Probing the glioma micro-environment: analysis using biopsy in combination with ultra-fast cyclic immunolabeling.

The interaction between gliomas and the immune system is poorly understood and thus hindering development of effective immunotherapies for glioma patients. The immune response is highly variable during tumor development, and affected by therapies such as surgery, radiation, and chemotherapy. Currently, analysis of these local changes is difficult due to poor accessibility of the tumor and high-morbidity of sampling. In this study, we developed a model for repeat-biopsy in mice to study these local immunological changes over time. Using fine needle biopsy we were able to safely and repeatedly collect cells from intracranial tumors in mice. Ultra-fast cycling technology (FAST) was used for multi-cycle immunofluorescence of retrieved cells, and provided insights in the changing immune response over time. The combination of these techniques can be utilized to study changes in the immune response in glioma or other intracranial diseases over time, and in response to treatment within the same animal. Fine-needle biopsy and ultra-fast cycling technology techniques were developed to allow for repeat sampling and analysis of glial tumors in mice.