Stem cells show intrinsic interferon signalling, which protects them from viral infections at all ages. In the ageing brain, interferon signalling also reduces the ability of stem cells to activate. Whether these functions are linked and at what time interferons start taking on a role in stem cell functioning is unknown.
View Article and Find Full Text PDFPopulations of stem, progenitor, or cancer cells show proliferative heterogeneity , comprising proliferating and quiescent cells. Consistent quantification of the quiescent subpopulation and progression of the proliferating cells through the individual phases of the cell cycle has not been achieved. Here, we describe CycleFlow, a method that robustly infers this comprehensive information from standard pulse-chase experiments with thymidine analogs.
View Article and Find Full Text PDFChronic cytomegalovirus (CMV) infection leads to long-term maintenance of extraordinarily large CMV-specific T cell populations. The magnitude of this so-called 'memory inflation' is thought to mainly depend on antigenic stimulation during the chronic phase of infection. However, by mapping the long-term development of CD8 T cell families derived from single naive precursors, we find that fate decisions made during the acute phase of murine CMV infection can alter the level of memory inflation by more than 1,000-fold.
View Article and Find Full Text PDFA major limitation preventing in vivo modulation of hematopoietic stem cells (HSCs) is the incomplete understanding of the cellular and molecular support of the microenvironment in regulating HSC fate decisions. Consequently, murine HSCs cannot be generated, maintained, or expanded in culture over extended periods of time. A significantly improved understanding of the bone marrow niche environment and its molecular interactions with HSCs is pivotal to overcoming this challenge.
View Article and Find Full Text PDFHematopoiesis is a paradigm for tissue development and renewal from stem cells. Experiments show that the maintenance of hematopoietic stem cells (HSCs) relies on signals from niche cells. However, it is not known how the size of the HSC compartment is set.
View Article and Find Full Text PDFThe regenerative capacity of hematopoietic stem cells (HSCs) is limited by the accumulation of DNA damage. Conditional mutagenesis of the histone 3 lysine 4 (H3K4) methyltransferase, , revealed that it is required for the expression of DNA damage recognition and repair pathways in HSCs. Specific deletion of in adult long-term (LT) HSCs is compatible with adult life and has little effect on the maintenance of phenotypic LT-HSCs in the bone marrow.
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