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Biomedical subjects

N Yanai

Publications and source records attributed to N Yanai.

At least 91 records · Page 5Linked to original sources
PubMed1994

Induction of tumor necrosis factor in mice by recombinant human macrophage colony-stimulating factor.

The effect of recombinant human macrophage colony-stimulating factor (rhM-CSF) on endogenous production of tumor necrosis factor (TNF) was investigated in mice. The intravenous injection of lipopolysaccharide (LPS) after the administration of rhM-CSF via the same route induced the production of endogenous cytotoxic activity in serum as assessed by using TNF-sensitive murine L929 cells. The intravenous injection of LPS alone or rhM-CSF alone did not induce cytotoxic activity. The priming effect of rhM-CSF was transient and the optimal duration between injections of primer and trigger was 3 h, while the optimal duration between trigger injection and serum sampling was 1 h after LPS injection. Moreover, preinjection of rhM-CSF enhanced the priming effect of recombinant mouse interferon-gamma. No triggering effect of rhM-CSF was observed. The cytotoxic activity in the serum was completely neutralized by anti-mouse TNF-alpha polyclonal antibody. These results indicate that rhM-CSF can be used as a priming agent for endogenous production of TNF in vivo, and raise the possibility of using rhM-CSF in cancer immunotherapy.

Animals↗
PubMed1994

Proteoglycan form of macrophage colony-stimulating factor binds low density lipoprotein.

We recently isolated a proteoglycan form of macrophage colony-stimulating factor (PG-M-CSF) that carries a chondroitin sulfate glycosaminoglycan chain. Here, we examined the interaction of PG-M-CSF with low density lipoprotein (LDL). When LDL preincubated with PG-M-CSF was fractionated by molecular size sieving chromatography, it was eluted earlier than untreated LDL. When LDL was preincubated with chondroitin sulfate-free 85-kD M-CSF instead of PG-M-CSF, the elution profile of LDL remained unchanged, indicating specific interaction between PG-M-CSF and LDL. The level of PG-M-CSF binding in the wells of a plastic microtitration plate precoated with LDL was significant, this binding being completely abolished by pretreatment of PG-M-CSF with chondroitinase AC, which degrades chondroitin sulfate. The addition of exogenous chondroitin sulfate or apolipoprotein B inhibited the binding of PG-M-CSF to LDL in a dose-dependent manner, indicating that the interaction between PG-M-CSF and LDL was mediated by the binding of the chondroitin sulfate chain of PG-M-CSF to LDL apolipoprotein B. PG-M-CSF was also demonstrated in the arterial wall, and there were increased amounts of PG-M-CSF in atherosclerotic lesions. The in vitro interaction between PG-M-CSF and LDL thus appears to have physiological significance.

Aorta↗
PubMed1993

Erythropoietin as a mitogen for fetal liver stromal cells which support erythropoiesis.

Fetal liver stromal cells established from 13-day-old embryos support erythropoiesis in vitro in combination with erythropoietin (Epo). Epo stimulated growth of these stromal cells in a dose-dependent manner and mRNA for Epo receptor was detected. These results suggest the possible involvement of Epo in the generation of the fetal erythropoietic microenvironment during development.

Animals↗
PubMed1992

Biological activity of a proteoglycan form of macrophage colony-stimulating factor and its binding to type V collagen.

