RT Journal Article SR Electronic T1 Peritumoral administration of IFNβ upregulated mesenchymal stem cells inhibits tumor growth in an orthotopic, immunocompetent rat glioma model JF Journal for ImmunoTherapy of Cancer JO J Immunother Cancer FD BMJ Publishing Group Ltd SP e000164 DO 10.1136/jitc-2019-000164 VO 8 IS 1 A1 Jiaji Mao A1 Minghui Cao A1 Fang Zhang A1 Jingzhong Zhang A1 Xiaohui Duan A1 Liejing Lu A1 Zehong Yang A1 Xiang Zhang A1 Wangshu Zhu A1 Qinyuan Zhang A1 Zhe Wang A1 Jun Shen YR 2020 UL http://jitc.bmj.com/content/8/1/e000164.abstract AB Background Immunotherapy with IFNβ is a promising strategy for treating malignant glioma. However, systemic administration of IFNβ is inadequate because of low intratumoral concentration and major adverse effects. This study aimed to determine whether mesenchymal stem cells (MSCs) can be used as cellular vehicles to locally deliver IFNβ for glioma therapy by using in vivo MRI tracking.Methods A recombinant lentiviral vector encoding IFNβ and ferritin heavy chain (FTH) reporter genes was constructed to transduce MSCs. The effectiveness and safety of transduction were assessed. After the IFNβ and FTH overexpressed MSCs (IFNβ-FTH-MSCs) were transplanted into intracranial orthotopic rat F98 gliomas via peritumoral, intracerebral, intratumoral or intra-arterial injection, MRI was performed to track IFNβ-FTH-MSCs and to evaluate their therapeutic effect on glioma in vivo, as validated by histologic analysis, quantitative PCR and ELISA assays.Results MSCs were efficiently and safely transduced to upregulate their IFNβ secretion and FTH expression by the constructed lentivirus. After peritumoral injection, IFNβ-FTH-MSCs appeared as hypointense signals on MRI, which gradually diminished but remained visible until 11 days. Compared with other administration routes, only peritumoral injection of IFNβ-FTH-MSCs showed a remarkable inhibition on the glioma growth. Nearly 30% of IFNβ-FTH-MSCs survived up to 11 days after peritumoral injection, while most of IFNβ-FTH-MSCs injected via other routes died within 11 days. IFNβ-FTH-MSCs grafted peritumorally secreted IFNβ persistently, leading to pronounced Batf3+ dendritic cells and CD8+ T lymphocyte infiltration within the glioma.Conclusions MSCs can be used as cellular vehicles of IFNβ to treat malignant glioma effectively via peritumoral injection.