Engineered Hybrid Treg-Targeted Nanosomes Restrain Lung Immunosuppression by Inducing Intratumoral CD8+T Cell Immunity

Abstract

Kalliopi Domvri,1 Savvas Petanidis,2,3 Paul Zarogoulidis,4 Doxakis Anestakis,5 Charalampos Charalampidis,5 Drosos Tsavlis,6 Haidong Huang,7 Lutz Freitag,8 Wolfgang Hohenforst-Schmidt,9 Dimitris Matthaios,10 Theodora Katopodi,2 Konstantinos Porpodis3 1Pulmonary Department-Oncology Unit, “G. Papanikolaou” General Hospital, Aristotle University of Thessaloniki, Thessaloniki, 57010, Greece; 2Department of Medicine, Laboratory of Medical Biology and Genetics, Aristotle University of Thessaloniki, Thessaloniki, 54124, Greece; 3Department of Pulmonology, I.M. Sechenov First Moscow State Medical University, Moscow, 119992, Russian Federation; 4Third Department of Surgery, “AHEPA” University Hospital, Aristotle University of Thessaloniki, Thessaloniki, 55236, Greece; 5Department of Anatomy, Medical School, University of Cyprus, Nicosia, 1678, Cyprus; 6Department of Medicine, Laboratory of Experimental Physiology, Aristotle University of Thessaloniki, Thessaloniki, 54124, Greece; 7Department of Respiratory & Critical Care Medicine, Changhai Hospital, Second Military Medical University, Shanghai, 200433, People’s Republic of China; 8Department of Pulmonology, University Hospital Zurich, Zurich, 8091, Switzerland; 9Medical Clinic I, “Fuerth” Hospital, University of Erlangen, Fuerth, 91054, Germany; 10Oncology Department, General Hospital of Rodos, Rodos, 85133, GreeceCorrespondence: Savvas Petanidis, Department of Medicine, Laboratory of Medical Biology and Genetics, Aristotle University of Thessaloniki, Thessaloniki, 54124, Greece, Tel [phone], Fax [phone], Email [email protected]: Tumor immunotherapy is a key therapeutic paradigm for the treatment of several malignancies. However, in metastatic lung cancer, classical immunotherapy regimes are ineffective due to regulatory T cell (Treg)-related immunosuppression and tumor relapse.Materials: To address this issue, we designed specific biocompatible Treg-targeted nanocarriers (NCs) as a model of immune-based nanotherapy, in order to target Treg-related immunosuppression in the lung tumor microenvironment. This is achieved through the combination of Dasatinib and Epacadostat integrated into biodegradable nanosomes which can inhibit and reverse Treg-supporting immunosuppression. Flow cytometry and immunofluorescence analysis, PET/CT scan, PTT/PA imaging and the Balb/c tumor model were used to explore the anti-tumor effect of Treg-targeted NCs both in vitro and in vivo.Results: Findings reveal that NC treatment triggered substantial tumor cell apoptosis and drastically decreased tumor volume followed by downregulation of Ki-67 antigen expression, respectively. Drug circulation time was also increased as shown by biodistribution analysis accompanied by greater accumulation in lung and peripheral tissues. Intratumoral Th1 cytokines’ expression was also increased, especially TNF-A, IL-12 by 42%, and IL-6 by 18% compared to PBS treatment. In addition, the presence of mature CD80+/CD86+dendritic cells (DCs) revealed T cell enrichment and a decline in MDSC infiltration and myeloid subsets. Interestingly, a significant decline of Gr/CD11b myeloid cell population in blood and tissue samples was also observed. This immune activation can be attributed to the enhanced PTT efficiency and tumor targeting ability of the nanospheres which under near infrared (NIR) exposure can prompt highly efficient tumor ablation. We also demonstrated their therapeutic efficacy against 4T1 metastatic breast cancer model. Additionally, the photothermal therapy in combination with PD-L1 checkpoint blockade therapy exerted long-term tumor control over both primary and distant tumors.Discussion: Overall, our findings present a novel nano-enabled platform for the inhibition of Treg-dependent immunosuppression in NSCLC and provide a novel nanotherapeutic strategy for the treatment of metastatic neoplasia.Keywords: Tregs, nanosomes, metastasis, immunosuppression, T cells

Keywords

• tregs
• nanosomes
• metastasis
• immunosuppression
• t cells.