Publications by authors named "Mio Hayama"
Medullary thymic epithelial cells (mTECs) play a crucial role in suppressing the onset of autoimmunity by eliminating autoreactive T cells and promoting the development of regulatory T cells in the thymus. Although mTECs undergo turnover in adults, the molecular mechanisms behind this process remain unclear. This study describes the direct and indirect roles of receptor activator of NF-κB (RANK) and CD40 signaling in TECs in the adult thymus.
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- Long-duration spaceflight can stress the skeletal and immune systems, but the specific response mechanisms are still not fully understood.
- A study with mice on the ISS evaluated how different gravitational conditions (microgravity, lunar gravity, and Earth gravity) affected their bone, thymus, and spleen over 25-35 days.
- Results showed that while bone density loss in microgravity was mostly restored in Earth gravity, lunar gravity only offered partial recovery; microgravity also caused thymus shrinkage, partially reversible by both lunar and Earth gravity but with ongoing gene expression issues.
Sphingosine 1-phosphate receptor 1 (S1PR1), a G protein-coupled receptor, is required for lymphocyte trafficking, and is a promising therapeutic target in inflammatory diseases. Here, we synthesize a competitive S1PR1 antagonist, KSI-6666, that effectively suppresses pathogenic inflammation. Metadynamics simulations suggest that the interaction of KSI-6666 with a methionine residue Met124 in the ligand-binding pocket of S1PR1 may inhibit the dissociation of KSI-6666 from S1PR1.
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- Autophagy is usually triggered by stress like starvation or mitochondrial damage, but some cells activate it through unclear ways.
- Researchers found that the protein C15ORF48 is crucial for activating this stress-independent autophagy, which helps maintain cell survival and reduces oxidative stress.
- Mice lacking C15orf48 show decreased autophagy in specific cells and develop autoimmune issues, highlighting the importance of C15ORF48 in regulating self-tolerance in the immune system.
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- * Acute total body irradiation affects the diversity and gene expression of mTECs, with a significant reduction in AIRE-expressing mTECs observed 15 days post-irradiation.
- * The study indicates that acute irradiation leads to long-lasting changes in mTEC properties, which might impair T cell selection in the thymus.
One hallmark of some autoimmune diseases is the variability of symptoms among individuals. Organs affected by the disease differ between patients, posing a challenge in diagnosing the affected organs. Although numerous studies have investigated the correlation between T cell antigen receptor (TCR) repertoires and the development of infectious and immune diseases, the correlation between TCR repertoires and variations in disease symptoms among individuals remains unclear.
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- Medullary thymic epithelial cells (mTECs) play a vital role in teaching T cells about the body's own tissues to prevent autoimmune responses, a process regulated by the transcription factor AIRE.
- Research using advanced techniques like scATAC-seq and scRNA-seq has identified a specific type of proliferating mTECs (AireCD80) that show distinct chromatin patterns and high levels of the AIRE protein and co-stimulatory molecules like CD80.
- These proliferating mTECs initially express fewer tissue-specific antigens (TSAs) but can transition to a quiescent state where they express higher levels of TSAs, indicating a key step in their development in the postnatal thym