Stem cells are the body’s raw materials – cells from which all other specialized cells are generated (cardiac cells, blood cells…). They have the potential to differentiate into multiple tissues. They also have the capacity of long-term self-renewal. No other cell type in the body has the natural ability to generate new cell types.
Literature
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2 Krause, DS et al. (1996), CD34: structure, biology, and clinical utility. Blood 87:1–13
3 Lagasse, E et al. (2000), Purified hematopoietic stem cells can differentiate into hepatocytes in vivo. Nat Med 6:1229–1234. https://doi.org/10.1038/81326
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6 Pasquet et al., Cytotherapy, 2009;11(8):1002-15
7 Wang, S-J et al. (2016), he Chondrogenic Potential of Progenitor Cells Derived from Peripheral Blood: A Systematic Review. Stem Cells Dev 25:1195–1207
8 Wojakowski et al. (2004), Mobilization of CD34/CXCR4+ […] Circulation, 110, 3213–3220CD34+ are safe
– Easily found in bone marrow or peripheral blood
– Naturally mobilized after myocardial infraction
– Capacity to regenerate cardiac tissues
– Are safe
Endogenous CD34+ cells are mobilized from the bone marrow into the peripheral blood after an acute myocardial infarction (AMI). Chemokines secreted from the damaged heart tissue attract the CD34+ cells to home to the heart and promote repair. It has been shown that after AMI, the concentration of CD34+ cells is significantly correlated with improvement in heart function (left ventricular ejection fraction). The mobilized CD34+ cells promote heart regeneration by two different mechanisms. First, there is a paracrine effect, where CD34+ cells secrete growth factors (such as vascular endothelial growth factor) and exosomes containing pro-angiogenic miRNAs that promote neovascularization by the formation of new blood vessels. Second, there is tissue repair, by the proliferation and differentiation of CD34+ cells into cardiomyocytes and endothelial cells.
CellProthera was created for the development, registration and marketing of innovative therapeutic solutions for the regeneration of organs damaged by disease or trauma from autologous blood peripheral stem cells. A very successful Proof of Concept trial showed structural and functional regeneration of myocardial tissue as well as reperfusion of an infarct zone after a recent Acute Myocardial Infarct (AMI). The final cell product ProtheraCytes® is made of CD34+ stem cells which have been confirmed to have potential for regeneration of various damaged tissues. ProtheraCytes® is now registered as an ATMP – Advanced Therapy Medicinal Product – within the classification of Tissue Engineered product by the European Medicines Agency.The therapeutic potential of ProtheraCytes® comes from two simultaneous mechanisms, a combination of paracrine effect and cell differentiation. The inflammatory scar in acute myocardial infarction secretes cardioactive chemokines which activate transplanted CD34+ cells. Activated CD34+ cells release soluble paracrine factors and exosomes that can enhance the proliferation of resident cardiomyocytes and support angiogenesis, thus reducing fibrosis and attenuating remodeling. A subpopulation of CD34+ cells express markers of endothelial and cardiomyocyte progenitor cells (Pasquet et al 2009) and the scar chemokines induce the commitment of CD34+ along the endothelial and cardiac pathways (Sahoo et al., 2011).