PubMed Health⌕ Search

Biomedical subjects

A Kukita

Publications and source records attributed to A Kukita.

At least 19 recordsLinked to original sources
PubMed1999

A novel role of IL-15 in the development of osteoclasts: inability to replace its activity with IL-2.

IL-15 shares many activities with IL-2 on stimulating lymphocytes, hematopoietic progenitor cells, and macrophages. However, the role of IL-15 in osteoclastogenesis has not been elucidated. The recent finding of abundant IL-15 in rheumatoid arthritis synovial fluids suggested a possible role for this cytokine in the pathological destruction of bone and prompted us to determine whether IL-15 stimulates osteoclast formation. IL-15 stimulated the formation of multinucleated osteoclast-like cells in rat bone marrow cultures. In stroma-free cultures, IL-15 increased the number of mononuclear preosteoclast-like cells in the early stage of osteoclast formation. The stimulation was observed even after treatment with IL-15 for only 24 or 48 h of culture. Moreover, low IL-15 concentration (0.1 ng/ml) strongly increased the level of calcitonin receptor mRNA of mononuclear preosteoclast-like cells. Although IL-15 is known as a potent stimulator of TNF-alpha, its activity was not abolished by addition of anti-TNF-alpha Ab. Interestingly, IL-2 and IL-7, which utilize some IL-15R components, had no effect on osteoclast differentiation, but pretreatment with IL-2 or IL-7 of bone marrow cells before the addition of IL-15 inhibited the enhancing activity of IL-15. In summary, IL-15 has a novel activity to stimulate the differentiation of osteoclast progenitors into preosteoclasts, which cannot be replaced by IL-2 but may use components in common with IL-2R to mediate its effects.

Animals↗
PubMed1998

Laminin, a major basement membrane component of the blood vessel, as a negative regulator of osteoclastogenesis.

Laminin, the major basement membrane glycoprotein of the blood vessel, inducing many cellular responses, inhibited the differentiation of osteoclasts in a rat bone marrow culture system when immobilized on the surface of the culture wells, showing that laminin acts as a negative regulator of osteoclast differentiation in a nonsolubilized form. Laminin inhibited the process of preosteoclast formation from early progenitor cells in bone marrow. This laminin-mediated inhibition of osteoclastogenesis was blocked by the addition of laminin fragment YIGSR, indicating that the inhibitory effect of laminin was mediated via laminin receptors. This finding suggests a significant role of basement membrane laminin of the blood vessels as a negative regulator of osteoclastogenesis.

Acid Phosphatase↗
PubMed1998

Successful detection of active osteoclasts in situ by systemic administration of an osteoclast-specific monoclonal antibody.

Cell-surface proteins preferentially expressed on osteoclasts are thought to play important roles in the functional modulation of the osteoclasts. Recently, we found a novel cell-surface antigen designated Kat1-antigen (Kat1-Ag) specifically expressed on rat osteoclasts. It would be useful to regulate the functional activity of the osteoclasts directly via an osteoclast-specific antigen expressed on the cell surface of the osteoclasts. In order to establish the basis of such an application, in the present study we established a method for the direct detection of osteoclasts in situ by a systemic administration of the anti-Kat1-Ag monoclonal antibody (mAb Kat1) to rats, and we successfully detected functional osteoclasts in situ. Prior to performing in vivo experiments, we examined the reactivity of the mAb Kat1 to the isolated rat osteoclasts. Approximately 40-80% of the osteoclasts were reactive with mAb Kat1, suggesting that this mAb recognizes osteoclasts in a specific differentiation or functional state. Calcitonin treatment of osteoclast-like cells formed in vitro from bone marrow cells resulted in a conversion of Kat1-positive osteoclast-like cells into Kat1-negative multinucleated cells, showing the positive correlation between the Kat1-Ag expression and the potential bone-resorbing activity of osteoclasts. Administration of this lineage-specific mAb to the peritoneal cavity of newborn rats resulted in a successful recruitment of mAb Kat1 to the newly formed osteoclasts and functional osteoclasts in a highly specific manner. Detailed analysis by immunoelectron microscopy revealed that this mAb specifically bound to the basolateral side of the active osteoclasts, which were identified by their typical ruffled border and clear zone, whereas the mAb did not react to postfunctional osteoclasts. These findings demonstrate a high potential utility of mAb Kat1 in osteoclast-targeted regulation of bone remodeling.

Animals↗
PubMed1998

A large number of tandem repeats in the polymorphic epithelial mucin gene is associated with severe acne.

Polymorphic epithelial mucin (PEM) or MUC1 is a glycoprotein secreted from various epithelial gland tissues. In skin, PEM is detected in sweat glands and sebaceous glands by the DF3 monoclonal antibody. The gene of PEM includes an allele exhibiting length polymorphism due to a variable number of tandem repeats (VNTR); this is expressed co-dominantly, which may influence the microenvironment of the skin. The allelic size variation of the PEM gene was investigated in Japanese acne patients, atopic dermatitis patients, and healthy controls. The frequency of longer length alleles was significantly higher in severe acne patients.

Acne Vulgaris↗
PubMed1998

Involvement of lymphocyte function-associated antigen-1 and intercellular adhesion molecule-1 in osteoclastogenesis: a possible role in direct interaction between osteoclast precursors.

In our search for molecules involved in the process of osteoclast differentiation, we examined the surface phenotypes of the preosteoclast-like cells and osteoclast-like multinucleated cells (MNCs) formed in bone marrow cultures, using monoclonal antibodies recognizing different antigen molecules expressed on hematopoietic cells. Among these cell surface antigens, lymphocyte function-associated antigen-1 (LFA-1) and intercellular adhesion molecule-1 (ICAM-1) were highly expressed on mononuclear cells in the cultures for forming preosteoclast-like mononuclear cells. The double detection of these two antigen molecules with osteoclast-specific antigen and with calcitonin receptor, using a fluorescence-activated cell sorter or autoradiography technique, revealed that LFA-1 and ICAM-1 were expressed on the preosteoclasts. The expression of ICAM-1 was detected on both preosteoclasts and osteoclast-like MNCs, whereas the expression of LFA-1 was restricted to preosteoclasts. We designed a peptide with the sequence of the binding site of ICAM-1 against the ligand LFA-1. In the whole bone marrow culture system for forming osteoclast-like MNCs, a significant inhibition of MNC formation was observed by the addition of this peptide. These results strongly suggest the involvement of an LFA-1/ICAM-1-interaction in osteoclastogenesis.

Animals↗
PubMed1998

Cellulitis of the eyelids associated with sinusitis and brain abscess.

Erythema in the orbital area can indicate systemic and life-threatening diseases. We experienced an unusual and serious case of orbital cellulitis that was difficult to distinguish from a case with good prognosis. A 21-year-old man developed an erythema around his eyes. He exhibited no symptoms that would suggest lesions in deep tissues, but his condition turned out to be cellulitis retrogradely metastasized from an odontogenic sinusitis traced to a dental treatment problem. Computed tomography revealed complication of a large abscess in the frontal lobe. Cellulitis of the orbital area requires particular clinical discretion.

Adult↗
PubMed1997

Regulation of osteoclastogenesis by antisense oligodeoxynucleotides specific to zinc finger nuclear transcription factors Egr-1 and WT1 in rat bone marrow culture system.

Differentiation of osteoclasts is defined by the transcription factors expressed in response to bone microenvironments. In this work, we examined the effects of an expressional blockage of Egr-1 and/or WT1 on the differentiation of osteoclasts using specific antisense oligodeoxynucleotides (ODN). In a culture system forming preosteoclast-like cells (POC) from rat bone marrow cells depleted of marrow stromal cells, POC formation was markedly stimulated by the addition of Egr-1 antisense ODN compared to that in cultures in which sense ODN was added, whereas Egr-1 antisense ODN inhibited the formation of macrophage-like cells. The formation of multinucleated osteoclast-like cells was also stimulated by the addition of Egr-1 antisense ODN in whole bone marrow cultures. In contrast, WT1 antisense ODN did not affect POC formation induced by the treatment with Egr-1 antisense ODN; however, WT1 antisense ODN dramatically suppressed the formation of osteoclast-like multinucleated cells induced by the blockage of Egr-1 expression using Egr-1 antisense ODN. These data suggest that Egr-1 acts as the suppressor, not as the inducer, in osteoclastogenesis. The findings also suggested that WT1 could be involved in the multinucleation step of osteoclastogenesis, at least when Egr-1 expression was blocked.

Animals↗
PubMed1997

Macrophage inflammatory protein-1 alpha (LD78) expressed in human bone marrow: its role in regulation of hematopoiesis and osteoclast recruitment.

