Publications by authors named "Yoichiro Iwakura"

The traditional use of Cordyceps militaris, an entomopathogenic fungus, in East Asian medicine has been well documented. Our previous study revealed that the fruiting body powder of C. militaris, referred to as Ryukyu-kaso, contains 1,3-β-glucan and stimulates bone marrow-derived dendritic cells via a dectin-1-dependent pathway.

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  • Memory-phenotype (MP) CD4 T lymphocytes develop from naïve T cells and can differentiate into various T cell subsets to manage inflammation, especially in low-immune settings.
  • The study highlights that MP lymphocytes are not only made up of T helper 1 (T1) and T helper 17 (T17) cells but also contain a "undifferentiated" subpopulation that has the potential to develop into these functional subsets.
  • The undifferentiated MP lymphocytes possess the ability to proliferate rapidly and can differentiate into T1, T17, and regulatory T cells, which contributes to inflammation, although their response is regulated by existing T cells.
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  • Interleukin-1 is a key pro-inflammatory cytokine linked to the development of inflammatory diseases, where its absence in knockout mice leads to conditions like aortitis, arthritis, and dermatitis.
  • Research shows that transferring T cells from these IL-1Ra KO mice into nude mice causes similar inflammatory diseases, raising questions about which specific T cell subsets are involved.
  • The study found increased levels of a particular CD4+ T cell subset that produces granulocyte macrophage colony-stimulating factor (GM-CSF) in IL-1Ra KO mice, suggesting these cells play a significant role in the enhanced inflammation observed in these models.
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Sensory disturbances and central nervous system symptoms are important in patients with Minamata disease. In the peripheral nervous system of these patients, motor nerves are not strongly injured, whereas sensory nerves are predominantly affected. In this study, we investigated the mechanisms underlying the sensory-predominant impairment of the peripheral nervous system caused by methylmercury.

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There are comorbidities and complications in atopic dermatitis and psoriasis that often occur after the appearance of skin inflammation. Statistically, data show that patients with psoriasis and atopic dermatitis have a shorter life expectancy than patients without psoriatic dermatitis, due to the occurrence of arteriosclerosis, myocardial infarction, and cerebral infarction. Many types of skin inflammation are treated with various antibody preparations, and marked improvement in patients' quality of life can be achieved.

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Cordyceps militaris, an entomopathogenic fungus, has been traditionally used in East Asian medicine. Recent research indicates that the fruit bodies of C. militaris are rich in bioactive compounds, such as polysaccharides and nucleosides, which may offer health benefits.

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  • Acute immune responses can be deadly due to excess production of cytokines and other harmful substances, creating complex and unpredictable issues in the body.
  • Research shows that certain triggers, like toll-like receptor (TLR) ligands and α-adrenergic receptor agonists, can lead to lethal damage in mice by increasing levels of platelet-activating factor (PAF).
  • Knocking out specific genes related to immune receptors and enzymes can prevent this damage, highlighting a significant connection between the nervous and immune systems in regulating PAF levels.
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is a yeast-type fungus that causes fatal meningoencephalitis in immunocompromised patients and evades phagocytic cell elimination through an escape mechanism. Memory T (Tm) cells play a central role in preventing the reactivation of this fungal pathogen. Among these cells, tissue-resident memory T (T) cells quickly respond to locally invaded pathogens.

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Osteosarcoma is rare but is the most common bone tumor. Diagnostic tools such as magnetic resonance imaging development of chemotherapeutic agents have increased the survival rate in osteosarcoma patients, although 5-year survival has plateaued at 70%. Thus, development of new treatment approaches is needed.

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Pancreatic islet inflammation plays a crucial role in the etiology of type 2 diabetes (T2D). Macrophages residing in pancreatic islets have emerged as key players in islet inflammation. Macrophages express a plethora of innate immune receptors that bind to environmental and metabolic cues and integrate these signals to trigger an inflammatory response that contributes to the development of islet inflammation.

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Acrylamide is an environmental electrophile that has been produced in large amounts for many years. There is concern about the adverse health effects of acrylamide exposure due to its widespread industrial use and also presence in commonly consumed foods and others. IL-1β is a key cytokine that protects the brain from inflammatory insults, but its role in acrylamide-induced neurotoxicity remains unknown.

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Buruli ulcer is an emerging chronic infectious skin disease caused by Mycobacterium ulcerans. Mycolactone, an exotoxin produced by the bacterium, is the only identified virulence factor so far, but the functions of this toxin and the mechanisms of disease progression remain unclear. By interfering Sec61 translocon, mycolactone inhibits the Sec61-dependent co-translational translocation of newly synthesized proteins, such as induced cytokines and immune cell receptors, into the endoplasmic reticulum.

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Acrylamide is a neurotoxicant in human and experimental animals. Interleukin-1β (IL-1β) is a proinflammatory cytokine known as a critical component of brain reaction to any insult or neurodegenerative pathologies, though its role in electrophile-induced neurotoxicity remains elusive. The aim of this study was to investigate the role of IL-1β in acrylamide-induced neurotoxicity in mice.

