Mucosal mast cells (MMCs) are distinguished from connective tissue mast cells (MCs) by the specific cell-surface expression of integrin CD103 (also known as integrin αE/β7; αE is encoded by Itgae) and mast cell protease 1 and 2 (Mcpt1 and Mcpt2, respectively). Although the expression of the Mcpt1 and Mcpt2 genes is cooperatively regulated by the transcription factor GATA-binding protein 2 (GATA2) and transforming growth factor beta (TGF-β) signaling in MMCs, the transcriptional mechanism of the cell-surface expression of CD103 remains unknown. We herein found that surface CD103 and Itgae mRNA levels were significantly increased by the knockdown (KD) of Gata2 in mouse bone marrow-derived MCs (BMMCs), which was accelerated by TGF-β stimulation.
View Article and Find Full Text PDFThis study conducted an experiment on chicken infection with rotavirus A (RVA) strains.Two wild bird-derived RVA strains (RK1 and PO-13) caused diarrhoea in young chickens.The enteropathogenicity of these strains was comparable to that of a chicken strain.
View Article and Find Full Text PDFComplete genome sequences of four torque teno virus (TTV) (family Anelloviridae) isolates were obtained from the feces of two raccoon dogs (Nyctereutes procyonoides) and two red foxes (Vulpes vulpes) in Gifu Prefecture, Japan. The ORF1 nucleotide sequences of these four viruses, named Raccoon dog_Fe_1, Raccoon dog_Fe_2, Fox_Fe_1, and Fox_Fe_2, were different from those of known TTVs but similar to those of TTVs derived from masked palm civet_Pl-TTV9-1 (59.8 %), masked palm civet_Pl-TTV3 (56.
View Article and Find Full Text PDFUnlabelled: The rabies virus large (L) protein interacts with its cofactor phosphoprotein (P protein) to function as an RNA-dependent RNA polymerase (RdRp). The C-terminal domain (CTD) of the L protein plays a critical role in P protein binding. We previously reported that the highly conserved NPYNE sequence in the hydrophilic region of the CTD (positions 1929-1933 of the L protein [L1929-1933]) is important for both P protein binding and RdRp function.
View Article and Find Full Text PDFRabies vaccines require repeated immunization to robustly elicit neutralizing antibodies that prevent fatal diseases. Here, we analyzed rabies glycoprotein antibody repertoires at both polyclonal and monoclonal levels following repeated vaccination. Booster vaccination dramatically elevated the neutralizing activity of recalled antibodies, primarily targeting an immunodominant site III epitope with hydrophilic and rugged structures.
View Article and Find Full Text PDFHere, we examined the immunomodulating effects of Heyndrickxia coagulans SANK70258 (SANK70258). Mouse splenocytes treated with γ-ray-irradiated SANK70258 produced higher levels of interferon (IFN)-γ than those with 7 types of lactic acid bacteria. IFN-γ was mainly produced by natural killer (NK) cells, involving IL-12/IL-23, dendritic cells (DCs), and NF-κB signaling.
View Article and Find Full Text PDFBasophils and mast cells (MCs) play an important role in immune responses against allergens and parasitic infection. To elucidate the mechanisms that determine the commitment between basophils and mast cell (MCs), transcription factors and epigenetic modifications regulating the gene expression of basophil-specific enzymes, Mcpt8 and Mcpt11, were analyzed using bone marrow-derived (BM) cells containing basophils and MCs. Knockdown (KD) and overexpression experiments revealed that the transcription factor C/EBPα positively regulated the gene expression of Mcpt8 and Prss34 (encoding Mcpt11).
View Article and Find Full Text PDFWest Nile virus (WNV) is a mosquito-borne flavivirus that causes encephalitis in humans and infects crocodiles, resulting in rashes and neurological signs. In Zambia, two distinct lineages of WNV have been detected in neighbouring areas: lineage 2 in mosquitoes and lineage 1a in farmed crocodiles. Considering the risk of direct or vector-mediated WNV transmission from crocodiles to mammals, it is necessary to elucidate the pathogenicity of WNV strains derived from crocodiles.
