Myxoma Virus Therapy of Malignant Gliomas in Murine Syngeneic Models: Translating Barriers to Therapy

atmire.migration.oldid1334
dc.contributor.advisorForsyth, Peter
dc.contributor.advisorYong, V. Wee
dc.contributor.authorZemp, Franz Joseph
dc.date.accessioned2013-09-13T21:03:10Z
dc.date.available2013-11-12T08:00:13Z
dc.date.issued2013-09-13
dc.date.submitted2013en
dc.description.abstractHigh grade glioma has an almost universally fatal outcome. Failure of current treatment modalities has prompted the investigation into non-traditional therapies. Oncolytic virus therapy entails the use of replication competent viruses that selectively infect, replicate and kill cancer cells. This multi-modal therapy can function to directly kill cancer cells, stimulate anti-tumour immune responses, and be engineered to express additional anti-tumour activities. Despite promising preclinical studies in xenograft models, clinical trials have demonstrated no overwhelming treatment responses. Interestingly, syngeneic glioma models have shown results more typical of what was seen in the clinic. This study was undertaken to identify the potential immune-effectors mediating Myxoma virus (MYXV) clearance in immunocompetent mouse models. MYXV is a rabbit-specific poxvirus that has oncolytic properties in cancer cell lines, having previously been shown to ‘cure’ human xenograft models. We found that syngeneic murine glioma lines derived from Nf1+/-Trp53+/- mice formed aggressive, gliosarcoma-like tumours in the brains of C57Bl/6 mice, but MYXV administration resulted in a very transient infection and no treatment efficacy. Further, a new syngeneic glioma model was created through culturing spontaneous gliomas from these mice as neurospheres. These lines displayed stem cell markers and produce highly invasive gliomas when grafted into the brains of immunocompetent C57Bl/6 mice. We hypothesized that Type-I interferon (IFNα/β), could be playing a role in this resistance. However, it was found that MYXV treatment did not elicit an IFNα/β response in these glioma lines in vitro or in vivo. Further, engineered ablation of IFNα/β signalling in the glioma in vivo had no change in treatment outcome. Immunophenotyping the glioma microenvironment found these gliomas were heavily infiltrated with microglia and macrophages, just as has been shown in human patients. Ablation of tumour-resident macrophages, not treatment-recruited macrophages, resulted in a significant increase in viral infection in the tumours that resulted in a mild survival advantage; however, the virus was still rapidly cleared in these animals. NK and T cell populations were also recruited to the tumour. Interestingly, ablation of both these populations, but not either one alone, resulted in a robust, durable infection in the tumour that resulted in survival benefit.en_US
dc.identifier.citationZemp, F. J. (2013). Myxoma Virus Therapy of Malignant Gliomas in Murine Syngeneic Models: Translating Barriers to Therapy (Doctoral thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/27049en_US
dc.identifier.doihttp://dx.doi.org/10.11575/PRISM/27049
dc.identifier.urihttp://hdl.handle.net/11023/967
dc.language.isoeng
dc.publisher.facultyGraduate Studies
dc.publisher.institutionUniversity of Calgaryen
dc.publisher.placeCalgaryen
dc.rightsUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.
dc.subjectVirology
dc.subjectImmunology
dc.subjectOncology
dc.subject.classificationOncolytic virusen_US
dc.subject.classificationgliomaen_US
dc.subject.classificationMouse modelsen_US
dc.titleMyxoma Virus Therapy of Malignant Gliomas in Murine Syngeneic Models: Translating Barriers to Therapy
dc.typedoctoral thesis
thesis.degree.disciplineMedical Science
thesis.degree.grantorUniversity of Calgary
thesis.degree.nameDoctor of Philosophy (PhD)
ucalgary.item.requestcopytrue
Files
Original bundle
Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
ucalgary_2013_zemp_franz.pdf
Size:
9.19 MB
Format:
Adobe Portable Document Format
License bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
license.txt
Size:
2.65 KB
Format:
Item-specific license agreed upon to submission
Description: