We study human developmental hematopoiesis in vitro using human pluripotent stem cells (hPSCs). Pluripotent stem cells have proven to be an invaluable tool to mimic development in a dish. Our lab uses in vitro differentiation strategies to elucidate the intrinsic and extrinsic signalling driving blood development, and those signals interact to orchestrate blood development. We are particularly interested in the endothelial-to-hematopoietic transition, or EHT. In this process, a subset of endothelial cells, known as hemogenic endothelium, remodel their transcriptomic while rounding up to become a hematopoietic stem or progenitor cell. Understanding the mechanisms driving blood stem and progenitor cells development during embryonic life will improve the quality and the types of cells we can produce in the laboratory for cell therapy.

Aims and areas of interest

Singe-cell transcriptomics and machine learning
We have shown that in vitro differentiation of human pluripotent stem cells mimics the developmental stages leading to the formation of blood progenitors that are transcriptionally very similar to those of the embryo. Furthermore, combining machine learning with single-cell transcriptomics, we found a rare and transient population of HSC-like cells (Fidanza et al., 2020). We aim to improve the phenotype by targeting pathways and genes that we found to be different between in vitro derived HSC-like cells and functional HSCs that develop within the embryo.

Transcriptional remodelling
We are particularly interested in the transcriptional control during the endothelial-to-hematopoietic transition, or EHT. We aim to understand what makes endothelial cells become hemogenic and how they progress to become blood cells. To understand the transcriptional control during this transition, we have developed an iPSCs-based endogenous gene activation CRISPR tool that we have used to remodel the gene expression (Fidanza et al., 2017; Petazzi et al., 2019; Petazzi et al., 2022). Using this approach, we want to learn the gene network important for the EHT and improve the proportion of endothelial cells that become hemogenic and eventually give rise to blood.

We believe that those who care for science share! Contact us if you want to use any of our tools/codes/datasets. If your interest in science aligns with us, get in touch. We are always looking for enthusiastic scientists, from students to postdocs.
Group members
Nora Aljindan, PhD Student
Ewen Egan, PhD Student
Maja Gabric, PhD Student
Telma Ventura, Research Assistant
Collaborators
Professor Elisa Laurenti, Cambridge Stem Cell Institute
Dr Patrick Stumpf, RWTH Aachen University
Professor Katrin Ottersbach, University of Edinburgh
Dr Nicola Romanò, University of Edinburgh
Professor Pablo Menendez, Josep Carreras Leukaemia Research Institute
Dr Raquel Espin Palazon, Iowa State University
Professor Robert Semple, University of Edinburgh
Publications | ||
Peer Reviewed Articles | ||
Fidanza, A. et al. (2017) ‘An all-in-one UniSam vector system for efficient gene activation’, Scientific Reports. Nature Publishing Group, 7(1), p. 6394. doi: 10.1038/s41598-017-06468-6. | View Publication | |
Fidanza, A. et al. (2020) ‘Single cell analyses and machine learning define hematopoietic progenitor and HSC-like cells derived from human PSCs.’, Blood. Blood, 136(25), pp. 2893–2904. doi: 10.1182/blood.2020006229. | View Publication | |
Petazzi , P, Torres, R, Fidanza, A, Roca-Ho, H, Gutierrez-Aguera, F, Diaz de la Guardia, R, Lopez-Millan, B, Bigas, A, Forrester, LM, Bueno, C, Menendez, P. (2019) ‘Robustness of dead Cas9 activators in human pluripotent and mesenchymal stem cells.’, Molecular Therapy Nucleic Acid - resubmitted revised version. doi: 10.1016/j.omtn.2020.02.009. | View Publication | |
Petazzi, P. et al. (2022) ‘Arterial cells support the development of human hematopoietic progenitors in vitro via secretion of IGFBP2’, bioRxiv. Cold Spring Harbor Laboratory, p. 2022.10.04.510611. doi: 10.1101/2022.10.04.510611. | View Publication | |
Petazzi, P. and Menendez, P. (2020) ‘A NEWral approach for HSC production in vitro?’, Blood. American Society of Hematology, 136(25), pp. 2845–2847. doi: 10.1182/blood.2020007864. | View Publication | |