title: Expanded Hematopoietic Progenitor Cells Reselected for High Aldehyde Dehydrogenase Activity Demonstrate Islet Regenerative Functions.
abstract: Human umbilical cord blood (UCB) hematopoietic progenitor cells (HPC) purified for high aldehyde dehydrogenase activity (ALDH(hi) ) stimulate islet regeneration after transplantation into mice with streptozotocin-induced β cell deletion. However, ALDH(hi) cells represent a rare progenitor subset and widespread use of UCB ALDH(hi) cells to stimulate islet regeneration will require progenitor cell expansion without loss of islet regenerative functions. Here we demonstrate that prospectively purified UCB ALDH(hi) cells expand efficiently under serum-free, xeno-free conditions with minimal growth factor supplementation. Consistent with the concept that ALDH-activity is decreased as progenitor cells differentiate, kinetic analyses over 9 days revealed the frequency of ALDH(hi) cells diminished as culture time progressed such that total ALDH(hi) cell number was maximal (increased 3-fold) at day 6. Subsequently, day 6 expanded cells (bulk cells) were sorted after culture to reselect differentiated progeny with low ALDH-activity (ALDH(lo) subset) from less differentiated progeny with high ALDH-activity (ALDH(hi) subset). The ALDH(hi) subset retained primitive cell surface marker coexpression (32.0% ± 7.0% CD34(+) /CD38(-) cells, 37.0% ± 6.9% CD34(+) /CD133(+) cells), and demonstrated increased hematopoietic colony forming cell function compared with the ALDH(lo) subset. Notably, bulk cells or ALDH(lo) cells did not possess the functional capacity to lower hyperglycemia after transplantation into streptozotocin-treated NOD/SCID mice. However, transplantation of the repurified ALDH(hi) subset significantly reduced hyperglycemia, improved glucose tolerance, and increased islet-associated cell proliferation and capillary formation. Thus, expansion and delivery of reselected UCB cells that retain high ALDH-activity after short-term culture represents an improved strategy for the development of cellular therapies to enhance islet regeneration in situ.
authors.affiliation: Krembil Centre for Stem Cell Biology, Molecular Medicine Research Group, Robarts Research Institute, London, Ontario, Canada.|Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada.
authors.forename: Ayesh K
authors.initials: AK
authors.lastname: Seneviratne
authors.affiliation: Krembil Centre for Stem Cell Biology, Molecular Medicine Research Group, Robarts Research Institute, London, Ontario, Canada.|Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada.
authors.forename: Gillian I
authors.initials: GI
authors.lastname: Bell
authors.affiliation: Krembil Centre for Stem Cell Biology, Molecular Medicine Research Group, Robarts Research Institute, London, Ontario, Canada.|Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada.
authors.forename: Stephen E
authors.initials: SE
authors.lastname: Sherman
authors.affiliation: Krembil Centre for Stem Cell Biology, Molecular Medicine Research Group, Robarts Research Institute, London, Ontario, Canada.|Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada.
authors.forename: Tyler T
authors.initials: TT
authors.lastname: Cooper
authors.affiliation: Krembil Centre for Stem Cell Biology, Molecular Medicine Research Group, Robarts Research Institute, London, Ontario, Canada.|Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada.
authors.forename: David M
authors.initials: DM
authors.lastname: Putman
authors.affiliation: Krembil Centre for Stem Cell Biology, Molecular Medicine Research Group, Robarts Research Institute, London, Ontario, Canada.|Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada.
authors.forename: David A
authors.initials: DA
authors.lastname: Hess
mesh_terms: D000444:Aldehyde Dehydrogenase / Q000096:biosynthesis* / Q000235:genetics; D000818:Animals; D002454:Cell Differentiation / Q000235:genetics; D049109:Cell Proliferation / Q000235:genetics; D002469:Cell Separation; D064987:Cell- and Tissue-Based Therapy; D036101:Cord Blood Stem Cell Transplantation; D003921:Diabetes Mellitus, Experimental / Q000473:pathology / Q000628:therapy*; D005312:Fetal Blood / Q000166:cytology; D018380:Hematopoietic Stem Cell Transplantation; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000378:metabolism; D006801:Humans; D007515:Islets of Langerhans / Q000254:growth & development* / Q000378:metabolism / Q000473:pathology; D051379:Mice; D012038:Regeneration
chemical_list: D000444:Aldehyde Dehydrogenase
keywords: Aldehyde dehydrogenase; Diabetes; Hematopoietic progenitor cells; Islet regeneration; Transplantation; Umbilical cord blood