Somatic stem cell heterogeneity: diversity in the blood, skin and intestinal stem cell compartments

Abstract

Somatic stem cells replenish many tissues throughout life to repair damage and to maintain tissue homeostasis. Stem cell function is frequently described as following a hierarchical model in which a single master cell undergoes self-renewal and differentiation into multiple cell types and is responsible for most regenerative activity. However, recent data from studies on blood, skin and intestinal epithelium all point to the concomitant action of multiple types of stem cells with distinct everyday roles. Under stress conditions such as acute injury, the surprising developmental flexibility of these stem cells enables them to adapt to diverse roles and to acquire different regeneration capabilities. This paradigm shift raises many new questions about the developmental origins, inter-relationships and molecular regulation of these multiple stem cell types.

F-box protein interactions with the hallmark pathways in cancer

“…This process culminates in terminal differentiation, which includes cell cycle exit, resulting in a specialized cell type (61,62). Whereas some cancer types, such as chronic myeloid leukaemia, show extensive proliferative defects but little effect on differentiation, most cancers are compromised in some way in both processes.…”

Hardwiring Stem Cell Communication through Tissue Structure

“…The stem cell niche was first conceptualized and proposed by Schofield to be the cellular environment that anchors stem cells and confers long-term self-renewing capacity not only to undifferentiated stem cells, but also to the progeny that occupy it (Schofield, 1978). Accordingly, studies in at least some mammalian tissues suggest that stem cells are composed of a heterogeneous population of cells that show different transcriptional profiles and self-renewing ability, but are functionally equivalent with respect to their capacity to maintain tissue during homeostasis and restore tissue upon injury (Goodell et al, 2015; Krieger and Simons, 2015; Wabik and Jones, 2015). Therefore for the purpose of this review, we will use this original proposed definition of tissue stem cells to discuss the interaction of these cells with their environment and to highlight work that underlines the central role of communication in regulating stem cell behavior and function.…”

Intestinal Organoids—Current and Future Applications

“…CBC cells are the proliferative engines that drive cellular production in the crypts: they divide daily, with frequent turnover. +4 cells have been redefined as reserve or quiescent ISCs (qISCs): they divide infrequently under homeostatic conditions but can be induced to produce new CBC cells in response to injury or other stimuli [10].…”