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Biomedical subjects

N Mukaida

Publications and source records attributed to N Mukaida.

At least 127 records · Page 7Linked to original sources

Intervention of crescentic glomerulonephritis by antibodies to monocyte chemotactic and activating factor (MCAF/MCP-1).

We investigated the pathophysiological role of a potent macrophage (M(phi)) chemotactic cytokine (chemokine), monocyte chemotactic and activating factor/monocyte chemoattractant protein-1 (MCAF/MCP-1), in an animal model of crescentic glomerulonephritis. Administration of a small dose of nephrotoxic sera induced severe proliferative and necrotizing glomerulonephritis, with crescentic formation in the early phase and glomerulosclerosis in the later phase, in Wistar-Kyoto rats. MCAF/MCP-1 protein was detected immunohistochemically in glomeruli, vascular endothelial cells, and tubular epithelial cells in the early phase of injured kidney tissues but not in normal ones. Anti-MCAF/MCP-1 antibodies decreased the number of M(phi) in glomeruli, and prevented crescentic formation and the fusion of epithelial cell foot process in nephritic rats, thereby decreasing the excreted amounts of protein to normal levels on days 3 and 6. Furthermore, anti-MCAF/MCP-1 antibodies remarkably reduced glomerulosclerosis and improved renal dysfunction as well as proteinuria in the later phase (56 days). These results indicate that MCAF/MCP-1 essentially participates in the impairment of renal functions associated with crescentic glomerulonephritis by recruiting and activating M(phi).

Animals↗

Recombinant human growth-regulated oncogene-alpha induces T lymphocyte chemotaxis. A process regulated via IL-8 receptors by IFN-gamma, TNF-alpha, IL-4, IL-10, and IL-13.

The human cytokine growth-regulated oncogene (GRO)-alpha is a small glycoprotein secreted by monocytes, endothelial cells, glycoprotein secreted by monocytes, endothelial cells, fibroblasts, synovial cells, and some tumor cells such as melanoma cells. It is structurally related to IL-8 and can activate neutrophils, whereas it induces chemotaxis, exocytosis, and a respiratory burst in neutrophils. To date, its functions on T lymphocytes have not been well established. We report here that recombinant human (rh)GRO-alpha is a potent chemoattractant for freshly isolated T lymphocytes, but not for anti-CD3 mAb-activated T lymphocytes. It attracts CD4+ and CD8+ T lymphocyte subsets to an equal extent. The migrating T lymphocytes toward rhGRO-alpha are predominantly CD45RO+ memory CD4+ and CD8+ subsets. The chemotactic migration of T lymphocytes toward rhGRO-alpha is stimulated via the IL-8 receptors on the cells. This process can be augmented by IFN-gamma and TNF-alpha, and inhibited by IL-4, IL-10, and IL-13. In addition, we also document that on T lymphocytes there exist IL-8 receptors that can be up-regulated by IFN-gamma, TNF-alpha, and IL-2. Our results demonstrate that rhGRO-alpha gene encodes for an inflammatory mediator that stimulates the directional migration of T lymphocytes. It may thus be another important mediator in the diseases in which T lymphocytes form the major constituent of the cellular infiltration.

Antigens, CD↗

Identification of an I kappa B alpha-associated protein kinase in a human monocytic cell line and determination of its phosphorylation sites on I kappa B alpha.

Nuclear factor kappa B (NF-kappa B) is stored in the cytoplasm as an inactive form through interaction with I kappa B. Stimulation of cells leads to a rapid phosphorylation of I kappa B alpha, which is presumed to be important for the subsequent degradation. We have recently reported the establishment of a lipopolysaccharide (LPS)-dependent cell-free activation system of NF-kappa B in association with the induction of I kappa B alpha phosphorylation. In this study, we have identified a kinase in cell extracts from the LPS-stimulated human monocytic cell line, THP-1, that specifically binds and phosphorylates I kappa B alpha. LPS stimulation transiently enhanced the I kappa B alpha-bound kinase activity in THP-1 cells. Mutational analyses of I kappa B alpha and competition experiments with the synthetic peptides identified major phosphorylation sites by the bound kinase as Ser and Thr residues in the C-terminal acidic domain of I kappa B alpha. Moreover, we show that the peptide, corresponding to the C-terminal acidic domain of I kappa B alpha, blocked the LPS-induced NF-kappa B activation as well as inducible phosphorylation of endogenous I kappa B alpha in a cell-free system using THP-1 cells. These results suggested that the bound kinase is involved in the signaling pathway of LPS by inducing the phosphorylation of the C-terminal region of I kappa B alpha and subsequent dissociation of the NF-kappa B.I kappa B alpha complex.

