title: Biodegradable ECM-coated PCL microcarriers support scalable human early MSC expansion and in vivo bone formation.
abstract: Human mesenchymal stromal cells or marrow stromal cells (MSCs) are of great interest for bone healing due to their multi-potency and trophic effects. However, traditional MSC expansion methods using 2-dimensional monolayer (MNL) flasks or cell stacks are limited by labor-intensive handling, lack of scalability, the need for enzymatic cell harvesting and the need for attachment to a scaffold before in vivo delivery. Here, we present a biodegradable microcarrier and MSC bioprocessing system that may overcome the abovementioned challenges.
  
  
  
  We cultured human early MSCs (heMSCs) on biodegradable polycaprolactone microcarriers (PCL MCs) coated with extracellular matrix (ECM) and evaluated the in vitro osteogenic differentiation and in vivo bone formation capacity of ECM-coated PCL MC-bound heMSCs compared with conventional MNL-cultured cells.
  
  
  
  We found that heMSCs proliferate well on PCL MCs coated with a fibronectin, poly-l-lysine, and fibronectin (FN+PLL+FN) coating (cPCL MCs). During in vitro osteogenic induction, heMSCs cultured on cPCL MCs displayed a 68% increase in specific calcium deposition compared with cultures on MNL. In a mouse ectopic mineralization model, bone mass was equivalent for MNL-expanded and cPCL MC-bound heMSC implants but higher in both cases when compared with cell-free cPCL MC implants at 16 weeks post-implantation. In summary, compared with MNL cultures, biodegradable MC MSC cultures provide the benefits of large-scale expansion of cells and can be delivered in vivo, thereby eliminating the need for cell harvesting and use of scaffolds for cell delivery. These results highlight the promise of delivering heMSCs cultured on cPCL MCs for bone applications.
authors: Stem Cell Group, Bioprocessing Technology Institute, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore. Electronic address: asha_shekaran@bti.a-star.edu.sg.
authors: Asha
authors: A
authors: Shekaran
authors: Stem Cell Group, Bioprocessing Technology Institute, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore.
authors: Alan
authors: A
authors: Lam
authors: Stem Cell Group, Bioprocessing Technology Institute, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore.
authors: Eileen
authors: E
authors: Sim
authors: Stem Cell Group, Bioprocessing Technology Institute, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore.
authors: Lee
authors: L
authors: Jialing
authors: Patterning and Fabrication Capability Group, Institute for Materials Research & Engineering, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore.
authors: Li
authors: L
authors: Jian
authors: Patterning and Fabrication Capability Group, Institute for Materials Research & Engineering, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore.
authors: Jessica Toh Pei
authors: JT
authors: Wen
authors: Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Cancer & Stem Cell Biology Program, Duke-NUS Graduate Medical School, Singapore; Department of Reproductive Medicine, KK Women's and Children's Hospital, Singapore, Singapore.
authors: Jerry Kok Yen
authors: JK
authors: Chan
authors: Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
authors: Mahesh
authors: M
authors: Choolani
authors: Stem Cell Group, Bioprocessing Technology Institute, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore.
authors: Shaul
authors: S
authors: Reuveny
authors: Patterning and Fabrication Capability Group, Institute for Materials Research & Engineering, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore.
authors: William
authors: W
authors: Birch
authors: Stem Cell Group, Bioprocessing Technology Institute, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore. Electronic address: steve_oh@bti.a-star.edu.sg.
authors: Steve
authors: S
authors: Oh
mesh_terms: D020341:Absorbable Implants; D000818:Animals; D001861:Bone Regeneration / Q000187:drug effects; D018929:Cell Culture Techniques / Q000295:instrumentation / Q000379:methods; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D005109:Extracellular Matrix / Q000737:chemistry*; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D051379:Mice; D055616:Microtechnology; D008904:Miniaturization / Q000295:instrumentation / Q000379:methods; D010012:Osteogenesis / Q000187:drug effects / Q000502:physiology*; D011091:Polyesters / Q000737:chemistry* / Q000494:pharmacology; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D011091:Polyesters; C016240:polycaprolactone
keywords: Human mesenchymal stromal cells; PCL; bone formation; microcarriers; osteogenic