ABSTRACT
Despite the important breakthroughs of immune checkpoint inhibitors in recent years, the objective response rates remain limited. Here, we synthesize programmed cell death protein-1 (PD-1) antibody-iRGD cyclic peptide conjugate (αPD-1-(iRGD)2) through glycoengineering methods. In addition to enhancing tissue penetration, αPD-1-(iRGD)2 simultaneously engages tumor cells and PD-1+ T cells via dual targeting, thus mediating tumor-specific T cell activation and proliferation with mild effects on non-specific T cells. In multiple syngeneic mouse models, αPD-1-(iRGD)2 effectively reduces tumor growth with satisfactory biosafety. Moreover, results of flow cytometry and single-cell RNA-seq reveal that αPD-1-(iRGD)2 remodels the tumor microenvironment and expands a population of "better effector" CD8+ tumor infiltrating T cells expressing stem- and memory-associated genes, including Tcf7, Il7r, Lef1, and Bach2. Conclusively, αPD-1-(iRGD)2 is a promising antibody conjugate therapeutic beyond antibody-drug conjugate for cancer immunotherapy.
Subject(s)
Programmed Cell Death 1 Receptor , Tumor Microenvironment , Animals , Programmed Cell Death 1 Receptor/immunology , Programmed Cell Death 1 Receptor/antagonists & inhibitors , Mice , Tumor Microenvironment/immunology , Tumor Microenvironment/drug effects , