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J Fujimoto

Publications and source records attributed to J Fujimoto.

At least 325 records · Page 18Linked to original sources
PubMed1986

Human T lymphocytes and monocytes bear the same Leu-3(T4) antigen.

An analysis of the cellular distribution, biosynthesis, and structure of the human T lymphocyte antigen Leu-3(T4) was performed. By using a sensitive ELISA as well as FACS analysis, relative quantities of the Leu-3(T4) antigen from whole cell lysates and from cell surfaces of six cell lines were determined. The T-T hybrid cell line 255.88, and the monocyte/macrophage cell line U937, proved to be high producers of the antigen and were chosen for additional investigation. The Leu-3(T4) antigens from the T lymphocyte cell line and the monocyte/macrophage cell were shown to be identical by SDS-PAGE. Leu-3(T4) was a polypeptide of 55,000 AMW under reducing conditions, and 63,000 AMW under nonreducing conditions. In the 255.88 cell line, a second band of 41,000 AMW was associated with the true Leu-3(T4) molecule. The 55,000 AMW Leu-3(T4) molecule was shown to possess a high mannose sugar side chain, and to contain few accessible tyrosine residues. These studies demonstrate that human T lymphocytes and monocytes produce and process similar molecules that react with the anti-Leu-3(T4) monoclonal antibody. They also characterize this important associative antigen recognition structure and suggest that cells other than the T lymphocyte may be targets for the retrovirus HTLV-III.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1986

Huge intraabdominal fibromatosis on the posterior wall of uterus: a case report.

A patient with a huge intraabdominal fibromatosis connected by a pedicle to the posterior wall of the uterus is described. The blood supply to the tumor was exclusively from the uterus. CA 125 antigen in the patient's serum was elevated. The origin of the tumor is unknown but possibly from non-specific fibrous stroma in the uterus or peritoneum. We measured steroid receptors in the tumor and related tissues (peritoneum and cultured peritoneal fibroblasts), for information on steroid activity.

Adult↗
PubMed1986

Gestrinone (R2323) binding to steroid receptors in human uterine endometrial cytosol.

To understand the mechanism of biological action of gestrinone (R2323), which has a therapeutic effect against endometriosis, the binding of gestrinone to numerous classes of intracellular steroid binding proteins was studied in the human uterine endometrium. Gestrinone bound to endometrial receptors for estrogen, progesterone and androgen, but seemed not to bind to endometrial intracellular corticosteroid-binding globulin and sex hormone-binding globulin. Gestrinone occupies all specific binding sites of steroids in the steroid target cells despite the presence of endogenous steroids. It is speculated that the binding behavior of gestrinone may be related to its therapeutic effect on endometriosis. Gestrinone's more avid affinity for estrogen receptor may be the reason for the ability to use a lower clinical dose of gestrinone.

Cytosol↗
PubMed1986

Steroid receptors in uterine cervical cancers.

In cervical cancers, the estrogen receptor (ER) and progestin receptor (PR) were characterized in the cytosol protein. Receptor levels were determined in cytosol, nuclear KCl extract, and nuclear KCl unextractable fraction in various cervical cancer tissues. The androgen receptor (AR) was also similarly characterized. In the cytosol, the estrogen (E2)-ER complex and the promegesterone (R5020)-PR complex were sedimented at approximately the 5S and 8S or the 4S and 8S regions, respectively, by 5-20% linear sucrose gradient centrifugation. A steroid specificity study showed the presence of an estrogen-specific and a progestin-specific binder. The dissociation constant of the specific binder for estrogen (ER), progestin (PR), or androgen (AR) was approximately 10(-10) to 10(-9)M in cytosol, nuclear KCl, and nuclear KCl unextractable fraction in detected cases. Levels were determined by Scatchard analyses, using the dextran-coated charcoal (DCC) adsorption method for the former two and the washing method for the latter one. ER, PR, or AR was detected in some cases of determined cervical cancers (27 cases of squamous cell carcinoma, and 7 cases of adenocarcinoma); regardless of the histological types, ER was detected in almost all cases. PR was not detected in the given cases of cervical adenocarcinoma. It is suggested that estrogen stimulation of PR synthesis in cervical adenocarcinoma may be damaged.

Adenocarcinoma↗
PubMed1986

Cellular existence of estrogen receptor in C3H mouse mammary tumor.

Estrogen receptor (ER) in the C3H mouse mammary tumor was characterized in the cytosol and determined in the nuclear KCl extract and the nuclear KCl unextractable fraction (non-extract). In the cytosol, the estradiol (E2)-ER complex was sedimented in the 8S region by 5-20% linear sucrose gradient centrifugation. A steroid specificity study showed the presence of estrogen-specific binder with a dissociation constant (Kd) of approximately 2 nM. ER levels in the cytosol, the nuclear KCl extract, and the suspension of nuclear KCl unextractable fraction were determined by Scatchard analyses, using the dextran-coated charcoal (DCC) adsorption method for the former two and the sedimentation method for the latter. Although ER was present in the nuclear fractions, it seems more plausible that cytosol ER contributes to nuclear translocation of the estrogen-ER complex. The results suggest the presence of an intranuclear mechanism for the estrogen action.