Human macrophage inflammatory protein-1 alpha (hMIP-1 alpha), also known as LD78, is a member of the chemokine/ intercrine family and an inhibitor of the proliferation of the hematopoietic stem cells in vitro. Using a specific monoclonal antibody, we observed significant localization of hMIP-1 alpha in eosinophilic myelocytes in human bone marrow. We further examined the expression of hMIP-1 alpha mRNA in human bone tissue by in situ hybridization. A high level of hMIP-1 alpha mRNA expression was detected in eosinophilic myelocytes in bone marrow, confirming these cells as the site of hMIP-1 alpha synthesis. hMIP-1 alpha mRNA expression was also detected in osteoblasts in the bone-remodeling sites, and osteoclasts were frequently observed in the vicinity of these osteoblasts. hMIP-1 alpha was also able to induce osteoclastogenesis on calcified matrices in the absence of any other osteotropic hormones. These results strongly suggest that hMIP-1 alpha is involved not only in the regulation of hematopoiesis but also in the modulation of bone remodeling.

Animals↗
PubMed1996

Alteration of human melanoma gangliosides by IFN-gamma, IL-2, and IL-4.

In lesions of malignant melanoma, melanoma cells are exposed to various cytokines produced by inflammatory reactions. As a result, transformation of melanoma cells is expected to occur. We studied alterations in human melanoma cell line ganglioside composition after exposing melanoma cell lines to interferon (IFN)-gamma, interleukin (IL)-2, and IL-4 by biochemical methods. IFN-gamma increases the ratio of a-series gangliosides and the ratio of GM3/GD3. This suggests an alteration of immunoreactivity, a decrease in ganglioside sialyltransferase II activity, and an decrease in the malignant character of these cells. The alteration of the ganglioside profile varied among cytokines and cell lines. The progression of malignant melanoma may be influenced by reciprocal interactions between the melanoma cells and the host immune system.

Gangliosides↗
PubMed1996

Osteoclast differentiation antigen.

Osteoclasts are the primary cells which perform bone resorption. The origin of these multinucleated giant cells is the haematopoietic stem cells. The differentiation pathway of the osteoclasts has so far been well studied and the cell-lineage of these bone resorbing cells is considered to be close but not identical to the monocytes/macrophages. Owing to the development of in vitro culture systems for evaluating osteoclast differentiation, it has been elucidated that various cytokines are involved in the differentiation of the osteoclasts. However, there is still ambiguity concerning the molecular mechanism of the differentiation of the osteoclasts. One approach for clarifying the molecular mechanism is to find unique antigen molecules involved in the process of osteoclast differentiation. In this review article, we introduce such immunological studies concerning osteoclast differentiation. We also refer to our recent establishment of a panel of monoclonal antibodies recognizing rat osteoclasts. One of the monoclonal antibodies recognizes cell surface antigen (Kat1-antigen) expressed on cells in osteoclast-lineage and not on monocytes/macrophages. Cross-linking of the cell surface antigen using this monoclonal antibody showed that the Kat1-antigen is the unique cell surface molecule involved in the regulation of the affinity of the calcitonin receptor and also involved in the modulation of bone resorption. In this review article, we overview, the current issues which should be elucidated for understanding the differentiation and activation of the osteoclasts. We further emphasize the utility of the immunological approach for solving these current target issues.

Animals↗
PubMed1995

Interleukin-10 selectively inhibits osteoclastogenesis by inhibiting differentiation of osteoclast progenitors into preosteoclast-like cells in rat bone marrow culture system.

Recombinant human interleukin-10 (hIL-10) inhibited the formation of osteoclast-like multinucleated cells in rat whole bone marrow cultures. The effect of hIL-10 on the process of osteoclast formation was further examined, since the process of osteoclast formation includes the proliferation and the differentiation of osteoclast progenitors into mononuclear preosteoclasts and the fusion of preosteoclasts into multinucleated osteoclasts. In the nonadherent bone marrow cell culture system, which was free of stromal cells and formed preosteoclast-like cells, hIL-10 significantly inhibited the formation of preosteoclast-like cells even at a very low concentration (0.5 U/ml). The strong inhibition appeared even after treatment with hIL-10 for only the first 24 h of the culture. However, hIL-10 did not affect the fusion process of preosteoclast-like cells to form osteoclast-like multinucleated cells in the rat coculture system of preosteoclast-like cells with primary osteoblasts. Furthermore, hIL-10 completely inhibited the colony formation induced by granulocyte macrophage colony-stimulating factor (GM-CSF). These findings suggest that the inhibition of osteoclastogenesis by hIL-10 started at the early stage of the differentiation of osteoclast progenitors to preosteoclasts.