Amino Acid Sequence↗

Tumor necrosis factor (TNF) is a physiologic regulator of hematopoietic progenitor cells: increase of early hematopoietic progenitor cells in TNF receptor p55-deficient mice in vivo and potent inhibition of progenitor cell proliferation by TNF alpha in vitro.

Murine bone marrow cells with lineage phenotypes (Lin)-Sca-1+c-kit+ and Lin-Sca-1-c-kit+ cells represent primitive hematopoietic stem cells (HSCs) and committed hematopoietic progenitor cells, respectively. The number of Lin-Sca-1+c-kit+ HSCs in bone marrow was significantly increased in tumor necrosis factor (TNF) receptor p55-deficient (TNF-R55-1-) mice compared with the TNF-R55+/+ wild-type mice without a marked change in bone marrow cellularity. In both the methylcellulose culture and a single-cell proliferation assay, mouse TNF alpha (mTNF alpha) inhibited in vitro the proliferation of wild-type mouse-derived Lin-Sca-1+c-kit+ cells in response to a combination of multiple growth factors. The same is true for that of Lin-Sca-1+c-kit+ cells stimulated with granulocyte colony-stimulating factor (G-CSF) plus stem cell factor (SCF). Moreover, mTNF alpha significantly arrested the entry into S-phase from G0/G1 phase of Lin-Sca-1+c-kit+ cells stimulated with multiple growth factors and Lin-Sca-1-c-kit+ cells stimulated with G-CSF plus SCF. In contrast, mTNF alpha failed to affect the growth and cell cycle progression of Lin-Sca-1+c-kit+ cells and Lin-Sca-1-c-kit+ cells that were obtained from TNF-R55-deficient mice. These data suggest that TNF may be an important physiologic regulator of hematopoiesis and that TNF-R55 may be essentially involved in TNF-mediated inhibition of the growth of both primitive stem and more committed progenitor cells.

Animals↗

Regulatory mechanisms for production of IFN-gamma and TNF by antitumor T cells or macrophages in the tumor-bearing state.

Spleen cells from BALB/c mice bearing a syngeneic tumor (CSA1 M) 2 to 3 wk after inoculation with CSA1 M cells produced IL-2, IFN-gamma, and TNF upon in vitro cultures. This was previously demonstrated to be a result of collaboration between tumor-primed CD4+ T cells and APCs binding CSA1 M tumor Ags in vivo. The IL-2- and IFN-gamma-producing capacities decreased with the progress of tumor-bearing stages. This was parallel to the levels of IL-2 and IFN-gamma mRNAs expressed by cultured spleen cells. In contrast, comparable levels of TNF mRNA were expressed by all groups of cultured cells. However, large amounts of TNF were secreted by the cells from early but not from late tumor-bearing mice. TNF was produced mainly by the non-T cell fraction upon stimulation with CD4+ T cell-derived IFN-gamma. Therefore, the reduced TNF production by whole spleen cells from late tumor-bearing mice was restored by addition of rIFN-gamma to their cultures. Reciprocally to the progressive decrease in the production of IFN-gamma/TNF, the capacities of tumor-bearing mice to produce TGF-beta and IL-6 increased along with tumor growth. TGF-beta suppressed production of IL-2, IFN-gamma, and TNF, but not of IL-6. Moreover, IFN-gamma/TNF production was negatively regulated by IL-6. Taken together with the fact that the growth of CSA1 M cells is completely inhibited by the combination of TNF and IFN-gamma, these results demonstrate that the tumor-bearing state induces an abnormal cytokine network under which the production of antitumor cytokines is negatively regulated.

Animals↗

Establishment of lipopolysaccharide-dependent nuclear factor kappa B activation in a cell-free system.

