Title: Yield optimisation and molecular characterisation of uncultured CD271⁺ mesenchymal stem cells in the reamer irrigator aspirator waste bag

Author: SM Churchman, D Kouroupis, SA Boxall, T Roshdy, HB Tan, D McGonagle, PV Giannoudis, EA Jones

Address: Academic Department of Trauma & Orthopaedic Surgery, A Floor, Clarendon Wing, Leeds General Infirmary, Great George Street, Leeds LS1 3EX, UK

E-mail: pgiannoudi at aol.com

Key Words: Multipotential stromal cell; bone regeneration; long bone; gene expression; Reamer/Irrigator/Aspirator.

Publication date: December 13th 2013

Abstract: Bone reconstruction requires the use of autografts from patients’ iliac crest (IC); for large-volume defects bone void fillers and autologous mesenchymal stem cells (MSCs) are often added. The Reamer/Irrigator/Aspirator (RIA) device provides the means of harvesting large amounts of autograft and additionally yields a waste bag containing MSCs, which is currently discarded. The aim of this study was to enumerate and characterise native MSCs from RIA waste bag and compare them to ‘gold-standard’ donor-matched MSCs from IC bone marrow (BM). IC-BM from age matched trauma patients was used as control.

In RIA waste bags the median MSC yield established using a colony-forming fibroblast assay was 314333 (range 5 x 104-1.4 x 106), equivalent to approximately one litre of IC-BM aspirate. CD271⁺ cells were present at high levels in RIA waste bags, had MSC surface phenotype (CD90⁺CD73⁺CD105⁺CD34>sup>-CD61^-CD19^-CD31^-CD33^-) and expressed genes associated with multipotentiality, osteogenesis, adipogenesis and angiogenic support. RIA- CD271⁺ MSCs were transcriptionally similar to donor-matched IC-CD271⁺ MSCs (76 % transcripts); with the majority of bone-related and Wnt pathway molecules being expressed at comparable levels. Lower-level expression of MCAM/CD146 and 5/13 hypoxia-related molecules was found in RIA-CD271⁺ MSCs, potentially reflecting their native residence in a more hypoxic environment of the endosteum and bone cortex.

These data suggest that long bones contain very large numbers of MSCs, transcriptionally-similar to IC-BM MSCs; they can be procured by reaming using the RIA device and used, following concentration, as autologous and potentially allogeneic bone repair therapy.

Article download: Pages 252-262 (PDF file)
DOI: 10.22203/eCM.v026a18