PT  - JOURNAL ARTICLE
AU  - Caroline Scott
AU  - Damien J. Downes
AU  - Jill M. Brown
AU  - Christian Babbs
AU  - Aude-Anais Olijnik
AU  - Matthew Gosden
AU  - Robert Beagrie
AU  - Ron Schwessinger
AU  - Christopher A. Fisher
AU  - Anna Rose
AU  - David J.P Ferguson
AU  - Errin Johnson
AU  - Quentin. A Hill
AU  - Steven Okoli
AU  - Raffaele Renella
AU  - Kate Ryan
AU  - Marjorie Brand
AU  - Jim Hughes
AU  - Noemi Roy
AU  - Douglas R. Higgs
AU  - Veronica J. Buckle
TI  - Modelling erythropoiesis in congenital dyserythropoietic anaemia type I (CDA-I)
AID  - 10.1101/744367
DP  - 2019 Jan 01
TA  - bioRxiv
PG  - 744367
4099  - http://biorxiv.org/content/early/2019/08/30/744367.short
4100  - http://biorxiv.org/content/early/2019/08/30/744367.full
AB  - We employ and extensively characterise an ex vivo culture system to study terminal erythroid maturation of CD34+ progenitors from the peripheral blood of normal individuals and patients with Congenital Dyserythropoietic Anaemia type 1 (CDA-I). Using morphological analysis, FACS analysis and the proteomic approach CyTOF, we analysed patient-derived erythroblasts stage-matched with those from healthy donors during the expansion phase and into early differentiation. In patient cells, aspects of disordered erythropoiesis manifest midway through differentiation, including increased proliferation and changes in the DNA accessibility profile. We also show that cultured erythroblasts from CDA-I patients recapitulate the pathognomic feature of this erythroid disorder with up to 40% of the cells having abnormal ‘spongy’ chromatin morphology by electron microscopy, as well as upregulation of GDF15, a marker of ineffective erythropoiesis. In the tertiary phase of culture, patient cells show significantly less enucleation and there is persistence of earlier erythroid precursors. Furthermore, the enucleation defect appears to be more severe in patients with mutations in C15orf41, as compared to the other known causative gene CDAN1, indicating a genotype/phenotype correlation in CDA-I. Such erythroblasts are a valuable resource for investigating the pathogenesis of this disease and provide the opportunity for streamlining diagnosis for CDA-I patients and ultimately other forms of unexplained anaemia.