RESUMO
Glioblastoma multiforme (GBM) is the most common and aggressive form of primary brain cancer, for which effective therapies are urgently needed. Chimeric antigen receptor (CAR)-based immunotherapy represents a promising therapeutic approach, but it is often impeded by highly immunosuppressive tumor microenvironments (TME). Here, in an immunocompetent, orthotopic GBM mouse model, we show that CAR-T cells targeting tumor-specific epidermal growth factor receptor variant III (EGFRvIII) alone fail to control fully established tumors but, when combined with a single, locally delivered dose of IL-12, achieve durable anti-tumor responses. IL-12 not only boosts cytotoxicity of CAR-T cells, but also reshapes the TME, driving increased infiltration of proinflammatory CD4+ T cells, decreased numbers of regulatory T cells (Treg), and activation of the myeloid compartment. Importantly, the immunotherapy-enabling benefits of IL-12 are achieved with minimal systemic effects. Our findings thus show that local delivery of IL-12 may be an effective adjuvant for CAR-T cell therapy for GBM.
Assuntos
Neoplasias Encefálicas/terapia , Glioblastoma/terapia , Imunoconjugados/administração & dosagem , Imunoterapia Adotiva/métodos , Interleucina-12/administração & dosagem , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/imunologia , Encéfalo/patologia , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral/transplante , Modelos Animais de Doenças , Receptores ErbB/imunologia , Feminino , Glioblastoma/diagnóstico por imagem , Glioblastoma/imunologia , Glioblastoma/patologia , Humanos , Imunoconjugados/imunologia , Fragmentos Fc das Imunoglobulinas/administração & dosagem , Fragmentos Fc das Imunoglobulinas/imunologia , Injeções Intralesionais/métodos , Interleucina-12/imunologia , Imagem por Ressonância Magnética Intervencionista , Camundongos , Receptores de Antígenos Quiméricos/imunologia , Anticorpos de Cadeia Única/administração & dosagem , Anticorpos de Cadeia Única/imunologia , Linfócitos T Reguladores/imunologia , Microambiente Tumoral/imunologiaRESUMO
Bioluminescence imaging (BLI) is ubiquitous in scientific research for the sensitive tracking of biological processes in small animal models. However, due to the attenuation of visible light by tissue, and the limited set of near-infrared bioluminescent enzymes, BLI is largely restricted to monitoring single processes in vivo. Here we show, that by combining stabilised colour mutants of firefly luciferase (FLuc) with the luciferin (LH2) analogue infraluciferin (iLH2), near-infrared dual BLI can be achieved in vivo. The X-ray crystal structure of FLuc with a high-energy intermediate analogue, 5'-O-[N-(dehydroinfraluciferyl)sulfamoyl] adenosine (iDLSA) provides insight into the FLuc-iLH2 reaction leading to near-infrared light emission. The spectral characterisation and unmixing validation studies reported here established that iLH2 is superior to LH2 for the spectral unmixing of bioluminescent signals in vivo; which led to this novel near-infrared dual BLI system being applied to monitor both tumour burden and CAR T cell therapy within a systemically induced mouse tumour model.