title: Engraftment Outcomes after HPC Co-Culture with Mesenchymal Stromal Cells and Osteoblasts.
abstract: Haematopoietic stem cell (HSC) transplantation is an established cell-based therapy for a number of haematological diseases. To enhance this therapy, there is considerable interest in expanding HSCs in artificial niches prior to transplantation. This study compared murine HSC expansion supported through co-culture on monolayers of either undifferentiated mesenchymal stromal cells (MSCs) or osteoblasts. Sorted Lineage(-) Sca-1(+) c-kit(+) (LSK) haematopoietic stem/progenitor cells (HPC) demonstrated proliferative capacity on both stromal monolayers with the greatest expansion of LSK shown in cultures supported by osteoblast monolayers. After transplantation, both types of bulk-expanded cultures were capable of engrafting and repopulating lethally irradiated primary and secondary murine recipients. LSKs co-cultured on MSCs showed comparable, but not superior, reconstitution ability to that of freshly isolated LSKs. Surprisingly, however, osteoblast co-cultured LSKs showed significantly poorer haematopoietic reconstitution compared to LSKs co-cultured on MSCs, likely due to a delay in short-term reconstitution. We demonstrated that stromal monolayers can be used to maintain, but not expand, functional HSCs without a need for additional haematopoietic growth factors. We also demonstrated that despite apparently superior in vitro performance, co-injection of bulk cultures of osteoblasts and LSKs in vivo was detrimental to recipient survival and should be avoided in translation to clinical practice.
authors.affiliation: Stem Cell and Regenerative Medicine Group, Biological Therapies Program, Mater Research Institute, University of Queensland, TRI Building, 37 Kent Street, Woolloongabba, Queensland 4102, Australia. mattmaccook@gmail.com.|School of Medicine, University of Queensland, 288 Herston Road, Herston, Queensland 4006, Australia. mattmaccook@gmail.com.
authors.forename: Matthew M
authors.initials: MM
authors.lastname: Cook
authors.affiliation: Stem Cell and Regenerative Medicine Group, Biological Therapies Program, Mater Research Institute, University of Queensland, TRI Building, 37 Kent Street, Woolloongabba, Queensland 4102, Australia. michael.doran@qut.edu.au.|Institute of Health and Biomedical Innovation, Queensland University of Technology, 60 Musk Avenue, Kelvin Grove Urban Village, Kelvin Grove, Queensland 4059, Australia. michael.doran@qut.edu.au.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Doran
authors.affiliation: Stem Cell and Regenerative Medicine Group, Biological Therapies Program, Mater Research Institute, University of Queensland, TRI Building, 37 Kent Street, Woolloongabba, Queensland 4102, Australia. katekollar@gmail.com.
authors.forename: Katarina
authors.initials: K
authors.lastname: Kollar
authors.affiliation: Stem Cell and Cancer Group, Biological Therapies Program, Mater Medical Research Institute, Level 3, Aubigny Place, Raymond Terrace, South Brisbane, Queensland 4101, Australia. vbarbier@mmri.mater.org.au.
authors.forename: Valerie
authors.initials: V
authors.lastname: Barbier
authors.affiliation: Stem Cell and Cancer Group, Biological Therapies Program, Mater Medical Research Institute, Level 3, Aubigny Place, Raymond Terrace, South Brisbane, Queensland 4101, Australia. iwinkler@mmri.mater.org.au.
authors.forename: Ingrid G
authors.initials: IG
authors.lastname: Winkler
authors.affiliation: School of Medicine, University of Queensland, 288 Herston Road, Herston, Queensland 4006, Australia. jplevesque@mmri.mater.org.au.|Stem Cell and Cancer Group, Biological Therapies Program, Mater Medical Research Institute, Level 3, Aubigny Place, Raymond Terrace, South Brisbane, Queensland 4101, Australia. jplevesque@mmri.mater.org.au.
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Levesque
authors.affiliation: Stem Cell and Regenerative Medicine Group, Biological Therapies Program, Mater Research Institute, University of Queensland, TRI Building, 37 Kent Street, Woolloongabba, Queensland 4102, Australia. gpbrooke@gmail.com.
authors.forename: Gary
authors.initials: G
authors.lastname: Brooke
authors.affiliation: Stem Cell and Regenerative Medicine Group, Biological Therapies Program, Mater Research Institute, University of Queensland, TRI Building, 37 Kent Street, Woolloongabba, Queensland 4102, Australia. m.atkinson1@uq.edu.au.|School of Medicine, University of Queensland, 288 Herston Road, Herston, Queensland 4006, Australia. m.atkinson1@uq.edu.au.
authors.forename: Kerry
authors.initials: K
authors.lastname: Atkinson
keywords: ex vivo expansion; haematopoietic reconstitution; haematopoietic stem cells; mesenchymal stromal cells; osteoblasts