Animals↗
PubMed1995

Intracellular multiplication of Legionella pneumophila in HL-60 cells functionally differentiated in response to 22-oxacalcitriol.

The agent 1,25-dihydroxyvitamin D3 (D3) induces the differentiation of HL-60 human leukemia cells into functional monocyte-like cells that can support the intracellular multiplication of Legionella pneumophila. 22-Oxacalcitriol (OCT), a synthetic analogue of D3, exhibits greater differentiation-inducing activity than D3 in WEHI-3 mouse leukemia cells and has been suggested to be clinically more useful because of its lower hypercalcemic activity. The abilities of OCT and D3 to induce the functional differentiation of human leukemia HL-60 cells have now been investigated. OCT induced the differentiation of HL-60 cells into monocyte-like cells to a similar extent as D3. Thus, both OCT and D3 increased (1) the surface expression of CD11b, CD11c, CD14, and CD35; (2) nonspecific esterase staining; and (3) phagocytic activity toward fluorescent beads. HL-60 cells differentiated in response to OCT also supported the intracellular multiplication of L. pneumophila. Activation of both OCT- and D3-treated HL-60 cells with human recombinant interferon-gamma (IFN-gamma) for 24 h before infection markedly inhibited L. pneumophila multiplication. IFN-gamma activation enhanced superoxide anion generation by D3-treated HL-60 cells but not by OCT-treated HL-60 cells, suggesting that the inhibition of L. pneumophila multiplication in IFN-gamma-activated cells is independent of superoxide generation. Finally, D3, but not OCT, markedly stimulated the formation of osteoclast-like multinucleated cells from mouse bone marrow cells, consistent with the lower hypercalcemic activity of OCT.

Animals↗
PubMed1995

In vitro differentiation of the murine macrophage cell line BDM-1 into osteoclast-like cells.

Osteoclasts are derived from hematopoietic stem cells, but details about their precursor are still obscure. We present here a mouse macrophage cell line, BDM-1 cells, that showed a high potential to differentiate into osteoclast-like multinucleate cells (MNCs) when cocultured with primary osteoblasts for 14 days in the presence of 10(-8) M 1 alpha,25-dihydroxyvitamin D3. These MNCs had tartrate-resistant acid phosphatase (TRAP) activity and strong ability to resorb dentine. In this culture system, 10(-10)-10(-8) M 12-O-tetradecanoylphorbol-13-acetate stimulated the formation of TRAP-positive MNCs, whereas salmon calcitonin inhibited it. Time-course effect studies showed that 12-O-tetradecanoylphorbol-13-acetate had an effect on the late phase of osteoclast differentiation but not on precursor proliferation. By immunocytochemical staining, all BDM-1 cells expressed Mac-1, Mac-2, and MOMA-2 antigens, and a large number of them expressed F4/80 antigen, but the rest of them were negative for this antigen. To select subclones able to differentiate into TRAP-positive MNCs, we sought to isolate several subclones from BDM-1 cells by mean of different specificity for F4/80 antigen expression. TRAP-positive MNCs were not generated from F4/80-positive subclones, but were obtained from subclones containing F4/80-negative cells. These results suggest that an F4/80-negative macrophage subpopulation is responsible for the differentiation of this cell line into osteoclasts.

Acid Phosphatase↗
PubMed1994

Novel cell-surface Ag expressed on rat osteoclasts regulating the function of the calcitonin receptor.

Osteoclasts are known to be hematopoietic in origin. However, the detailed mechanisms of their differentiation and activation are not known. Cell-surface molecules preferentially expressed on cells of the osteoclast lineage may play some important roles in these processes. We prepared a mAb that recognizes a unique cell-surface membrane protein specifically expressed on rat osteoclasts. Expression of this Ag, designated as Kat1 Ag, was markedly stimulated by a factor secreted by the osteoblastic cell line ROS 17/2.8. Binding studies of 125I-labeled calcitonin (CT) showed that the Ag was not the CT receptor (CTR). However, interestingly, studies of the biologic activity of this mAb that recognizes Kat1-antigen (mAb Kat1) revealed possible regulatory functions of this Ag in osteoclasts. Firstly, mAb Kat1 significantly elevated the binding affinity of the CTR expressed on osteoclast-like cells without altering the number of receptors. Secondly, CT-sensitivity of the osteoclast progenitor cells in the system of osteoclast differentiation showed marked augmentation on treatment of these cells with this mAb. Even a very low concentration of CT (0.1 ng/ml) significantly inhibited osteoclast differentiation in the presence of mAb Kat1, whereas a higher concentration of CT (10 ng/ml) was required to inhibit their differentiation in the absence of this mAb. Thirdly, mAb Kat1 inhibited dentin-resorbing activity of osteoclast-like cells. Furthermore, the inhibitory effects of CT on osteoclast-mediated dentin resorption was augmented by the presence of this mAb. These observations strongly suggest that Kat1-antigen is a unique cell-surface protein regulating the affinity of the CTR expressed on osteoclasts and also the bone-resorbing function of these cells.