Two different types of macrophage colony-stimulating factors (M-CSF) were found, one with an apparent molecular mass of 85 kDa and the other greater than 200 kDa. The high molecular mass M-CSF was identified as a proteoglycan carrying chondroitin sulfate glycosaminoglycan and was designated as the proteoglycan form of M-CSF (PG-M-CSF). In this study, we compared the biological activity of the 85-kDa M-CSF and PG-M-CSF and examined the binding properties of these two M-CSF to certain extracellular matrix proteins, i.e. types I-V collagen and fibronectin, using a modified enzyme-linked immunosorbent assay. PG-M-CSF was capable of supporting the formation of murine macrophage colonies, and pretreatment of PG-M-CSF with chondroitinase AC, which degrades chondroitin sulfate, did not alter its colony-stimulating activity. The specific activity of PG-M-CSF was similar to that of the 85-kDa M-CSF. The 85-kDa M-CSF had no apparent affinity for the extracellular matrix proteins examined, whereas PG-M-CSF had an appreciable binding capacity to type V collagen, but did not bind to types I, II, III, and IV collagen or to fibronectin. Pretreatment of PG-M-CSF with chondroitinase AC completely abolished the binding of the species to type V collagen. Addition of exogenous chondroitin sulfate inhibited the binding of PG-M-CSF to type V collagen in a dose-dependent manner. These data indicated that the interaction between PG-M-CSF and type V collagen was mediated by the chondroitin sulfate chain of PG-M-CSF. PG-M-CSF bound to type V collagen could stimulate the proliferation of bone marrow macrophages, indicating that the matrix protein-bound PG-M-CSF retained its biological activity. This interaction between PG-M-CSF and type V collagen implies that the role of PG-M-CSF may be distinct from that of 85-kDa M-CSF.

Animals↗
PubMed1992

Identification of a high molecular weight macrophage colony-stimulating factor as a glycosaminoglycan-containing species.

Chinese hamster ovary cells transfected with a 4.0-kilobase macrophage colony-stimulating factor (M-CSF) cDNA express two different M-CSF species; one has an apparent molecular weight of 85,000 and is identified as a homodimer of a 43-kDa subunit, and the other has an indeterminate structure greater than 200 kDa. In this study, we investigated the structure of the high molecular weight M-CSF by immunochemical procedures. The high molecular weight M-CSF was easily purified, since it bound tightly to DEAE-Sephacel and eluted at a characteristically high salt concentration. The high molecular weight M-CSF migrated as a diffuse band of over than 200,000 on nonreducing sodium dodecyl sulfate-polyacrylamide gels. Analysis of the same samples under reducing conditions revealed that the larger species consisted of a heteromer of the 43- and 150-200-kDa M-CSF subunits. Digestion of the 150-200-kDa M-CSF subunit with chondroitinase, which degrades the chondroitin sulfate glycosaminoglycan chain, yielded a 100 kDa band. This species was secreted instead of 150-200-kDa species when the cells were cultured in the presence of beta-D-xyloside, which inhibits the elongation of the chondroitin sulfate glycosaminoglycan chain in proteoglycans, providing additional evidence for the existence of a chondroitin sulfate chain in the 150-200-kDa M-CSF subunit. Removal of O- and N-linked carbohydrate from the 150-200-kDa subunit yielded a polypeptide chain with a larger molecular mass (approximately 45 kDa) than that of the 43-kDa subunit (approximately 25 kDa). Collectively, these results indicate that the 150-200-kDa M-CSF subunit is a proteoglycan with a core protein that may be an alternatively processed form of M-CSF.

Animals↗
PubMed1992

Combined action of c-kit and erythropoietin on erythroid progenitor cells.

Mutations at the murine dominant-white spotting locus (W) (c-kit) affect various aspects of hematopoiesis. We have made antibodies against c-Kit with the synthetic peptides deduced from the murine c-kit gene and examined the role of c-Kit in erythropoiesis. The antibody inhibited the stromal cell-dependent large colony formation of the erythroid progenitors. In the culture of erythropoietin-responsive erythroid progenitors of the anemia-inducing Friend virus-infected mouse spleen, the antibody inhibited only proliferation, but not differentiation of the progenitor cells. The inhibition was effective only at the early phase (within 6 hours after erythropoietin addition) before the cells start to proliferate induced by erythropoietin. During the early phase, erythropoietin down-regulated c-kit gene expression. These results suggest a mechanism of combined action of c-Kit with erythropoietin on the lineage-restricted erythroid progenitor cells.

Animals↗
PubMed1992

The value of an electronic microcomputerized basal body temperature measurement device (Bioself) in in vitro fertilization cycles.

