression was little affected by these treatments. These results indicate that the inflammatory cytokines directly stimulate beta A chain gene expression via protein kinase C-independent pathways.

Activins↗
PubMed1991

Monoclonal antibody against bone marrow stromal cells. Its production and characterization.

Bone marrow stromal cells play an essential role in the proliferation and differentiation of hematopoietic stem cells (1, 2). As a means of analyzing of the bone marrow microenvironment immunohistochemically, we attempted to produce a rat monoclonal antibody against the murine preadipocyte line H-1 derived from long-term bone marrow culture (LTBMC) of C57BL/6 mice (3, 4). A newly established monoclonal antibody, designated R4-A9, was obtained from a hybridoma prepared by fusion of Y.B2/3.0Ag20(YO) rat myeloma cells with spleen cells of LEW rats immunized with H-1 cells. The immunofluorescence of live H-1 cells showed that the antigen reacting with this antibody was strongly expressed on the cell surface. The specificity of R4-A9 was assessed immunohistochemically on frozen sections of various tissues from normal adult mice. R4-A9 demonstrated specificity for hematopoietic stroma in bone marrow and spleen. No staining was observed in thymus, lymph nodes or other tissues examined, with the exception of Leydig cells in the testis and the endothelium of small arteries in several organs. Detailed immunohistochemical observations at both the light microscopy and electron microscopy level showed that R4-A9 selectively reacted with the sinusoidal endothelium, perisinusoidal adventitial cells (5) (adventitial reticular cells (6] and intersinusoidal reticular cells (5) and the reticular cells of the splenic red pulp. These findings indicate that reticular cells and the endothelium of the bone marrow possess the common cell surface molecules recognized by R4-A9. SDS-PAGE analysis showed that R4-A9-immunoprecipitated proteins had a molecular mass of 100 kDa under reducing conditions.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Colony-stimulating factor 1 expression is down-regulated during the adipocyte differentiation of H-1/A marrow stromal cells and induced by cachectin/tumor necrosis factor.

We isolated clonal sublines of the established mouse marrow stromal cell line, H-1. These clonal sublines underwent differentiation into adipocytes in various degrees. One subline, H-1/A, underwent adipocyte differentiation after confluence, while another subline, H-1/D, did not differentiate. In H-1/A cells, the 4.5- and 2.5-kb major mRNA species of colony-stimulating factor 1 (CSF-1) were expressed before differentiation and were down-regulated at a posttranscriptional level during the differentiation of H-1/A cells. The down-regulation of the CSF-1 gene was not a result of arrested cellular growth, because no down-regulation was detected in the nondifferentiating sister line, H-1/D. This down-regulation appeared to be an early event in differentiation. Cachectin/tumor necrosis factor transiently induced the expression of CSF-1 and inhibited the differentiation of H-1/A cells into adipocytes. This induced expression of CSF-1 was due to an increased rate of transcription.

Adipose Tissue↗
PubMed1991

Expression of functional molecules in non-Hodgkin's lymphoma. Correlation with bone marrow involvement and serum LDH value.

It is well known that non-Hodgkin's lymphoma (NHL) cells express various antigens which are normally involved in a variety of functions. In addition, NHL is diverse in its proliferative capacity. To investigate the relation between these factors and the clinical picture, 45 cases of NHL were studied by immunohistochemistry using snap-frozen materials obtained before therapy. Reactivities with 27 monoclonal antibodies were examined and the results were correlated with clinical findings. The expression of surface mu and ICAM-1 in B-NHLs and CD25 in T-NHLs were significantly associated with bone marrow involvement. B-NHLs without expression of CD21(B2) and T-NHLs with CD25 were seen more frequently in cases with a LDH value of over 500 units/ml. The positivity rate of Ki-67 on B-NHLs was correlated with serum LDH value, NHL histologic classification, and overall survival. These data indicate that immunophenotyping and determination of the proliferative capacity of NHL are of value not only for confirmation of the histopathologic classification of the tumor but also for assessment of clinical behavior.

Adult↗
PubMed1990

Tissue inhibitor of metalloproteinases from human bone marrow stromal cell line KM 102 has erythroid-potentiating activity, suggesting its possibly bifunctional role in the hematopoietic microenvironment.

In this study, we demonstrated that tissue inhibitor of metalloproteinases (TIMP) produced by human bone marrow stromal cell line KM-102 had erythroid-potentiating activity (EPA) which stimulates the proliferation of erythroid progenitor cells. We, then, propose a scheme for the bifunctional role of TIMP/EPA in hematopoietic microenvironment, that is, the maintenance of the integrity of bone marrow matrix and the proliferation of erythroid progenitor cells proceeding on the matrix.

Bone Marrow↗
PubMed1990

Gamma-irradiation response of cocultivated bone marrow stromal cell lines of differing intrinsic radiosensitivity.

There is evidence for differences in the gamma-irradiation response of different cellular lineages within the bone marrow microenvironment. We previously reported that heterogeneity is demonstrable in the gamma-irradiation response of five clonal stromal cell lines, derived from one human bone marrow specimen, despite morphological, histochemical, cytogenetic, and functional similarity. In the present study we tested whether one stromal cell line could affect the intrinsic radiosensitivity of another. Two clonal stromal cell lines, which display distinct gamma-irradiation responses relative to dose rate were used: KM 101, which shows the same radiosensitivity at a low dose rate of 5 cGy/min (LDR) and a high dose rate of 120 cGy/min (HDR) and KM 104 which shows significant gamma-irradiation resistance at LDR. To facilitate the study of the gamma-irradiation response of each cell line during cocultivation, we derived stable subclones of each, expressing the transfected neomycin resistance (neo-r) gene, which confers resistance to the neomycin analog: G 418. Introduction of the neo-r gene did not alter cell lines radiosensitivity. The results show that cocultivation of stromal cell lines before, during, and after gamma-irradiation induces changes in repair of radiation-induced damage, with a dominant effect of a resistant cell line at LDR. In fact, the radiation survival curves of cocultivated stromal cell lines were always characteristic of KM 104, and a dose rate effect was observed, even when KM 101 was present in large excess. Moreover, our results are consistent with preferential killing of the more radiosensitive stromal cell line: both LDR and HDR Do values of the neo-r KM 101, cocultivated with the parent KM 104 for 24 hr before, and during gamma irradiation were significantly lower compared to the neo-r subclone irradiated alone. The LDR Do value of the neo-r KM 104 cocultivated for 24 hr before, and during gamma irradiation with excess of parent KM 101, was significantly higher, compared to the neo-r cells irradiated alone.

Bone Marrow↗