Basic Research on Candida Species.

Candida species are common human pathogens that cause a wide range of diseases ranging from superficial to invasive candidiasis. However, basic studies focusing on the mechanisms underlying these diseases are limited. This article reviews our previous research on the mechanisms of superficial and invasive candidiasis, the virulence of Candida species, and Candida species fitness to hosts.

Glycolipid antigen recognition by invariant natural killer T cells and its role in homeostasis and antimicrobial responses.

Due to the COVID-19 pandemic, the importance of developing effective vaccines has received more attention than ever before. To maximize the effects of vaccines, it is important to select adjuvants that induce strong and rapid innate and acquired immune responses. Invariant natural killer T (iNKT) cells, which constitute a small population among lymphocytes, bypass the innate and acquired immune systems through the rapid production of cytokines after glycolipid recognition; hence, their activation could be used as a vaccine strategy against emerging infectious diseases.

IL-27 regulates the differentiation of follicular helper NKT cells via metabolic adaptation of mitochondria.

Invariant natural killer T (iNKT) cells are innate-like T lymphocytes that express an invariant T cell receptor α chain and contribute to bridging innate and acquired immunity with rapid production of large amounts of cytokines after stimulation. Among effecter subsets of iNKT cells, follicular helper NKT (NKT) cells are specialized to help B cells. However, the mechanisms of NKT cell differentiation remain to be elucidated.

Instantaneous Clearing of Biofilm (iCBiofilm): an optical approach to revisit bacterial and fungal biofilm imaging.

Whole-biofilm imaging at single-cell resolution is necessary for system-level analysis of cellular heterogeneity, identification of key matrix component functions and response to immune cells and antimicrobials. To this end, we developed a whole-biofilm clearing and imaging method, termed instantaneous clearing of biofilm (iCBiofilm). iCBiofilm is a simple, rapid, and efficient method involving the immersion of biofilm samples in a refractive index-matching medium, enabling instant whole-biofilm imaging with confocal laser scanning microscopy.

Small-Molecule-Induced Activation of Cellular Respiration Inhibits Biofilm Formation and Triggers Metabolic Remodeling in Staphylococcus aureus.

Staphylococcus aureus, a major pathogen of community-acquired and nosocomial-associated infections, forms biofilms consisting of extracellular matrix-embedded cell aggregates. S. aureus biofilm formation on implanted medical devices can cause local and systemic infections due to the dispersion of cells from the biofilms.

Staphylococcus aureus utilizes environmental RNA as a building material in specific polysaccharide-dependent biofilms.

Biofilms are surface-bound microbial communities that are typically embedded in a matrix of self-produced extracellular polymeric substances and can cause chronic infections. Extracellular DNA is known to play a crucial role in biofilm development in diverse bacteria; however, the existence and function of RNA are poorly understood. Here, we show that RNA contributes to the structural integrity of biofilms formed by the human pathogen Staphylococcus aureus.

Common Features and Intra-Species Variation of Strains, and Emended Description of the Species.

is a new species coined in 2020 as the fifth species of genus , which includes . The species is predicted as a minor but common member of skin microbiome and includes a group tentatively named as "". The description of the species has been provided only with a single strain.

α-galactosylceramide-stimulated invariant natural killer T-cells play a protective role in murine vulvovaginal candidiasis by Candida albicans.

Background: Vulvovaginal candidiasis is a common superficial candidiasis; however, a host's immunological mechanism against vaginal Candida infection remains unknown.

Objectives: In this study, we aimed to elucidate the effect of iNKT cell activation on vulvovaginal candidiasis.

Methods: Using a vulvovaginal candidiasis model with estrogenized mice, we evaluated the fungal burden and number of leukocyte infiltrations in the vaginal lavage of wild-type C57BL/6J mice after Candida albicans inoculation.

Acsbg1-dependent mitochondrial fitness is a metabolic checkpoint for tissue T cell homeostasis.

