Ex vivo expansion of haematopoietic stem/progenitor cells from human umbilical cord blood on acellular scaffolds prepared from MS-5 stromal cell line Abhilasha Tiwari 1,5 , Melinda L. Tursky 2,3 , Dolly Mushahary 1 , Samiksha Wasnik 1,5 , Fiona M. Collier 2 , Kantipudi Suma 4 , Mark A. Kirkland 2,5 and Gopal Pande 1 * 1 CSIR Centre for Cellular and Molecular Biology (CCMB), Hyderabad, India 2 Barwon Biomedical Research (BBR), Geelong Hospital, VIC, Australia 3 Lowy Cancer Research Centre, University of New South Wales, NSW, Australia 4 Sridevi Nursing Home, 12-11-253, Warasiguda, Secunderabad, India 5 Deakin University, Waurn Ponds, Geelong, VIC, Australia Abstract Lineage-specific expansion of haematopoietic stem/progenitor cells (HSPCs) from human umbilical cord blood (UCB) is desirable because of their several applications in translational medicine, e.g. treatment of cancer, bone marrow failure and immunodeficiencies. The current methods for HSPC expansion use either cellular feeder layers and/or soluble growth factors and selected matrix components coated on different surfaces. The use of cell-free extracellular matrices from bone marrow cells for this purpose has not previously been reported. We have prepared insoluble, cell-free matrices from a murine bone marrow stromal cell line (MS-5) grown under four different conditions, i.e. in presence or absence of osteogenic medium, each incubated under 5% and 20% O 2 tensions. These acellular matrices were used as biological scaffolds for the lineage-specific expansion of magnetically sorted CD34 + cells and the results were evaluated by flow cytometry and colony-forming assays. We could get up to 80-fold expansion of some HSPCs on one of the matrices and our results indicated that oxygen tension played a significant role in determining the expansion capacity of the matrices. A comparative proteomic analysis of the matrices indicated differential expression of proteins, such as aldehyde dehydrogenase and gelsolin, which have previously been identified as playing a role in HSPC maintenance and expansion. Our approach may be of value in identifying factors relevant to tissue engineering-based ex vivo HSPC expansion, and it may also provide insights into the constitution of the niche in which these cells reside in the bone marrow. Copyright © 2012 John Wiley & Sons, Ltd. Received 23 August 2011; Revised 18 November 2011; Accepted 16 January 2012 Supporting information may be found in the online version of this article. Keywords haematopoietic niche; acellular biological scaffold; extracellular matrix; umbilical cord blood; stem cell expansion; proteomics 1. Introduction Haematopoietic stem and progenitor cells (HSPCs) are inherently migratory and they come in contact with several niches through the course of their development (Jones and Wagers, 2008). The interaction of HSPCs with their niches regulates their differentiation into more com- mitted lineages, such as the common lymphoid progeni- tors (CLPs) and the common myeloid progenitors (CMPs) (Orkin and Zon, 2008). Four major components of stem cell niches are known to control the growth and differen- tiation of HSPCs: (a) extracellular signals emanating from soluble or insoluble growth factors; (b) specific cell–cell interactions between HSPCs and other supporting cells within the niche; (c) signals generated by the diffusible and non-diffusible proteins, glycoproteins and proteogly- cans present in the extracellular matrix (ECM) of the *Correspondence to: G. Pande, CSIR Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500007, India. E-mail: gpande@ccmb.res.in Copyright © 2012 John Wiley & Sons, Ltd. JOURNAL OF TISSUE ENGINEERING AND REGENERATIVE MEDICINE RESEARCH ARTICLE J Tissue Eng Regen Med (2012) Published online in Wiley Online Library (wileyonlinelibrary.com) DOI: 10.1002/term.1479