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Chang, Y.-J.

Publications and source records attributed to Chang, Y.-J..

2 recordsLinked to original sources

Three-dimensional genome structure and chromatin accessibility reorganization during in vivo induction of human T cell tolerance

Achieving T cell tolerance is a pivotal goal for the field of transplantation and autoimmune diseases. Here, we characterized the gene expression profiles, 3D genome architecture and chromatin accessibility in human steady-state and tolerant T cells, which had been induced in healthy donors by granulocyte-colony-stimulating factor in vivo. We provided the first high-resolution 3D genomic landscape of human tolerant T cells in vivo and identified highly expressed suppressor of cytokine signaling 1 (SOCS1), which is essential for maintaining T cell tolerance and was validated by ex vivo experiments. Mechanistically, SOCS1 is activated by STAT3, which mediates a new interaction between the SOCS1 locus and downstream super-enhancers and is accompanied by the disruption of the CTCF loop between the SOCS1 locus and upstream heterochromatin. This competitive regulation pattern between STAT3 and CTCF is present in the whole genome. Our study defines a regulatory model of transcription factors and provides insight into the induction of immune tolerance.

bioinformatics

Semilunar Granule Cells Maintain Distinct Dendritic Morphology and Inhibition through Postnatal Development and Receive Heightened Inhibition in Adolescence

Semilunar granule cells (SGCs) have been proposed as a morpho-functionally distinct class of hippocampal dentate projection neurons contributing to feedback inhibition and memory processing in juvenile rats. However, the structural and physiological features that can reliably classify granule cells (GCs) from SGCs through postnatal development remain unresolved. Focusing on postnatal days 11-13, 28-42, and >120, corresponding with human infancy, adolescence, and adulthood, we examined the somatodendritic morphology and inhibitory regulation in SGCs and GCs to determine the cell-type specific features. Unsupervised cluster analysis confirmed that morphological features reliably distinguish SGCs from GCs irrespective of animal age. SGCs maintain higher spontaneous inhibitory postsynaptic current (sIPSC) frequency than GCs from infancy through adulthood. Although sIPSC frequency in SGCs was particularly enhanced during adolescence, sIPSC amplitude and cumulative charge transfer declined from infancy to adulthood and were not different between GCs and SGCs. Extrasynaptic GABA current amplitude peaked in adolescence in both cell types and was significantly greater in SGCs than in GCs only during adolescence. Although GC input resistance was higher than in SGCs during infancy and adolescence, input resistance decreased with developmental age in GCs while it progressively increased in SGCs. Consequently, GCs input resistance was significantly lower than SGCs in adults. The data delineate the structural features that can reliably distinguish GCs from SGCs through development. The results reveal developmental differences in passive membrane properties and steady state inhibition between GCs and SGCs which could confound their use in classifying the cell types.

neuroscience