The Bioself 110 electronic basal body temperature (BBT) measurement device was employed in 18 women undergoing in vitro fertilization (IVF). This microcomputer-operated device records, charts and accurately analyzes the mean temperature measurements. These temperature recordings were used in addition to transvaginal ovarian sonography and serum estradiol and progesterone levels. The BBT rise correlated significantly (p < 0.0002) with progesterone elevation following human chorionic gonadotropin (hCG) administration. It is suggested that this electronic device may be used as an additional tool in the detection of premature progesterone secretion in IVF cycles.

Body Temperature↗
PubMed1992

[Thallium-201 and gallium-67 scintigraphies in the diagnosis of pneumoconiosis combined with lung cancer].

Thallium-201 (201Tl) and Gallium-67 (67Ga) scintigraphies were performed on 62-year-old male with silicosis combined with lung cancer (squamous cell carcinoma). In 67Ga and early 201Tl images, radiotracer uptakes were observed in both sites of cancer and silicosis, and thus, it was impossible to differentiate cancer mass from the large opacity of pneumoconiosis. On the other hand, in the 201Tl delayed images, 201Tl was localized only in cancer mass, while it was washed out from the large opacity. Our findings indicated that 201Tl early and delayed scintigraphy findings were very useful to differentiate lung cancer from silicosis.

Carcinoma, Squamous Cell↗
PubMed1991

Support of early B-cell differentiation in mouse fetal liver by stromal cells and interleukin-7.

We compared the development of B-cell progenitors with that of myeloid progenitors in fetal liver cells at various gestational ages. Day 12 to 14 fetal liver cells did not form pre-B-cell colonies. Pre-B-cell colonies were developed from day 15 fetal liver cells. The incidence of colonies increased with increases in gestational age and reached a maximum on days 18 to 19. In contrast, the incidence of myeloid colonies formed in the presence of interleukin-3 (IL-3) and erythropoietin did not change significantly during days 13 to 21 of gestation. After coculturing day 13 fetal liver cells with IL-7-producing stromal cell line ST-2, they could respond to IL-7 and proliferate. Analysis of the phenotypes showed that day 13 fetal liver cells were B220-, IgM-, while culturing day 13 fetal liver cells with ST-2 and untreated day 18 fetal liver cells contained the population of B220+ cells. Even in the presence of IL-7-defective stromal cell line FLS-3, IL-7-responsive cells could be induced from day 13 fetal liver cells. IL-7 acted on B220+ cells and induced pre-B-cell colonies that contained IgM+ cells in the methylcellulose culture. IL-7 mRNA was expressed in days 13 and 18 fetal liver cells but not in pre-B cells or adult liver cells. From these findings, it is suggested that stromal cells or stromal-derived factors but not IL-7 were required for the differentiation from B220- cells to B220+ cells. In the second stage, B220+, IgM- cells proliferated and some of them differentiated to IgM+ cells in the presence of IL-7 alone. The two-step model can apply to in vivo early B lymphopoiesis.

Animals↗
PubMed1991

Characterization of macrophage colony-stimulating factor in body fluids by immunoblot analysis.

We characterized the molecular species of human macrophage colony-stimulating factor (hM-CSF) found in serum and urine, using immunoblot analysis after partial purification on an antibody-bound affinity column. Although antibodies were prepared using the recombinant product of the large form of hM-CSF with a molecular weight (MW) of 85 Kd as the antigen, this immunoblot system was also capable of detecting the small form of hM-CSF with a MW of 40 to 60 Kd. A single band with a MW of 43 Kd, which reacted with anti-recombinant hM-CSF IgG but not with control IgG, was found when serum and urine from normal adults underwent electrophoresis on reduced sodium dodecyl sulfate-polyacrylamide gel and subsequent immunoblotting. This band represented a subunit of the large form of hM-CSF, because the large form of hM-CSF is a homodimer of a subunit with a MW of 43 Kd and the small form of hM-CSF is a homodimer of a subunit with a MW of 20 to 30 Kd. Analysis of serum and urine from leukemic patients and pregnant women, who had higher serum levels of hM-CSF than normal adults, showed only a single band with a MW of 43 Kd as a hM-CSF-specific molecule. These results suggest that the large form of hM-CSF is the major species in human body fluids.

Body Fluids↗
PubMed1991

Continued blood cell formation in spherical bodies in a long-term mouse spleen culture.