Nuclear factor kappa B (NF-kappa B), consisting of p50 and p65, is bound to a cytoplasmic retention protein, I kappa B, in a resting state, and the stimulation of cells with a variety of inflammatory stimuli induces the dissociation of NF-kappa B from I kappa B and the nuclear translocation of NF-kappa B, thereby activating several genes involved in inflammatory responses, such as interleukin (IL)-6, IL-8, and tumor necrosis factor alpha. In order to elucidate the precise mechanism of NF-kappa B activation, we have established lipopolysaccharide (LPS)-dependent NF-kappa B activation in a cell-free system using plasma membrane-enriched, cytosol, and nuclear fractions extracted from a human monocytic cell line, THP-1, by disruption with sonication followed by a differential centrifugation. The combination of plasma membrane-enriched fraction and cytosol was sufficient to activate NF-kappa B in a LPS/CD14-dependent manner only in the presence of ATP as judged by the binding of NF-kappa B to the IL-8 gene kappa B site on an electrophoretic mobility shift assay. LPS-dependent NF-kappa B activation was inhibited by protein kinase inhibitors, such as staurosporine, herbimycin A, tyrphostin, and genistein, but not mitogen-activated protein kinase substrate, cGMP-dependent protein kinase, cAMP-dependent protein kinase, protein kinase C, and calmodulin-dependent protein kinase II inhibitory peptides, suggesting that staurosporine-sensitive kinase(s) as well as tyrosine kinase(s) are involved in LPS-mediated NF-kappa B activation. In addition, LPS induced the phosphorylation of I kappa B-alpha, starting at 5 min after the stimulation in a cell-free system. Moreover, the phosphorylation was inhibited by herbimycin A and tyrphostin, but not staurosporine, suggesting that these protein kinase inhibitors act at distinct steps of signal transmission. Establishment of ligand-dependent activation of NF-kappa B in a cell-free system will facilitate identification of protein kinase(s) and its substrate(s) involved in LPS-mediated NF-kappa B activation.

Amino Acid Sequence↗

Molecular analysis of the cytokine network involved in cachexia in colon 26 adenocarcinoma-bearing mice.

Two clones, one cachexigenic (clone 20) and the other noncachexigenic (clone 5), from a murine colon adenocarcinoma, colon 26 cells, were used to analyze the involvement of immune reactions as well as the cytokine network in cachexia. Clone 20 induced cachexia in nude and SCID mice as well as in normal BALB/c mice, suggesting that lymphocytes played little, if any, role in the process. Both clones failed to express mRNA of interleukin (IL) 1 alpha, IL-1 beta, IL-6, and tumor necrosis factor alpha in vitro with or without the coculture of NIH3T3 cells or spleen cells. However, IL-6 mRNA was selectively detected at the tumor site of clone 20 but not at that of clone 5-bearing mice. In contrast, tumor necrosis factor alpha mRNA was detected at tumor sites and in spleens of only clone 5-bearing mice, suggesting a potential role of IL-6, but not tumor necrosis factor alpha, in inducing cachexia. Anti-IL-6 antibody partially reversed the weight loss induced by clone 20, whereas the continuous infusion of IL-6 failed to cause weight loss, despite being associated with an elevation of a serum acute phase protein. These results suggest that IL-6 is necessary but not sufficient for the induction of cachexia. Both clones expressed IL-6 mRNA in the presence of IL-1 in vitro, and mice bearing either clone expressed IL-1 beta mRNA at the tumor site. Moreover, IL-1 receptor antagonist (IL-1Ra) mRNA was detected at the tumor site of clone 5-bearing mice but not at that of clone 20-bearing mice, suggesting that IL-1Ra might block IL-1 activity to reduce IL-6 production in clone 5-bearing mice. However, the transfection of clone 20 with IL-1Ra cDNA failed to abolish its capacity to produce IL-6 and to cause cachexia. Collectively, additional factor(s) besides IL-1Ra and IL-1 beta may control IL-6 and some other cachexigenic factor production, thereby causing cachexia in this model.