Regulatory T (T) cells are critical for immunological tolerance and immune homeostasis. T cells strongly rely on mitochondrial metabolism and show a lower level of glycolysis. However, little is known about the role of lipid metabolism in the regulation of T cell homeostasis.

SCD2-mediated monounsaturated fatty acid metabolism regulates cGAS-STING-dependent type I IFN responses in CD4 T cells.

Host lipid metabolism and viral responses are intimately connected. However, the process by which the acquired immune systems adapts lipid metabolism to meet demands, and whether or not the metabolic rewiring confers a selective advantage to host immunity, remains unclear. Here we show that viral infection attenuates the expression of genes related to lipid metabolism in murine CD4 T cells, which in turn increases the expression of antiviral genes.

Hierarchical Model for the Role of J-Domain Proteins in Distinct Cellular Functions.

In Escherichia coli, the major bacterial Hsp70 system consists of DnaK, three J-domain proteins (JDPs: DnaJ, CbpA, and DjlA), and nucleotide exchange factor GrpE. JDPs determine substrate specificity for the Hsp70 system; however, knowledge on their specific role in bacterial cellular functions is limited. In this study, we demonstrated the role of JDPs in bacterial survival during heat stress and the DnaK-regulated formation of curli-extracellular amyloid fibers involved in biofilm formation.

Intensive diagnostic management of coronavirus disease 2019 (COVID-19) in academic settings in Japan: challenge and future.

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), first emerged in Wuhan, China, and has spread globally to most countries. In Japan, the first COVID-19 patient was identified on January 15, 2020. By June 30, the total number of patients diagnosed with COVID-19 reached 18,000.

Roles of lytic transglycosylases in biofilm formation and β-lactam resistance in methicillin-resistant .

is responsible for numerous community outbreaks and is one of the most frequent causes of nosocomial infections with significant morbidity and mortality. While the function of lytic transglycosylases (LTs) in relation to cell division, biofilm formation, and antibiotic resistance has been determined for several bacteria, their role in remains largely unknown. The only known LTs in are immunodominant staphylococcal antigen A (IsaA) and D protein (SceD).

Identification of a Novel Variant Form of Aspergillus fumigatus CalC and Generation of Anti-CalC Monoclonal Antibodies.

Aspergillus fumigatus is a critical human fungal pathogen that infects the host via inhalation of airborne conidia. These conidia then germinate to form filamentous hyphae, which secrete various elements to survive in the host lung.Elements such as proteins secreted by A.

Efficacy of T-2307, a novel arylamidine, against ocular complications of disseminated candidiasis in mice.

Objectives: T-2307, a novel arylamidine, shows broad-spectrum activity against pathogenic fungi, including Candida albicans. Ocular candidiasis is one of the serious complications associated with Candida bloodstream infection and is known to be refractory to conventional antifungal agents. The aim of the present study was to clarify the effectiveness of T-2307 against ocular candidiasis using a mouse model.

Redundant and Distinct Roles of Secreted Protein Eap and Cell Wall-Anchored Protein SasG in Biofilm Formation and Pathogenicity of Staphylococcus aureus.

Chronic and fatal infections caused by are sometimes associated with biofilm formation. Secreted proteins and cell wall-anchored proteins (CWAPs) are important for the development of polysaccharide-independent biofilms, but functional relationships between these proteins are unclear. In the present study, we report the roles of the extracellular adherence protein Eap and the surface CWAP SasG in MR23, a clinical methicillin-resistant isolate that forms a robust protein-dependent biofilm and accumulates a large amount of Eap in the extracellular matrix.

Neutrophil-mediated antifungal activity against highly virulent Cryptococcus gattii strain R265.

Vaccine-induced immune responses, including neutrophil, macrophage, and T-cell responses, ameliorate cryptococcosis caused by Cryptococcus gattii. However, whether neutrophils can exert fungicidal activity against C. gattii remains to be elucidated.