During the primary culture of spleen fragments of newborn mice, a spherical body (d = circa 200 to 300 microns) as a three-dimensional cellular organization was formed. Continued production of blood cells from the spherical body was observed without changing its size for about 2 months of culture. Without growth factor, the spherical bodies produced mainly lymphocytes and macrophages. Addition of interleukin-3 enhanced their granulocyte formation, and this enhancement was observed even after a prolonged maintenance without growth factors. The spherical bodies were composed of a uniform mixture of endothelial cells and fibroblasts within the body, and cell-cell contacts between lymphocytes and fibroblasts were notable in the periphery. With prolonged culture, the spherical bodies showed a definite change in their structure by sorting two cell types and the blood cell production gradually decreased. These results suggested that a three-dimensional structure was required for the maintenance, growth, and differentiation of blood cell progenitors in the long-term spleen culture.

Animals↗
PubMed1991

Hepatocyte cell lines established from transgenic mice harboring temperature-sensitive simian virus 40 large T-antigen gene.

To establish cell lines exhibiting differentiation phenotypes, the immortalized cell lines were rapidly established from the primary culture of different tissues of transgenic mice harboring SV40 temperature-sensitive large T-antigen gene. The established cell lines grew at permissive temperature (33 degrees C), but not at nonpermissive temperature (39 degrees C). Several different cell types could be rapidly immortalized and cloned from the adult transgenic mice tissues. Among those cell lines, the established hepatocyte cell lines (TLR cell lines) exhibited liver-specific morphological and biochemical properties, but their properties were not coupled with the growth condition modified by temperature. The hepatocyte cell lines showed an inducibility of P450IA1 by 3-methylcholanthrene as observed in rat livers and this liver-specific function was stable even after 6 months of culture by continuous passages.

Animals↗
PubMed1991

A tubule cell line established from transgenic mice harboring temperature-sensitive simian virus 40 large T-antigen gene.

Immortalization of cell lines with specific functions is important for examination of organ-specific functions in vitro. We established a kidney tubule cell line (TKC2) exhibiting a specific physiological response to hormone from the primary culture of kidneys of adult transgenic mice harboring temperature-sensitive SV40 large T-antigen gene. TKC2 cells showed temperature-sensitive growth in culture and exhibited characters of distal tubule cells such as dome formation at confluent culture and stimulation of cAMP synthesis by arginine vasopressin. These phenotypes are maintained after long passages in culture and may provide a new experimental system for studying renal physiology.

Animals↗
PubMed1991

Endothelial cells create a hematopoietic inductive microenvironment preferential to erythropoiesis in the mouse spleen.

The spleen is an erythropoietic organ in mouse. To reconstruct a microenvironment essential for erythropoiesis in vitro, the stroma (MSS31) cell line had been established from a newborn mouse spleens. MSS31 cells exhibited properties of endothelial cells: (a) the cells showed the activity to uptake acetylated low-density lipoprotein (Ac-LDL) and (b) the cells can form a capillarylike structure by a phenotypic modulation in collagen matrices. MSS31 cells selectively supported the proliferation and differentiation of the erythroid progenitor cells by direct cell-to-cell contact in a semisolid medium in the presence of erythropoietin. These layers also supported erythrocyte maturation and enucleation of erythroblasts. This suggests that spleen endothelial cells are a new type of stromal cell with erythropoietic stimulation activity and may have a critical function in the hemopoietic inductive microenvironment of the mouse spleen.

Animals↗
PubMed1991

Sonography-guided fetal blood sampling for pH and blood gases in premature fetuses with abnormal fetal heart rate traces.

