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K Kuida

Publications and source records attributed to K Kuida.

At least 37 records · Page 2Linked to original sources

Response to local inflammation of IL-1 beta-converting enzyme- deficient mice.

IL-1 beta-converting enzyme (ICE) cleaves pro-IL-1 beta to the mature, released form. Although other proteases can process pro-IL-1 beta, ICE-deficient (ICE -/-) mice do not release mature IL-1 beta in response to endotoxin. The purpose of our study was to investigate the response of ICE -/- mice in two models of local inflammation, turpentine-induced tissue damage and zymosan-induced peritonitis. No differences were observed in the development of the systemic acute phase response after turpentine administration between wild-type and ICE -/- mice, but this response was completely impaired in IL-1 beta -/- mice. Accordingly, the levels of mature IL-1 beta produced in response to turpentine did not differ between wild-type and ICE -/- mice. In contrast, following zymosan-induced peritonitis, the levels of mature IL-1 beta were significantly lower in ICE -/- mice. This was associated with a 50% decrease in cellular infiltrate in ICE -/- mice compared with that in wild-type controls. The reduced production of zymosan-induced mature IL-1 beta in ICE -/- mice was also observed from cultured peritoneal or spleen cells. Our results demonstrate that in turpentine-induced tissue necrosis, precursor IL-1 beta is processed by non-ICE proteases, but in complement-mediated inflammation, ICE participates in the processing of the IL-1 beta precursor.

Animals↗

Bcl-2 lies downstream of parathyroid hormone-related peptide in a signaling pathway that regulates chondrocyte maturation during skeletal development.

Parathyroid hormone-related peptide (PTHrP) appears to play a major role in skeletal development. Targeted disruption of the PTHrP gene in mice causes skeletal dysplasia with accelerated chondrocyte maturation (Amizuka, N., H. Warshawsky, J.E. Henderson, D. Goltzman, and A.C. Karaplis. 1994. J. Cell Biol. 126:1611-1623; Karaplis, A.C., A. Luz, J. Glowacki, R.T. Bronson, V.L.J. Tybulewicz, H.M. Kronenberg, and R.C. Mulligan. 1994. Genes Dev. 8: 277-289). A constitutively active mutant PTH/PTHrP receptor has been found in Jansen-type human metaphyseal chondrodysplasia, a disease characterized by delayed skeletal maturation (Schipani, E., K. Kruse, and H. Jüppner. 1995. Science (Wash. DC). 268:98-100). The molecular mechanisms by which PTHrP affects this developmental program remain, however, poorly understood. We report here that PTHrP increases the expression of Bcl-2, a protein that controls programmed cell death in several cell types, in growth plate chondrocytes both in vitro and in vivo, leading to delays in their maturation towards hypertrophy and apoptotic cell death. Consequently, overexpression of PTHrP under the control of the collagen II promoter in transgenic mice resulted in marked delays in skeletal development. As anticipated from these results, deletion of the gene encoding Bcl-2 leads to accelerated maturation of chondrocytes and shortening of long bones. Thus, Bcl-2 lies downstream of PTHrP in a pathway that controls chondrocyte maturation and skeletal development.

Animals↗

Activation of interferon-gamma inducing factor mediated by interleukin-1beta converting enzyme.

The interleukin-1beta (IL-1beta) converting enzyme (ICE) processes the inactive IL-1beta precursor to the proinflammatory cytokine. ICE was also shown to cleave the precursor of interferon-gamma inducing factor (IGIF) at the authentic processing site with high efficiency, thereby activating IGIF and facilitating its export. Lipopolysaccharide-activated ICE-deficient (ICE-/-) Kupffer cells synthesized the IGIF precursor but failed to process it into the active form. Interferon-gamma and IGIF were diminished in the sera of ICE-/- mice exposed to Propionibacterium acnes and lipopolysaccharide. The lack of multiple proinflammatory cytokines in ICE-/- mice may account for their protection from septic shock.

Animals↗

Interleukin-1 beta converting enzyme (ICE) is preferentially expressed in neuroblastomas with favourable prognosis.