View Article and Find Full Text PDFRabies is a fatal neurological disorder caused by rabies virus (RABV) infection. Approximately 60,000 patients die from rabies annually, and there are no effective treatments for this disease. Nucleoside analogs are employed as antiviral drugs based on their broad antiviral spectrum, and certain nucleoside analogs have been reported to exhibit anti-RABV activity.
View Article and Find Full Text PDFAvian rotaviruses A (RVAs) are occasionally transmitted to animals other than the original hosts across species barriers. Information on RVAs carried by various bird species is important for identifying the origin of such interspecies transmission. In this study, to facilitate an understanding of the ecology of RVAs from wild birds, we characterized all of the genes of an RVA strain, JC-105, that was detected in a fecal sample of a large-billed crow (Corvus macrorhynchos) in Japan.
View Article and Find Full Text PDFShort-chain fatty acids (SCFAs) are produced by the intestinal microbiota during the fermentation of dietary fibers as secondary metabolites. Several recent studies reported that SCFAs modulate the development and function of immune-related cells. However, the molecular mechanisms by which SCFAs regulate mast cells (MCs) remain unclear.
View Article and Find Full Text PDFAkabane virus (AKAV) is a member of the genus Orthobunyavirus, family Peribunyaviridae. In addition to AKAV strains that cause fetal Akabane disease, which is characterized by abortion in ruminants, some AKAV strains cause postnatal infection characterized by nonsuppurative encephalomyelitis in ruminants. Here, we focused on the NSs protein, a virulence factor for most viruses belonging to the genus Orthobunyavirus, and we hypothesized that this protein would act as a neurovirulence factor in AKAV strains causing postnatal encephalomyelitis.
View Article and Find Full Text PDFJ Occup Health
December 2023
Objective: This study aimed to develop and validate a Japanese version of the Occupational Future Time Perspective scale (OFTP-J) and assess its structural validity, construct validity, internal consistency, and test-retest reliability among Japanese workers.
Methods: The online survey was conducted with 2046 participants who met the eligibility criteria. The Japanese version of the OFTP scale was developed through translation and back-translation processes.
Live rabies vaccines have advantageous features that can facilitate mass vaccination for dogs, the most important reservoirs/transmitters of rabies. However, some live vaccine strains have problems in their safety, namely, risks from the residual pathogenicity and the pathogenic reversion of live vaccine strains. The reverse genetics system of rabies virus provides a feasible option to improve the safety of a live vaccine strain by, for example, artificially introducing attenuating mutations into multiple viral proteins.
View Article and Find Full Text PDFViral protein assembly and virion budding are tightly regulated to enable the proper formation of progeny virions. At this late stage in the virus life cycle, some enveloped viruses take advantage of the host endosomal sorting complex required for transport (ESCRT) machinery, which contributes to the physiological functions of membrane modulation and abscission. Bullet-shaped viral particles are unique morphological characteristics of rhabdoviruses; however, the involvement of host factors in rhabdovirus infection and, specifically, the molecular mechanisms underlying virion formation are not fully understood.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
April 2023
Viruses form extensive interfaces with host proteins to modulate the biology of the infected cell, frequently via multifunctional viral proteins. These proteins are conventionally considered as assemblies of independent functional modules, where the presence or absence of modules determines the overall composite phenotype. However, this model cannot account for functions observed in specific viral proteins.
View Article and Find Full Text PDFIn the present study, we evaluated the effects of kaempferol on bone marrow-derived mast cells (BMMCs). Kaempferol treatment significantly and dose-dependently inhibited IgE-induced degranulation, and cytokine production of BMMCs under the condition that cell viability was maintained. Kaempferol downregulated the surface expression levels of FcεRI on BMMCs, but the mRNA levels of FcεRIα, β, and γ-chains were not changed by kaempferol treatment.
View Article and Find Full Text PDFDendritic cells (DCs), which are typical antigen-presenting cells, localize to various sites in the body, particularly the front line of infection as sentinels, and are involved in innate and adaptive immune responses. Although the functions of DCs, such as pathogen-induced cytokine production and antigen-specific T cell activation, are important for host defenses against infection and tumorigenesis, the hyper- and/or extended activation of DCs leads to inflammatory and autoimmune diseases. In the present study, β-damascone, a major ingredient of rose fragrance, was selected from an aroma library as a candidate compound that suppresses antigen-induced immune responses.
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