Expansion of Umbilical Cord Blood Aldehyde Dehydrogenase Expressing Cells Generates Myeloid Progenitor Cells that Stimulate Limb Revascularization.
David M PutmanTyler T CooperStephen E ShermanAyesh K SeneviratneMark HewittGillian I BellDavid A HessPublished in: Stem cells translational medicine (2017)
Uncompromised by chronic disease-related comorbidities, human umbilical cord blood (UCB) progenitor cells with high aldehyde dehydrogenase activity (ALDHhi cells) stimulate blood vessel regeneration after intra-muscular transplantation. However, implementation of cellular therapies using UCB ALDHhi cells for critical limb ischemia, the most severe form of severe peripheral artery disease, is limited by the rarity (<0.5%) of these cells. Our goal was to generate a clinically-translatable, allogeneic cell population for vessel regenerative therapies, via ex vivo expansion of UCB ALDHhi cells without loss of pro-angiogenic potency. Purified UCB ALDHhi cells were expanded >18-fold over 6-days under serum-free conditions. Consistent with the concept that ALDH-activity is decreased as progenitor cells differentiate, only 15.1% ± 1.3% of progeny maintained high ALDH-activity after culture. However, compared to fresh UCB cells, expansion increased the total number of ALDHhi cells (2.7-fold), CD34+ /CD133+ cells (2.8-fold), and hematopoietic colony forming cells (7.7-fold). Remarkably, injection of expanded progeny accelerated recovery of perfusion and improved limb usage in immunodeficient mice with femoral artery ligation-induced limb ischemia. At 7 or 28 days post-transplantation, mice transplanted with expanded ALDHhi cells showed augmented endothelial cell proliferation and increased capillary density compared to controls. Expanded cells maintained pro-angiogenic mRNA expression and secreted angiogenesis-associated growth factors, chemokines, and matrix modifying proteins. Coculture with expanded cells augmented human microvascular endothelial cell survival and tubule formation under serum-starved, growth factor-reduced conditions. Expanded UCB-derived ALDHhi cells represent an alternative to autologous bone marrow as an accessible source of pro-angiogenic hematopoietic progenitor cells for the refinement of vascular regeneration-inductive therapies. Stem Cells Translational Medicine 2017;6:1607-1619.
Keyphrases
- induced apoptosis
- cell cycle arrest
- stem cells
- bone marrow
- cell proliferation
- endoplasmic reticulum stress
- mesenchymal stem cells
- endothelial cells
- oxidative stress
- type diabetes
- signaling pathway
- magnetic resonance imaging
- healthcare
- dendritic cells
- pi k akt
- cord blood
- magnetic resonance
- adipose tissue
- acute coronary syndrome
- stem cell transplantation
- peripheral artery disease