To determine whether interleukin-1 beta converting enzyme (ICE) plays a role in the programmed cell death of neuroblastoma, we studied ICE expression in primary tumours. In patients in stages I, II and IVS, ICE mRNA was detected in 22 of 32 (69%) tumours, while only 5 of 26 (19%) tumours expressed ICE in stages III and IV (P < 0.001). ICE mRNA was expressed in 27 of 47 (57%) tumours without MYCN amplification, but it was not detected in any tumours with MYCN amplification (P < 0.01). Immunohistochemically, the cytoplasm was stained in all 15 neuroblastomas examined. The nuclei were stained in 12 neuroblastomas without MYCN amplification, whereas only 1 of 3 tumours with MYCN amplification had positive staining in the nuclei. In ganglioneuromas, high levels of ICE mRNA were expressed, but immunostaining showed that the protease expression was confined to the cytoplasm. These observations suggest that ICE may be associated with the spontaneous regression often seen in favourable neuroblastomas and that localisation of ICE protease in the cell may be important for the cell death pathway. Double staining for ICE and TUNEL showed that they were co-localised in some nuclei, but the distribution of ICE protease expression was not necessarily the same as that of DNA fragmentation, suggesting that the protease expression probably preceded DNA fragmentation during the apoptotic process. ICE may play an important role in regulating the apoptotic process of neuroblastoma.

Blotting, Northern↗

The roles of preB cell receptor in early B cell development and its signal transduction.

The preB cell receptor is expressed for a short period after mu heavy chain is produced, that is, at the large preB cell stage in B cell development. The severe impairment of B cell differentiation observed in mice deficient for the preB cell receptor clearly demonstrated the importance of the preB cell receptor in B cell development. Analyses of bone marrow precursor B cells in normal and B cell-deficient mutant mice indicated the preB cell receptor transduced signals to drive cell cycle and to induce allelic exclusion. The proliferation of the preB cell receptor-expressing cells leads to the selective expansion of cells which have succeeded in the productive rearrangement of mu heavy chain gene. This process builds up a preB cell pool large enough to generate sufficient numbers of mature B cells. The preB cell receptor appears to induce allelic exclusion by shutting off the expression of recombinase activation gene (RAG). In order to analyse the signal transduction pathway downstream of the preB cell receptor, we have developed a new system in which cross-linking of Ig beta expressed on bone marrow proB cells mimics the signalling through the preB cell receptor to induce differentiation from proB to small preB cells.

Alleles↗

Activation of the STAT signaling pathway can cause expression of caspase 1 and apoptosis.

Protein tyrosine kinases activate the STAT (signal transducer and activator of transcription) signaling pathway, which can play essential roles in cell differentiation, cell cycle control, and development. However, the potential role of the STAT signaling pathway in the induction of apoptosis remains unexplored. Here we show that gamma interferon (IFN-gamma) activated STAT1 and induced apoptosis in both A431 and HeLa cells, whereas epidermal growth factor (EGF) activated STAT proteins and induced apoptosis in A431 but not in HeLa cells. EGF receptor autophosphorylation and mitogen-activated protein kinase activation in response to EGF were similar in both cell lines. The breast cancer cell line MDA-MB-468 exhibited a similar response to A431 cells, i.e., STAT activation and apoptosis correlatively resulted from EGF or IFN-gamma treatment. In addition, in a mutant A431 cell line in which STAT activation was abolished, no apoptosis was induced by either EGF or IFN-gamma. We further demonstrated that both EGF and IFN-gamma induced caspase 1 (interleukin-1beta converting enzyme [ICE]) gene expression in a STAT-dependent manner. IFN-gamma was unable to induce ICE gene expression and apoptosis in either JAK1-deficient HeLa cells (E2A4) or STAT1-deficient cells (U3A). However, ICE gene expression and apoptosis were induced by IFN-gamma in U3A cells into which STAT1 had been reintroduced. Moreover, both EGF-induced apoptosis and IFN-gamma-induced apoptosis were effectively blocked by Z-Val-Ala-Asp-fluoromethylketone (ZVAD) in all the cells tested, and studies from ICE-deficient cells indicated that ICE gene expression was necessary for IFN-gamma-induced apoptosis. We conclude that activation of the STAT signaling pathway can induce apoptosis through the induction of ICE gene expression.

