Manager - Bioinformatics
Epigenome Technologies\, San Diego\, CA
Talk Tit le: Deciphering Single-Cell Chromatin Landscapes in the Human Immune Sys tem: A First Look
Host: Dr. Ting Wang
Abstract: Cellular i dentity and gene expression programs are imprinted and maintained by epigen etic mechanisms\, but precise mapping of histone-mediated regulatory factor s in tissues has been hindered by cell heterogeneity. Recent technological advances in single-cell histone profiling\, specifically single-cell Cut&Ta g and Paired-Tag methodologies\, now enable detailed mapping of chromatin l andscapes without prior cell sorting. Utilizing peripheral blood mononuclea r cells (PBMCs) from multiple donors\, we generated over 70\,000 single-cel l histone modification profiles (H3K4me1\, H3K4me3\, H3K27ac\, and H3K27me3 )\, accurately reflecting bulk epigenomic signatures and providing a detail ed preliminary atlas of chromatin states in circulating human immune cells.
More than 650\,000 regions of chromatin modification were identified \, grouping into approximately 120\,000 candidate cis-regulatory elements ( cCREs). Most cCREs exhibited widespread activity across immune populations\ , defining a core epigenomic signature\, while a sizeable subset displayed cell-type specificity indicative of roles in lineage commitment and functio nal identity. We highlighted regulatory regions demonstrating cell-specific bivalent chromatin signatures marked simultaneously by activating (H3K4me3 ) and repressive (H3K27me3) modifications\, suggesting poised regulatory st ates with potential for dynamic transcriptional responses.
Chromatin state clustering at transcription factor-binding sites\, particularly those bound by interferon regulatory factors (IRFs)\, revealed distinct activati on patterns correlated with immunological function and cell-type-specific r esponsiveness. These findings illustrate the capability of single-cell hist one profiling technologies to dissect immune regulatory networks\, offering powerful tools for identifying epigenetic signatures linked to immune func tion\, maturation\, and disease pathology.
LOCATION:Holden Auditorium GEO:38.636879;-90.262646 ORGANIZER;CN="Michelle Gibbs":MAILTO:gibbsm@wustl.edu URL;VALUE=URI:https://genetics.wustl.edu/events/event/chris/ ATTACH;FMTTYPE=image/jpeg:https://genetics.wustl.edu/app/uploads/2025/09/FLYER-HartlC-EpigenomeTech_816x1088.jpg END:VEVENT BEGIN:VTIMEZONE TZID:America/Chicago BEGIN:DAYLIGHT TZOFFSETFROM:-0600 TZOFFSETTO:-0500 DTSTART:20250309T080000 TZNAME:CDT END:DAYLIGHT END:VTIMEZONE END:VCALENDAR