Adenocarcinoma↗

Expression of both types of human interleukin-8 receptors on mature neutrophils, monocytes, and natural killer cells.

cDNA cloning revealed the presence of two related but distinct types of human interleukin-8 (IL-8) receptors, type I (type A) and type II (type B). By immunizing rabbits with glutathione-S-transferase fused with the NH2-terminal domain of each type of IL-8 receptor, we prepared polyclonal antibodies that specifically recognized the NH2-terminal domain of each type of IL-8 receptor. Immunofluorescence analysis of human peripheral blood leukocytes demonstrated that mature granulocytes except eosinophils express both types of IL-8 receptors. A majority of monocytes and CD16+ natural killer (NK) cells in peripheral blood were stained with both antibodies, whereas CD3+ T or CD20+ B lymphocytes in peripheral blood or CD34+ cells in cord blood were not stained with either antibody. These results suggest that both types of human IL-8 receptors were coordinately and selectively expressed in mature granulocytes, monocytes, and CD16+ NK cells.

Amino Acid Sequence↗

Differential effects of anti-inflammatory cytokines (IL-4, IL-10 and IL-13) on tumoricidal and chemotactic properties of human monocytes induced by monocyte chemotactic and activating factor.

The effect of recombinant human IL-4, IL-10, and IL-13 on the chemotaxis and antitumor activity of human blood monocytes induced by monocyte chemotactic and activating factor (MCAF) was examined. MCAF alone did not induce monocyte-mediated cytotoxicity against human melanoma (A375-M) cells whereas it significantly enhanced the cytotoxicity by norMDP-stimulated monocytes. MCAF, unlike IFN-gamma, had no priming effect on monocyte activation by norMDP. MCAF acted with norMDP or LPS to enhance the production of both IL-1 beta and TNF-alpha. Enhanced cytotoxicity of monocytes stimulated with MCAF plus norMDP was reduced by IL-1 receptor antagonist and anti-TNF-alpha antibody. IL-4, IL-10, and IL-13 suppressed the generation of antitumor activity and cytokine production (IL-1 beta and TNF-alpha) of monocytes stimulated with MCAF plus norMDP or LPS. Chemotaxis of monocytes induced by MCAF was not affected by norMDP or any of the anti-inflammatory cytokines (IL-4, IL-10, and IL-13). Moreover, the pretreatment of monocytes with anti-inflammatory cytokines did not suppress monocyte-chemotaxis. These findings suggest that in vivo recruitment and anti-tumor expression of blood monocytes induced by MCAF may be differently regulated by anti-inflammatory cytokines in vivo.

Acetylmuramyl-Alanyl-Isoglutamine↗

Preparation of specific antibodies against murine IL-1ra and the establishment of IL-1ra as an endogenous regulator of bacteria-induced fulminant hepatitis in mice.

Blocking monoclonal antibodies (mAbs) specific to mouse interleukin-1 receptor antagonist (IL-1ra) were prepared by immunizing Armenian hamsters with recombinant mouse IL-1ra. A sensitive and specific ELISA against mouse IL-1ra was also established. In Propionibacterium acnes-induced liver injury, P. acnes induced transient increase of serum tumor necrosis factor-alpha levels but not those of IL-1ra, IL-1, and IL-6. However, subsequent lipopolysaccharide (LPS) challenge induced the increase of serum levels of all these cytokines and the peak serum IL-1ra level was more than 20 times as high as serum IL-1 levels. Immunohistochemical analysis demonstrated that IL-1ra was predominantly produced by hepatocytes during the course of the priming phase by P. acnes and eliciting phase by LPS challenge. Furthermore, the administration of a mAb to mouse IL-1ra exacerbates the liver injury induced by P. acnes and sublethal dose of LPS, suggesting a protective role of endogenous IL-1ra in this liver injury model.

Animals↗

Human MCAF gene transfer enhances the metastatic capacity of a mouse cachectic adenocarcinoma cell line in vivo.

PURPOSE: To evaluate the effect of monocyte chemotactic and activating factor (MCAF/MCP-1/JE) on tumor progression and metastasis. METHODS: Cachexia-inducing adenocarcinoma cells (cell line colon 26, clone 20) were transfected with either a control plasmid or MCAF expression vector. Spontaneous lung metastases were determined in mouse. RESULTS: The production of MCAF reached 0.4 ng/ml in vitro when transfectant cells were cultured at a cell density of 5 x 10(4) cells/ml for 3 days. Transfection of MCAF expression vector did not affect the growth rate in vitro. Also, after MCAF-transfection, the size of tumors after intra-footpad inoculation was similar to that of the parental cells. When the primary tumors were resected on the 10th day after inoculation, the incidence of spontaneous lung metastasis was less than 20% in both cells. The number of endothelial cells in the primary tumor rapidly increased from the 10th to the 14th day after inoculation, as revealed by immunohistochemical staining. In accordance with enhanced angiogenesis, the incidence rates of spontaneous metastasis increased when the primary tumors were resected on the 14th day after inoculation. Moreover, the spontaneous lung metastases were augmented in the animals injected with MCAF-transfectants compared to those injected with parental cells with a concomitant increase of angiogenesis. CONCLUSIONS: These results suggest that MCAF may augment the metastastic potential by modulating tumor associated angiogenesis.