Apoptosis↗

Decreased apoptosis in the brain and premature lethality in CPP32-deficient mice.

Programmed cell death (apoptosis) is a prominent feature of the development of the immune and nervous systems. The identification of the Caenorhabditis elegans cell death gene, ced-3, as a prototype of the interleukin-1beta converting enzyme (ICE) protease family has led to extensive evidence implicating these enzymes in apoptosis. Among the ten or more members of the ICE protease family, CPP32/yama/apopain exhibits the highest similarity to CED-3 in both sequence homology and substrate specificity. To analyse its function in vivo, we generated CPP32-deficient mice by homologous recombination. These mice, born at a frequency lower than expected by mendelian genetics, were smaller than their littermates and died at 1-3 weeks of age. Although their thymocytes retained normal susceptibility to various apoptotic stimuli, brain development in CPP32-deficient mice was profoundly affected, and discernible by embryonic day 12, resulting in a variety of hyperplasias and disorganized cell deployment. These supernumerary cells were postmitotic and terminally differentiated by the postnatal stage. Pyknotic clusters at sites of major morphogenetic change during normal brain development were not observed in the mutant embryos, indicating decreased apoptosis in the absence of CPP32. Thus CPP32 is shown to play a critical role during morphogenetic cell death in the mammalian brain.

Animals↗

Altered cytokine export and apoptosis in mice deficient in interleukin-1 beta converting enzyme.

The interleukin-1 beta (IL-1 beta) converting enzyme (ICE) processes the inactive IL-1 beta precursor to the proinflammatory cytokine. Adherent monocytes from mice harboring a disrupted ICE gene (ICE-/-) did not export IL-1 beta or interleukin-1 alpha (IL-1 alpha) after stimulation with lipopolysaccharide. Export of tumor necrosis factor-alpha and interleukin-6 (IL-6) from these cells was also diminished. Thymocytes from ICE-/- mice were sensitive to apoptosis induced by dexamethasone or ionizing radiation, but were resistant to apoptosis induced by Fas antibody. Despite this defect in apoptosis, ICE-/- mice proceed normally through development.

Amino Acid Sequence↗

Dysregulated expression of the IL-2 receptor beta-chain abrogates development of NK cells and Thy-1+ dendritic epidermal cells in transgenic mice.

The IL-2 receptor beta-chain (IL-2R beta), a specificity-determining subunit in the IL-2R complex with a restricted tissue distribution pattern, is essential for signal transduction. Our previous studies demonstrate that the continuous treatment of mice with anti-IL-2R beta resulted in the complete disappearance of NK cells and Thy-1+ dendritic epidermal cells (Thy-1+ dEC), suggesting that signals through IL-2R beta are critically involved in development of these lymphocyte subsets. However, these lymphocyte subsets are reported to be apparently unaffected in the IL-2-deficient mice. To further examine the biological roles of the IL-2R beta, transgenic mice carrying the IL-2R beta transgene were generated. In these mice, high levels of the cell surface expression of the IL-2R beta were observed in essentially all hematopoietic lineage cells, and CD4+ T cells as well as CD8+ T cells showed vigorous cell proliferation upon IL-2 stimulation. Surprisingly, NK cells marked with a high expression of NK1.1 in the spleen and Thy-1+ dEC in the skin were completely absent in transgenic mice. However, the development of other lymphocyte subsets including conventional alpha beta TCR+ cells, gamma delta TCR+ cells and B cells remained apparently intact. From these observations together with previous data on IL-2-deficient mice, we speculate that factors, other than IL-2 that utilizes the IL-2R beta as its functional receptor subunit, may have a vital role in the development of NK cells and Thy-1+ dEC. Implications for possible in vivo functions of over-expressed IL-2R beta are discussed.

