No abstract

Stem and progenitor cells have the capacity to balance self-renewal and differentiation. Hematopoietic myeloid progenitors replenish more than 25 billion terminally differentiated neutrophils every day under homeostatic conditions and can increase output in response to stress or infection. At what point along the spectrum of maturation do progenitors lose capacity for self-renewal and become irreversibly committed to differentiation? Using a system of conditional myeloid development that can be toggled between self-renewal and differentiation, we interrogated determinants of this "point of no return" in differentiation commitment. Irreversible commitment is due primarily to loss of open regulatory site access and disruption of a positive feedback transcription factor activation loop. Restoration of the transcription factor feedback loop extends the window of cell plasticity and alters the point of no return. These findings demonstrate how chromatin state enforces and perpetuates cell fate and identifies potential avenues for manipulating cell identity.

Combined epigenetic and metabolic perturbations induce myeloid differentiationCombination treatment alters nucleotide, lipid, and gene expression profiles Combination treatment induces differentiation of human acute myeloid leukemia cells

Duchenne Muscular Dystrophy (DMD) is a genetic disorder involving progressive muscle deterioration leading to loss of mobility, cardiomyopathy, and respiratory complications leading to an early death by the fourth decade of life. Males are affected more often as DMD results from a mutation in the dystrophin gene residing on the X chromosome. The DMD genetic mutation results in a complete functional lack of dystrophin, which culminates as an inadequate connection between the intracellular actin filaments and the extracellular skeleton of muscle. Boys affected by DMD clinically present with muscle weakness before age five, are often wheelchair-bound by age 12, and rarely survive beyond the third decade of life. Traditional treatment strategies have focused primarily on quality-of-life improvement and have included the use of glucocorticoids and physical therapy. No cure currently exists, however many novel treatments for DMD are currently being explored. Some of these involve gene therapy, exon skipping, stop codon skipping, CRISPR technology interventions, and the use of a retinal dystrophin isoform. In this comprehensive review, we recapitulate the literature findings to summarize the history, epidemiology, genetics, clinical presentation, diagnosis, and current and future strategies for the treatment of Duchenne Muscular Dystrophy.