Plerixafor

Blocking the C-X-C motif chemokine ligand-12/C-X-C motif chemokine receptor-4 (CXCL12/CXCR4) signal offers the potential to induce immunogenic cell death (ICD) and enhance immunotherapy of glioblastoma (GBM). However, traditional intracellular targeted delivery strategies and adenosine-mediated tumor immunosuppression limit its therapeutic efficacy. Herein, we present an acidity-triggered self-assembly nanoplatform based on bioorthogonal reaction to potentiate GBM immunotherapy through dual regulation of metabolism and immune pathways. AMD3100 (CXCR4 antagonist) and CPI-444 (adenosine 2A receptor inhibitor) were formulated into micelles, denoted as AMD@iNP_DBCO and CPI@iNP_N3, respectively. Upon administration, the pH-sensitive poly(2-azepane ethyl methacrylate) group of AMD@iNP_DBCO responds to the acidic tumor microenvironment, exposing the DBCO moiety, resulting in highly efficient bioorthogonal reaction with azide group on CPI@iNP_N3 to form large-sized aggregates, ensuring extracellular drug release. The combination of AMD3100 and CPI-444 contributes to ICD induction, dendritic cell maturation, and immunosuppressive milieu alleviation by reducing tumor-associated macrophages, myeloid-derived suppressor cells, and regulatory T cells, leading to a robust antitumor response, thereby significantly prolonging survival in orthotopic GBM-bearing mice. Furthermore, the nanoplatform remarkably amplifies immuno-radiotherapy by potently evoking cytotoxic CD8⁺ T cell priming, and synergized with immune checkpoint blockade by delaying CD8⁺ T cell exhaustion. Our work highlights the potential of the in situ assembly nanoplatform tailored for delivery of extracellular-targeted therapeutic agents for boosting GBM immunotherapy.

We developed an in vivo hematopoietic stem cell (HSC) gene therapy approach consisting of HSC mobilization and intravenous injection of helper dependent adenovirus (HDAd) vectors. While we have demonstrated safety and efficacy of the in vivo approach in CD46-transgenic mice and rhesus macaques, studies in mice with a humanized hematopoietic system could facilitate its potential clinical translation for the treatment of hemoglobinopathies and HIV. Using mild myelo-conditioning in NSGW41 mice and cryopreserved human CD34⁺ cells from healthy donors we achieved ∼10% human chimerism in peripheral blood. Engrafted primitive human CD45⁺/CD34⁺/CD90⁺-HSCs efficiently mobilized by different approaches involving AMD3100 in combination with granulocyte colony-stimulating factor G-CSF, truncated Groβ (tGroβ), or WU106/tGroβ. At the peak of mobilization, integrating HDAd-GFP vectors were injected intravenously followed by O⁶BG/BCNU in vivo selection. Long-term stable GFP expression was shown for HDAd5/35 and the new vector platforms HDAd6/3 and HDAd5/35_lam, a fiber/penton-modified vector. Two months post transduction, GFP marking in the periphery were 22.38% (8.17%), 41.12% (10.62%), and 32.15% (4.49%) for HDAd5/35, HDAd6/3, and HDAd5/35_lam, respectively. GFP levels in bone marrow were 33.53% (8.96%), 53.51% (6.95%), and 33.29% (5.21%) and in spleen 32.6% (9.25%), 33.75% (5.47%), and 20.79% (6.15%). Our study describes a new animal model for in vivo HSC transduction with HDAds, with implications for studies with other vectors.