Animals↗
PubMed1985

[The relationship between changes of the steroid receptor and synchronization in human adenocarcinoma cells in vitro of the endometrium].

We investigated the G1 and S phases of synchronization using sodium n-butyrate, MTX and excess thymidine. The flow cytometry system was employed for cell cycle analysis while the receptor assay was adopted dextran coated charcoal (DCC) and the wash method. The results were as follows: S phase synchronization by MTX was 138% (control 100%) and by excess thymidine in the block and release method 210%. G1 phase synchronization by sodium n-butyrate was 140%. The progesterone receptor level, by E2 priming increased to 1.45 fmol/ug DNA being more than five times that of the control PR. The estrogen receptor level increased to 18.29 fmol/ug DNA in the G1 phase synchronization, seven times that of the control ER. From this study, the functional increase of the steroid receptor was most significant in the G1 phase.

Adenocarcinoma↗
PubMed1985

Comparison of cellular levels of steroid receptors in uterine leiomyoma and myometrium.

To support the estrogen hypothesis in the pathogenesis of leiomyoma, total cellular estrogen receptor (ER) levels (the sum of levels in cytosol and nuclear KCl-extractable and nuclear non-KCl-extractable fractions) were assayed and compared with levels of progestin (PR) and androgen (AR) receptors in the leiomyoma and the corresponding myometrium. The ratios of ER to PR or AR levels were higher (with statistical significance) in leiomyoma than in the corresponding normal myometrium, both in terms of total cellular levels in each individual case and nuclear levels. It appears that estrogen sensitivity is higher in the leiomyoma than in the corresponding myometrium, due to the relative increase in ER.

Adult↗
PubMed1985

A novel human B-lymphocyte antigen shared with lymphoid dendritic cells: characterization by monoclonal antibody.

A novel cell-surface antigen (L25) expressed on human B cells was identified using a B cell-reactive monoclonal antibody (TB1-4D5). This L25 antigen was expressed on most B-lineage cells but not other cell types including thymocytes, T cells, granulocytes and monocytes. Thus, L25 existed on the majority of normal B cells present in the blood and lymphoid tissues, on cultured cell lines derived from normal and malignant B cells, and on neoplastic cells isolated from patients with B cell-derived malignancies. Though L25 was persistently expressed on B cells until 7 days after their activation with pokeweed mitogen (PWM), neither normal nor neoplastic plasma cells expressed L25. Moreover, L25 was present on cultured as well as freshly isolated leukaemic cells with common acute lymphatic leukaemia (CALL) antigen, which have been thought to correspond to the early B-cell ontogeny. Besides pan-B cell reactivity of TB1-4D5 antibody, it apparently cross-reacted with so-called dendritic or interdigitating cells located in the thymic-dependent areas of peripheral lymphoid organs, which have been presumably ascribed to those associated with accessory-cell function. Functional studies showed that anti-L25 (TB1-4D5) antibody had inhibitory effect on induction of immunoglobulin synthesis by PWM-stimulated B cells.

Antibodies, Monoclonal↗
PubMed1984

Immunochemical analysis of the released Leu-2 (T8) molecule.

We recently have found that the human T cell antigen Leu-2 was specifically released from Leu-2-bearing cells. The preliminary study showed that the released Leu-2 (RLeu-2) from HPB-ALL cells was composed of a single polypeptide chain of 27,000 molecular weight (mol wt), which was smaller than the subunit of the homodimeric molecule found on the cell surface. In the present study, RLeu-2 was further characterized and compared with cellular Leu-2 (CLeu-2). Metabolically radiolabeled Leu-2 was released from HPB-ALL cells and this released Leu-2 molecule had a mol wt of 27,000. Cell surface radioiodinated HPB-ALL cells were found to release radioactive Leu-2 molecules and this antigen also had the same mol wt of 27,000. In both experiments, the CLeu-2 was reconfirmed to be composed of a 33,000-mol wt subunit under reducing conditions. These experiments establish that the 27,000-mol wt single polypeptide chain of Leu-2 released from the cell is derived directly from the homodimeric Leu-2 molecule on the cell surface, presumably by a specific proteolytic cleavage. Two-dimensional gel analysis showed that CLeu-2 exhibited extensive charge heterogeneity with predominantly basic isoelectric points, whereas RLeu-2 was a group of more acidic proteins with less charge heterogeneity. Although CLeu-2 and RLeu-2 showed several different immunochemical characteristics, the homology between these two antigens was confirmed by the following results: CLeu-2 and RLeu-2 were found to share at least three different antigenic determinants, Leu-2a and Leu-2b, and those which were detected by a polyvalent rabbit antiserum. Significant similarities between CLeu-2 and RLeu-2 were demonstrated by peptide mapping analysis of these antigens. Therefore, RLeu-2 appears to be the specific, physiological product of the CLeu-2 protein.

Animals↗