Adenocarcinoma↗

Chemokine gene transfection into tumour cells reduced tumorigenicity in nude mice in association with neutrophilic infiltration.

To study the effect of localised secretion of chemokines on tumour growth, the genes for human (hu) interleukin 8 (IL-8), hu-MCP-1 (MCAF), hu-MIP-1 alpha (LD78), murine (mu)-MCP-1 (JE), mu-MIP-1 alpha or mu-MIP-2 were introduced, via mammalian expression vectors, into Chinese hamster ovary (CHO) cells, and the ability of transfected cells to form tumours in vivo was evaluated. The production of hu-IL-8, hu-MIP-1 alpha or mu-MIP-1 alpha by transfected clones did not influence the growth rate in vitro, but drastically suppressed tumour growth when injected subcutaneously (s.c.) into nude mice. However, clones transfected with hu-MCP-1, mu-MCP-1 or mu-MIP-2 did not show any significant difference in growth rate in vivo compared with clones transfected with vector alone. Histological examination of the site of injection of CHO clones transfected with hu-IL-8, hu-MIP-1 alpha or mu-MIP-1 alpha showed predominantly neutrophilic infiltration. These results indicate that chemokines have potent anti-tumour activity when released, even at low doses, at the tumour site, which may be mediated by recruitment and targeting of neutrophilic granulocytes to chemokine-releasing cells. Our studies highlight the potential usefulness of localised chemokine secretion in inducing potent host anti-tumour defensive responses.

Amino Acid Sequence↗

Prevention of endotoxin shock by an antibody against leukocyte integrin beta 2 through inhibiting production and action of TNF.

Septic shock remains a serious disorder associated with high mortality. Accumulating evidence indicates that TNF is a major and essential mediator of endotoxin shock. We report here that administration of an antibody against CD18 dramatically reduced endotoxin-induced shock in rabbits as revealed by prevention of severe hypotension, metabolic acidosis and a pathological change suggestive of disseminated intravascular coagulation with concomitant inhibition of elevation of plasma TNF activity. The anti-CD18 antibody also inhibited the hypotension induced by administering recombinant TNF. Furthermore, an antibody against a ligand for CD18 complexes, intercellular adhesion molecule-1, also prevented TNF-induced shock as well as endotoxin shock in rabbits. These observations suggest that adhesion of leukocytes to endothelium may be of primary importance in the action of TNF as well as in the production of TNF in vivo and that the antibody against adhesion molecules could be of therapeutic benefit in life-threatening septic shock in humans.

Acute-Phase Reaction↗

Prevention of endotoxin-induced acute lethality in Propionibacterium acnes-primed rabbits by an antibody to leukocyte integrin beta 2 with concomitant reduction of cytokine production.

Acute lethality was induced in rabbits by the sequential injection of Propionibacterium acnes and lipopolysaccharide (LPS). P. acnes induced the infiltration of inflammatory cells into the liver lobules during the early phase, and LPS in the late phase caused death in association with pathological changes mimicking hepatocellular necrosis or degeneration around infiltrated mononuclear cells and fibrin deposition in the liver, lung, and kidney, suggestive of a systemic Schwartzman-like reaction. These pathological changes were accompanied by the elevation of plasma tumor necrosis factor (TNF) and interleukin-8 (IL-8) levels. A neutralizing antibody to a leukocyte adhesion molecule, integrin beta 2 (CD18), administered at the time of LPS challenge, prevented reduced the elevation of plasma TNF and IL-8 levels. An anti-TNF alpha antibody but not an anti-IL-8 mediator in this model. These results indicate that CD18 is critically involved in vivo in activating leukocytes to produce cytokines in response to LPS.