Animals↗
PubMed1994

A novel monoclonal antibody recognizing a unique antigen of rat osteoclasts induced by the calcified matrices.

The morphology of osteoclasts, primary cells that resorb bone, is well documented; however, the precise details of their terminal differentiation remains obscure. To date, the only morphological criterion for identifying activated functional osteoclasts has been the presence of ruffled borders. We have developed a rat bone marrow culture system in which osteoclast-like cells formed. These cells fulfilled most of the criteria of osteoclasts, and when they were reseeded on calcified tissue, formed numerous resorption lacunae in vitro. To find an immunological marker for functional osteoclasts, we have used these cells in a functional state as antigens for the preparation of monoclonal antibodies (mAb) that reacted with rat osteoclasts; we obtained mAb Ch1 and Ch2. Interestingly, these mAbs reacted with the marginal portion of authentic osteoclasts, where they attached to the bone surface on frozen sections. The reactivity of Ch1 to rat osteoclasts was more restricted than that of Ch2: Ch1 reacted with few tartrate-resistant acid phosphatase (TRAP)-positive cells on a culture plate. These TRAP-positive cells (including mono- and multinucleated cells) were, however, converted to Ch1-positive cells when they were reseeded on calcified tissues. These findings suggested that the antigen recognized by the Ch1 antibody was induced by some factors of matrix proteins released from calcified tissues.

Acid Phosphatase↗
PubMed1994

Localization of osteopontin in resorption lacunae formed by osteoclast-like cells: a study by a novel monoclonal antibody which recognizes rat osteopontin.

The characteristics of a monoclonal antibody produced against osteoclast-like multinucleated cells (MNCs) formed in rat bone marrow cultures were examined immunohistochemically and biochemically. The in vitro immunization was performed using as immunogen the MNCs from rat bone marrow cell culture, which revealed many characteristics of osteoclasts. After screening and cloning of hybridomas, the monoclonal antibody HOK 1 was obtained. This antibody reacted weakly with stromal cells and intensely with both MNCs and their putative migratory traces on culture dishes. Immunofluorescent examination of paraffin sections revealed intense reactivity on the epithelium of the choroid plexus, the ileum and the proximal-convoluted tubules of the kidney, and also on bone cells such as osteocytes, osteoblasts, and osteoclasts. Western blotting using purified rat osteopontin verified that the antigen recognized by HOK 1 was osteopontin. Positive HOK 1 immunoreactivity was further observed in the resorption lacunae formed by a culture of MNCs on human tooth slices and on the surface of osteoclasts. The present data suggested that osteopontin is preferentially present on the resorption lacunae in resorbing calcified matrices and that osteoclasts under a specific state might trap this protein on their cell surface.

Animals↗
PubMed1994

Perforating lichen nitidus.

A 32-year-old man with no particular family history nor past history visited our clinic in September 1992, with papules that he claimed had developed approximately 3 years earlier. No subjective symptoms accompanied then. On examination, numerous, discrete, pinhead-sized or half-ricecorn-sized, flesh-colored papules were observed on the dorsolateral side of his left hand and fingers. No central dimple or scaling were noticed clinically (Fig. 1). Laboratory tests revealed no abnormal findings. The histopathology of the biopsied specimen showed a circumscribed nest of infiltrating cells closely attached to the epidermis (Fig. 2). These infiltrating cells consisted of mononuclear lymphoid cells and histiocytes. The overlying epidermis was stretched and atrophic. A transepithelial perforation channel existed in direct contact with the surface. Amorphous debris containing cell nuclei lay within the channel (Fig. 2). Lymphoid cells were also observed above the keratin layer overlying the channel. At the lateral margin of the infiltrate, rete ridges extended downward in the manner of a claw clutching a ball. In a periodic-acid-Schiff (PAS)-stained section, a basement defect was observed around the channel.

Adult↗