Animals↗

Targeted disruption of Bcl-2 alpha beta in mice: occurrence of gray hair, polycystic kidney disease, and lymphocytopenia.

Mice carrying ablated coding regions of the bcl-2 alpha and bcl-2 beta transcripts have been made. bcl-2-/- mutants are smaller but viable, although about half of them die by 6 weeks of age. As shown earlier with somatic bcl-2 gene-targeted mice, the number of lymphocytes markedly decreased within few weeks after birth while other hematopoietic lineages remained unaffected. Among lymphocytes, CD8+ T cells disappeared most quickly followed by CD4+ T cells, whereas B cells were least affected. bcl-2-/- lymphocytes, however, could respond normally to various stimuli including anti-CD3, Con A, phorbol 12-myristate 13-acetate plus ionomycin, interleukin 2, lipopolysaccharide, and anti-IgM antibody. Abnormalities among nonlymphoid organs include smaller auricles, hair color turning gray at 4-5 weeks of age, and polycystic kidney disease-like change of renal tubules. These results suggest that Bcl-2 may be involved during morphogenesis where inductive interactions between epithelium and mesenchyme are important such as in the kidneys, hair follicles, and perichondrium of auricles. Surprisingly, the nervous system, intestines, and skin appear normal despite the fact that these organs show high levels of endogenous Bcl-2 expression in normal mice.

Animals↗

Requirement for CD8 beta chain in positive selection of CD8-lineage T cells.

CD8 is either an alpha alpha homodimer or an alpha beta heterodimer, although most peripheral CD8-lineage T cells express only the CD8 alpha beta heterodimer. The physiological function of CD8 beta was elucidated with mice that were chimeric for the homozygous disruption of the CD8 beta gene. The CD8 beta-1- T cells developed normally to CD4+CD8+ stage, but did not efficiently differentiate further, which resulted in few peripheral CD8+ T cells. The number of peripheral CD8+ T cells was restored by transfer of an exogenous CD8 beta gene into CD8 beta-deficient T cells. Thus, CD8 beta is necessary for the maturation of CD8+ T cells.

Animals↗

Disappearance of the lymphoid system in Bcl-2 homozygous mutant chimeric mice.

The bcl-2 proto-oncogene can prevent the death of many cell types. Mice were generated that were chimeric for the homozygous inactivation of bcl-2. Lymphocytes without Bcl-2 differentiated into phenotypically mature cells. However, in vitro, the mature T cells that lacked Bcl-2 had shorter life-spans and increased sensitivity to glucocorticoids and gamma-irradiation. In contrast, stimulation of CD3 inhibited the death of these cells. T and B cells with no Bcl-2 disappeared from the bone marrow, thymus, and periphery by 4 weeks of age. Thus, Bcl-2 was dispensable for lymphocyte maturation, but was required for a stable immune system after birth.

Animals↗

Selective long-term elimination of natural killer cells in vivo by an anti-interleukin 2 receptor beta chain monoclonal antibody in mice.

The interleukin 2 receptor beta chain (IL-2R beta) is preferentially expressed in natural killer (NK) cells, but is not detected in a majority of resting T and B cells. We recently established a novel monoclonal antibody (mAb) to murine IL-2R beta and examined in vivo the effect of the mAb in mice. We found that intraperitoneal injection of the anti-IL-2R beta mAb into adult mice resulted in a selective in vivo elimination of splenic NK function in various mouse strains. The reduction of NK cell function is associated with complete disappearance of NK1.1+ cells in C57BL/6 mice. Other lymphocyte subsets in the thymus and spleen were uncompromised. T cell function was not affected by the mAb treatment as judged by allogeneic cytotoxic T cell induction. The single injection of anti-IL-2R beta mAb caused a long-term elimination of splenic NK cells, lasting for at least 5 wk. We also found that NK and/or NK precursor cells become susceptible to the mAb treatment only after birth, suggesting that functional maturation of NK cells in terms of IL-2R beta expression is a later event in the course of NK cell development. The use of the anti-IL-2R beta mAb will be useful in defining the physiological role of NK cells in host defense as well as dissecting their developmental pathway in vivo.

