3D biodistribution of pre-treated MSC in mouse model of liver disease using CryoViz™

Abstract ‘MERLIN’ (Mesenchymal stem cells to reduce liver inflammation) is an EU FP7-funded project in which BioInVision, Inc. (Cleveland, OH, USA) is partnering with EU establishments that are developing MSC cellular therapy for primary sclerosing cholangitis (PSC), a type of liver disease. MSC have low immunogenicity and possess promising immune modulatory and regulatory capabilities, making them suitable candidates for treating PSC. In MERLIN project, BioInVision’s CryoViz™ cryo-imaging system is being used to study MSC survival under various pre-treatments in a CCL4 liver injury whole mouse model. CryoViz™ consists of a fully automated system for sectioning and tiled microscopic imaging of tissues, providing anatomical brightfield and molecular fluorescence with single cell sensitivity. Umbilical cord-derived MSC (UCMSC) were pre-treated for three days in the presence of pro-/anti-inflammatory cytokines, vitamins and serum-deprivation after which assays were performed to examine their immunogenicity, phenotype, and susceptibility to NK lysis. Subsequently, whole mice intravenously injected with the different pre-treated MSC [no treatment, IFNγ, IFNβ, TGFβ, Starvation, VitB6, (Starvation+VitB6), RA] were frozen and cryo-imaged. Global biodistribution results from CryoViz™ indicate that pretreatment had an effect on cell survival. Localized biodistribution showed preferential distribution in some organs such as the lung and the liver. The cryo-imaging study has revealed that MSC could be optimized to become less immunogenic and more immunomodulatory, which is an important step towards further development of MSC for cellular therapy.