Human mesenchymal stem cells (hMSCs) expressing truncated soluble vascular endothelial growth factor receptor (tsFlk-1) following lentiviral-mediated gene transfer inhibit growth of Burkitt's lymphoma in a murine model.
BACKGROUND
Efficient gene transfer to bone marrow derived mesenchymal stem cells (MSC) would provide an important opportunity to express potent anticancer agents in the tumour microenvironment because of their contribution to the tumour stroma.


METHODS
HIV-based lentiviral vectors were pseudotyped with four different envelope proteins; amphotropic murine leukaemia virus (ampho), murine leukaemia virus (10A1), feline endogenous virus (RD114), and the vesicular stomatitis virus glycoprotein (VSVG). These pseudotypes were examined for transduction efficiency in human bone marrow derived MSC. The effect of lentiviral expression of truncated soluble vascular endothelial growth factor decoy receptor (tsFlk-1) in MSC on growth of Raji cells was determined, both in vitro and in vivo.


RESULTS
All lentiviral vectors produced significant levels of transduction at an multiplicity of infection (MOI) of 1, those bearing the RD114 envelope glycoprotein consistently produced higher transduction levels (mean 70 +/- 6%) compared with the other pseudotyped lentiviral vectors, although there was significant inter-donor variation. Stable transgene expression was achieved after multiple rounds of transduction with VSVG-pseudotyped particles, without alteration in the differentiative capacity of transduced cells. Co-injection of MSC stably expressing tsFlk-1 with Raji Burkitt's lymphoma cells significantly impaired subcutaneous tumour growth in immunodeficient mice when compared to controls where either unmanipulated MSC or GFP-expressing MSC were used.


CONCLUSIONS
Human MSC are easily transduced by pseudotyped lentiviral particles but there is inter-donor variation in transduction efficiency. Gene-modified MSC expressing a gene of therapeutic potential can moderate growth of haematological malignancies.
Kyriakou
Chara A
CA
Department of Haematology, University College London, London, UK.
Yong
Kwee L
KL
Benjamin
Reuben
R
Pizzey
Arnold
A
Dogan
Ahmet
A
Singh
Nalini
N
Davidoff
Andrew M
AM
Nathwani
Amit C
AC
D000818:Animals; D001854:Bone Marrow Cells; D002051:Burkitt Lymphoma / Q000235:genetics* / Q000628:therapy*; D004195:Disease Models, Animal; D018014:Gene Transfer Techniques; D005822:Genetic Vectors; D006678:HIV; D006801:Humans; D016086:Lentivirus / Q000235:genetics*; D045164:Mesenchymal Stem Cell Transplantation / Q000379:methods*; D051379:Mice; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014161:Transduction, Genetic; D019076:Transgenes; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000096:biosynthesis / Q000235:genetics*; D014759:Viral Envelope Proteins
D014759:Viral Envelope Proteins; D040301:Vascular Endothelial Growth Factor Receptor-2