Animals↗

Specific increase in interleukin-8 concentrations in dialysis fluid of patients with peritonitis receiving continuous ambulatory peritoneal dialysis.

AIMS: To evaluate the influence of interleukin-8 (IL-8) and other inflammatory cytokines (IL-6, IL-1 beta and tumour necrosis factor alpha (TNF alpha)) on the occurrence of peritonitis in patients receiving continuous ambulatory peritoneal dialysis (CAPD). METHODS: The study population comprised 12 patients with peritonitis, 33 without peritonitis, all undergoing CAPD, and five patients undergoing peritoneal catheter implantation. Cytokine concentrations in dialysis fluid were determined by immunoassay and their values compared. RESULTS: Concentrations of both IL-8 (median 147 pg/ml, range 20-2273 pg/ml; n = 12) and IL-6 (median 1120 pg/ml, range 96-10,600 pg/ml) were substantially elevated, while the IL-1 beta concentration was lower and TNF alpha was not detectable in patients at diagnosis. The IL-6 concentration was also elevated in patients undergoing catheter implantation as well as in those with peritonitis. The IL-8 concentration, however, was elevated only upon infection. Intraperitoneal production of IL-8 was evident on determination of paired serum and dialysis fluid cytokine concentrations, and immunostaining of peritoneal cells with monoclonal anti-IL-8 antibody. CONCLUSIONS: These results suggest that determination of the IL-8 concentration in dialysis fluid maybe useful as a specific marker for following patients with peritonitis receiving CAPD.

Adult↗

Chemokines in bronchoalveolar lavage fluid in summer-type hypersensitivity pneumonitis.

Hypersensitivity pneumonitis (HP) is a granulomatous interstitial lung disease caused by the inhalation of a variety of antigens and is characterized by a dramatic accumulation of inflammatory cells, including neutrophils, lymphocytes and macrophages, in the lung. The mechanisms implicated in the inflammatory cell recruitment observed in hypersensitivity pneumonitis are unknown. We examined the concentrations of two important chemokines, interleukin-8 (IL-8) and monocyte chemoattractant protein-1/monocyte chemotactic and activating factor (MCP-1/MCAF), in the bronchoalveolar lavage fluid (BALF) of patients with summer-type hypersensitivity pneumonitis (n = 8), and compared them with those in patients with sarcoidosis (n = 13) and with controls (n = 8). In the BALF of summer-type hypersensitivity pneumonitis, the levels both of IL-8 and MCP-1 were significantly increased compared with levels measured in control subjects. On the other hand, compared to the control value, the MCP-1 level in the BALF of the sarcoidosis patients was significantly increased, but IL-8 was only slightly and nonsignificantly increased. Since IL-8 is a chemoattractant for neutrophils and T-lymphocytes, whereas MCP-1 acts mainly on monocytes/macrophages, our findings may indicate that these two chemokines participate in the cellular accumulation observed in hypersensitivity pneumonitis.

Alveolitis, Extrinsic Allergic↗

Establishment and characterization of a human malignant fibrous histiocytoma cell line.

Malignant fibrous histiocytoma is the most frequent soft tissue sarcoma. However, the pathogenesis still remains unclear, because there are very few human malignant fibrous histiocytoma cell lines available for precise cellular study. In this study, a human malignant fibrous histiocytoma cell line (MMF-1) was established from the pulmonary metastatic lesion of a 55-year-old man with malignant fibrous histiocytoma. Human cell line MMF-1 and its heterotransplanted tumor had almost the same characteristics as the original tumor morphologically and immunohistochemically. This cell line is expected to be a useful for studying the pathogenesis of malignant fibrous histiocytoma. The cloned cell lines (MMF-2 and MMF-3) also consisted of spindle-shaped, polygonal, and multinucleated giant cells, meaning that the fibroblast-like cells, histiocyte-like cells, and multinucleated giant cells seen in malignant fibrous histiocytoma were derived from a single tumor cell. Human cell line MMF-1 produced inflammatory cytokines, such as tumor necrosis factor-alpha, macrophage colony-stimulating factor, interleukin-8, and monocyte chemotactic and activating factor, that might be involved in the morphogenesis of malignant fibrous histiocytoma. Furthermore, the results of the analysis of human cell line MMF-1 suggested that malignant fibrous histiocytoma originated from a poorly differentiated fibroblast.

Cell Division↗