A Hierarchy in Reprogramming Capacity in Different Tissue Microenvironments: What We Know and What We Need to Know

Abstract

Ectopic expression of certain transcription factors induces reprogramming of somatic cells to a pluripotent state. A number of studies have shed light on the reprogramming capacity of various cell populations. As a result, it has been shown that stem/progenitor cells derived from organs of all germ layers exhibit a superior reprogramming efficiency compared to their differentiated progeny. Although proliferative capacity and endogenous expression levels of pluripotency factors are likely to be involved in this superiority, the detailed molecular understanding remains elusive so far. Recently, we have shown that the BAF-complex (BAF155 and Brg1), mediating epigenetic changes during reprogramming, is critical for the increased reprogramming efficiency of liver progenitor cells. In this review, we summarize recently acquired findings of the increased reprogramming capacity of adult stem/progenitor cell populations compared to their differentiated counterparts and discuss the potential mechanisms involved.

Cellular Ontogeny and Hierarchy Influence the Reprogramming Efficiency of Human B Cells into Induced Pluripotent Stem Cells

“…A number of studies have revealed that immature cells (stem/progenitors) exhibit a superior reprogramming efficiency as compared to their differentiated progeny [12,13,25,26]. Our data indicates that throughout B-cell development, cellular hierarchy also influences reprogramming efficiency into iPSCs.…”

A Comparative View on Human Somatic Cell Sources for iPSC Generation

“…Nevertheless, some disadvantages of reprogramming fibroblasts such as their relatively low reprogramming efficiency and especially the need of uncomfortable biopsies have led to a search for other cell sources. The molecular properties of the different cell types leading to variations in the reprogramming efficiency have been reviewed in [14]. Publications describe, amongst others, three relatively easy to obtain cell types, that is, blood cells [15], exfoliated renal tubular epithelial cells, obtained from urine [16], and keratinocytes from plucked hair [17].…”

Definitive Endoderm Formation from Plucked Human Hair-Derived Induced Pluripotent Stem Cells and SK Channel Regulation

“…However, understanding early fate decision events, such as segregation of the three germ layers, is a prerequisite for regenerative medicine [1–5]. The advent of induced pluripotent stem cells and their unique features of unlimited self-renewal and nonrestricted differentiation capacity marked a milestone in the battle to dissect such processes—directly in the context of human development [6–8]. Given the incredible accordance of embryonic development in vivo and its respective model system in vitro , it is not surprising that most of the currently available pluripotent stem cell differentiation protocols make use of physiological, stage-specific signalling clues in order to recapitulate development of all three germ layers: ectoderm, mesoderm, and endoderm.…”