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Dendritic cell immunoreceptor (DCIR) is an inhibitory C-type lectin receptor that acts as a negative regulator in the immune system and bone metabolism. We previously revealed that DCIR deficiency enhanced osteoclastogenesis and antigen presentation of dendritic cells, and that asialo-biantennary N-glycan (NA2) functions as a ligand for DCIR. NA2 binding to DCIR suppressed murine and human osteoclastogenesis that occurs in the presence of M-CSF and RANKL.

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The skin is one of the major immune organs producing large amounts of proinflammatory and inflammatory cytokines in response to internal or exogenous stimuli, inducing systemic inflammation in various internal organs. In recent years, organ damage associated with inflammatory skin diseases such as psoriasis and atopic dermatitis has received increasing attention, and vascular disorder such as arteriosclerosis is one of the serious complications of chronic inflammatory skin diseases. However, the detailed mechanism of arteriosclerosis in dermatitis and the role of cytokines have not been clarified so far.

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Sepsis is a pathological condition that affects the metabolism of administered drugs, leading to changes in the duration and intensity of their intended efficacies. Proinflammatory cytokines downregulate the expression of cytochrome P450s (P450s). The effects of P450 expression under inflammatory conditions have been studied using prophlogistic substances such as lipopolysaccharide; however, few studies have focused on clinical models of sepsis.

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Dectin-1 (gene Clec7a), a receptor for β-glucans, plays important roles in the host defense against fungi and immune homeostasis of the intestine. Although this molecule is also suggested to be involved in the regulation of tumorigenesis, the role in intestinal tumor development remains to be elucidated. In this study, we find that azoxymethane-dextran-sodium-sulfate-induced and Apc-induced intestinal tumorigenesis are suppressed in Clec7a mice independently from commensal microbiota.

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Hepatic multidrug transporters expressed on the canalicular membrane play a role in the hepatobiliary excretion of xenobiotics and endogenous substrates. The aim of this study was to elucidate the role of pro-inflammatory cytokines in the regulation of hepatic drug transporter expression after cecal ligation and puncture (CLP), a valuable tool for studying polymicrobial sepsis, and to compare CLP with lipopolysaccharide (LPS) treatment. CLP reduced the expression of Mdr2/Abcb4, Mrp2/Abcc2, Bsep/Abcb11, Bcrp/Abcg2, and Mate1/Slc47a1 mRNAs in wild-type (WT) mouse livers in a time-dependent manner up to 48 h postoperation.

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Still's disease is a severe inflammatory syndrome characterized by fever, skin rash and arthritis affecting children and adults. Patients with Still's disease may also develop macrophage activation syndrome, a potentially fatal complication of immune dysregulation resulting in cytokine storm. Here we show that mTORC1 (mechanistic target of rapamycin complex 1) underpins the pathology of Still's disease and macrophage activation syndrome.

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Granulopoiesis in the bone marrow adjusts cellular output as demand for neutrophils changes. Reactive granulopoiesis is induced by profound neutropenia, but its mechanism remains to be clarified. We herein explored its mechanisms using mouse models of syngeneic hematopoietic stem cell transplantation (SCT) and 5-fluorouracil-induced neutropenia.

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Article Synopsis
  • Subcutaneous phaeohyphomycosis usually affects healthy individuals after trauma but can become severe in people with CARD9 deficiencies or those who have had transplants due to unclear protective mechanisms.
  • A patient with a severe case of this infection harbored harmful mutations in the CLEC7A gene, leading to impaired immune responses against the fungus Corynespora cassiicola.
  • Research using a mouse model revealed that both Dectin-1 and CARD9 are crucial for producing key immune signals (TNF-α and IL-1β) that help kill this fungus, and a study of additional patients showed that many had similar mutations affecting immune function.
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Periodontal tissue supports teeth in the alveolar bone socket via fibrous attachment of the periodontal ligament (PDL). The PDL contains periodontal fibroblasts and stem/progenitor cells, collectively known as PDL cells (PDLCs), on top of osteoblasts and cementoblasts on the surface of alveolar bone and cementum, respectively. However, the characteristics and lineage hierarchy of each cell type remain poorly defined.

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  • The text refers to a correction made to a specific article with the DOI: 10.3389/fimmu.2022.849155, indicating that there may have been an error or oversight in the original publication.
  • The correction is important for maintaining the accuracy and integrity of the scientific record related to the research presented in the article.
  • Readers looking for the corrected information or updates should refer to the corrected version of the article through its DOI link.
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Dendritic cell immunoreceptor (DCIR; Clec4a2), a member of the C-type lectin receptor family, plays important roles in homeostasis of the immune and bone systems. However, the intestinal role of this molecule is unclear. Here, we show that dextran sodium sulfate (DSS)-induced colitis and azoxymethane-DSS-induced intestinal tumors are reduced in Clec4a2 mice independently of intestinal microbiota.

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