Animals↗

Molecular mechanisms underlying lymphocyte recirculation. III. Characterization of the LECAM-1 (L-selectin)-dependent adhesion pathway in rats.

LECAM-1 (L-selectin) is thought to play an important role in the binding of lymphocytes to high endothelial venules (HEV) of peripheral lymph nodes (LN), which is an essential process in lymphocyte recirculation. Previously we cloned the rat LECAM-1 cDNA. In this study, by using this probe we have sought to characterize a LECAM-1-dependent adhesion pathway in the rat. We have constructed a cDNA for rat LECAM-1-IgG chimera (rLEC-IgG), expressed it, purified the secreted recombinant chimera molecules, and produced mAb reactive with the rat homologue of LECAM-1 by using the chimera molecules. The use of rLEC-IgG revealed that ligands for LECAM-1 are selectively accumulated in high endothelial (HE) cells in LN, the white matter, neurons, cerebellar Purkinje cells, and choroid plexus of the central nervous system and also distal tubules and capillary blood vessels of the kidney. Binding of lymphocytes to LN HEV on frozen sections was blocked by either rLEC-IgG or the anti-rat LECAM-1 mAb. An HEV-derived cell line, Ax, specifically bound to rLEC-IgG fixed on plastic plate. Consistent with the presence of a C-type lectin domain in the ligand-binding region of LECAM-1, the binding was Ca2+ dependent and inhibitable by either the mannose-6-phosphate-rich polysaccharide polyphosphomannan ester or the anti-rat LECAM-1 mAb. These results indicate that the specific ligand for rat LECAM-1 is expressed on the Ax cells. rLEC-IgG precipitated 55-, 65-, 120-, 190-, and > 250-kDa sulfated glycoproteins from LN lysates and 190-, > 250-, and > 500-kDa proteins from Ax cell lysate. The precipitation was Ca2+ dependent and LECAM-1 specific. These results suggest that a carbohydrate structure on HE cells recognized by LECAM-1 is borne possibly on a limited number of cell surface-sulfated glycoproteins. The ligands were also found to be secreted in LN culture supernatants. rLEC-IgG and Ax cells should prove valuable for studying further the role of LECAM-1 in dynamic interactions between lymphocytes and HE cells.

Animals↗

The role of the interleukin-2 (IL-2)/IL-2 receptor pathway in MRL/lpr lymphadenopathy: the expanded CD4-8- T cell subset completely lacks functional IL-2 receptors.

Autoimmune MRL/MP-lpr/lpr (MRL/lpr) mice spontaneously develop a systemic lupus erythematosus-like disease accompanied by a profound lymphadenopathy that consists of CD4-8-B220+ alpha beta T cells. By the use of cross-linking experiments with radiolabeled interleukin-2 (IL-2), these abnormal T cells have been reported to constitutively express the IL-2 receptor beta chain (IL-2R beta), a signal transducing component of IL-2R, in the absence of the alpha chain (IL-2R alpha). To critically reevaluate the role of the IL-2/IL-2R pathway in the pathogenesis of lymphadenopathy we examined expression of the IL-2R alpha and IL-2R beta in MRL/lpr mice by 125I-IL-2 binding analysis and also by flow cytometric analysis using monoclonal antibodies against each component of the receptor. We found that, contrary to the previous report, the CD4-8-B220+ alpha beta T cells in lymph node (LN) of MRL/lpr mice were negative for both IL-2R alpha and IL-2R beta expression. The lpr liver CD4-8-B220+ alpha beta T cells that had been implicated in the genesis of these abnormal LN T cells were also negative for IL-2R beta expression. Therefore, our results indicate that the IL-2/IL-2R system plays little role, if any, in the expansion of abnormal CD4-8-B220+ alpha beta T cells in MRL/lpr mice.

Animals↗