In nine pregnancies, remote from term, with an abnormal Non-Stress Test (NST) and Bio-Physical Profile (BPP) of 3 or above, cordocentesis for fetal blood gas analysis was performed. In seven cases an immediate post-partum blood sample was taken from the fetal cord for a similar analysis. The two tests gave very similar results. The results showed fetal acidemia (pH 7.09-7.19 and B.E. -10-15) in 4 cases, followed by immediate delivery. In the remaining 5 cases, normal blood gases were evident (pH 7.28-7.35); despite the abnormal NST, pregnancy was allowed to continue for 2 to 7 weeks, under close supervision. At birth, 2 out of 9 newborns were deemed by the neonatologist suffering from asphyxia. Both belonged to the acidemic group of women who were managed by immediate cesarean section. The other 5 fetuses, which were managed expectantly, had normal post-partum blood gases or Apgar score; none had asphyxia. Fetal blood gas analysis, on samples obtained by cordocentesis, provides useful information that can assist in the management of premature fetuses suspected of being distressed, according to their heart traces. Normal fetal blood gases can identify those fetuses falsely identified by the NST as in distress and thereby spare them unnecessary premature birth with its known complications.

Acidosis↗
PubMed1990

Differentiation-dependent expression of I and sialyl I antigens in the developing lung of human embryos and in lung cancers.

The localization of two carbohydrate antigens, I and sialyl I antigens, in the lungs of developing human embryos was investigated using specific monoclonal antibodies and compared with the distribution patterns of the known embryonic antigen, stage-specific embryonic antigen-1 (Lex hapten). When the future bronchi were actively developing from the bronchial buds in the lungs of 50- to 53-day-old embryos, the immature bronchial bud cells were I-, Lex+, while the fully differentiated epithelial cells of the larger bronchus were I+, Lex-. When the bronchiolar bud cells matured into bronchiolar epithelial cells in the lung of a 12-week-old embryo, the immature bronchiolar bud cells were I-,Lex+, while the fully differentiated epithelial cells of the bronchioles were I+,Lex-. Sialylated forms of the antigens finally appeared in the lungs of 18-week-old embryos, when the terminal bud cells actively proliferated and underwent the differentiation process into epithelial cells of alveoli and alveolar ducts. The immature terminal bud cells at this stage were I-, sialyl I-, Lex+, sialyl Lex-i+, while the fully differentiated alveolar epithelial cells were I+, sialyl I+, Lex-, sialyl Lex-i-. After 8 months, the flattened mature alveolar epithelial cells were strongly positive for both I and sialyl I antigens, the strong expression of which continued after birth and even into the adult stage. These distribution patterns indicate that the I and sialyl I antigens are specific markers for the differentiated type cells in each stage of development, while Lex and related embryonic antigens were specific to the immature bud cells in every stage. The above-described differentiation-dependent expression patterns of these antigens seem to be reflected in the distribution of these antigens in human lung cancers, i.e., I and sialyl I antigens were expressed in lung cancer cells more weakly than in normal lung cells, while the Lex and sialyl Lex-i were expressed in cancer cells much more strongly than in normal lung cells. This was further reflected in the serum levels of these antigens in the patients with respiratory disorders. The distribution pattern of the serum levels of these antigens in patients with lung cancers showed sialyl Lex-i greater than sialyl I, indicating that these serum antigens originated from the lung cancer lesion where sialyl Lex-i is much more dominant than sialyl I antigen.(ABSTRACT TRUNCATED AT 400 WORDS)

Adenocarcinoma↗
PubMed1990

Enhancement of the antibody-dependent tumoricidal activity of human monocytes by human monocytic colony-stimulating factor.

Human monocytic colony-stimulating factor (hM-CSF) stimulates mature cells as well as progenitor cells of human monocyte lineage. In the present study, we investigated the effect of completely purified native hM-CSF on the tumoricidal activity of human monocytes against Raji (Burkitt lymphoma-derived cell line) using a chromium release assay. Preincubation of human peripheral blood monocytes with hM-CSF for 48 h markedly enhanced their antibody-dependent cellular cytotoxicity (ADCC). This enhancing effect was dependent on the concentration of hM-CSF, and maximal enhancement was achieved at the concentration of 66 ng/ml. The number of receptor sites on monocytes against the Fc portion of immunoglobulin G increased 2- to 4-fold during 48 h incubation with hM-CSF. These results suggest that hM-CSF stimulates monocyte-ADCC by increasing the number of Fc receptor sites on human monocytes.

Antibody-Dependent Cell Cytotoxicity↗