Publications by authors named "Yumi Tsutsui"
T-cell deficiency induces deficits in social behavior and dyslipidemia in mice.
Biochem Biophys Res Commun
March 2023
Patients with neuropsychiatric disorders often exhibit an altered metabolic status. However, the underlying factors that induce behavioral and metabolic dysfunctions remain poorly understood. Therefore, we investigated whether behavioral and metabolic alterations could be induced in immunodeficient conditions.
View Article and Find Full Text PDFArticle Synopsis
- Small, soluble metabolites like GABA, produced by activated B cells, can influence nearby cells and play a role in immune responses.
- GABA promotes the differentiation of monocytes into anti-inflammatory macrophages, which help suppress CD8 T cell activity and secrete interleukin-10.
- Research shows that reducing B cell activity or GABA production can enhance anti-tumor responses, highlighting the potential of small metabolites as therapeutic targets for regulating the immune system.
Article Synopsis
- Activated T cells change their metabolism, but the overall effects of their sustained activation on the body haven't been fully studied.
- In mice lacking the PD-1 receptor (Pdcd1 mice), heightened T cell activity led to a decrease in amino acids in the serum, as these amino acids accumulated in the T cells instead.
- This depletion of amino acids, particularly tryptophan and tyrosine, resulted in lower levels of key neurotransmitters like serotonin and dopamine in the brain, leading to increased anxiety and fear behaviors.
Foxp3(+) T cells play a critical role for the maintenance of immune tolerance. Here we show that in mice, Foxp3(+) T cells contributed to diversification of gut microbiota, particularly of species belonging to Firmicutes. The control of indigenous bacteria by Foxp3(+) T cells involved regulatory functions both outside and inside germinal centers (GCs), consisting of suppression of inflammation and regulation of immunoglobulin A (IgA) selection in Peyer's patches, respectively.
View Article and Find Full Text PDFImmunoglobulin A (IgA) is essential to maintain the symbiotic balance between gut bacterial communities and the host immune system. Here we provide evidence that the inhibitory co-receptor programmed cell death-1 (PD-1) regulates the gut microbiota through appropriate selection of IgA plasma cell repertoires. PD-1 deficiency generates an excess number of T follicular helper (T(FH)) cells with altered phenotypes, which results in dysregulated selection of IgA precursor cells in the germinal center of Peyer's patches.
View Article and Find Full Text PDFBionanocapsules (BNCs) are hollow nanoparticles that are composed of L protein (the hepatitis B virus surface antigen) and show specific affinity for human hepatocytes. The pre-S1 peptide displayed on the surface of BNCs is the specific ligand for binding to the receptor on human hepatocytes. Therefore, BNCs are not delivered to other tissues, such as the brain.
View Article and Find Full Text PDF