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Niec, R.

Publications and source records attributed to Niec, R..

2 recordsLinked to original sources

Epigenetic Memory of COVID-19 in Innate Immune Cells and Their Progenitors

Severe coronavirus disease 2019 (COVID-19) is characterized by systemic inflammation and can result in protracted symptoms. Robust systemic inflammation may trigger persistent changes in hematopoietic cells and innate immune memory through epigenetic mechanisms. We reveal that rare circulating hematopoietic stem and progenitor cells (HSPC), enriched from human blood, match the diversity of HSPC in bone marrow, enabling investigation of hematopoiesis and HSPC epigenomics. Following COVID-19, HSPC retain epigenomic alterations that are conveyed, through differentiation, to progeny innate immune cells. Epigenomic changes vary with disease severity, persist for months to a year, and are associated with increased myeloid cell differentiation and inflammatory or antiviral programs. Epigenetic reprogramming of HSPC may underly altered immune function following infection and be broadly relevant, especially for millions of COVID-19 survivors. One Sentence SummaryTranscriptomic and epigenomic analysis of blood reveal sustained changes in hematopoiesis and innate immunity after COVID-19. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=197 HEIGHT=200 SRC="FIGDIR/small/479588v1_ufig1.gif" ALT="Figure 1"> View larger version (54K): org.highwire.dtl.DTLVardef@1ffe42dorg.highwire.dtl.DTLVardef@dd4868org.highwire.dtl.DTLVardef@1bcae8borg.highwire.dtl.DTLVardef@674e85_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

A lymphatic-stem cell interactome regulates intestinal stem cell activity

Barrier epithelia depend on resident stem cells for homeostasis, defense and repair. Intestinal stem cells (ISCs) of the small and large intestines respond to their local microenvironments (niches) to fulfill a continuous demand for tissue turnover, yet the complexity of their niches is still unfolding. Here, we report an extensive lymphatic network that intimately associates with ISCs within these niches. Devising a lymphatic:organoid coculture system, we show that lymphatic-secreted factors maintain ISCs while inhibiting precocious differentiation. Employing a new deconvolution algorithm, BayesPrism, to pair single-cell and spatial transcriptomics, we cartograph the lymphatic ligand:ISC receptor interactomes at high resolution. We unearth crypt lymphatics as a major source of WNT-signaling factors (WNT2, R-SPONDIN-3) known to drive ISC behavior, and REELIN, a hitherto unappreciated ISC regulator secreted by crypt lymphatics. Together, our studies expose lymphatics as a central hub for niche factors that govern the regenerative potential of ISCs.

cell biology↗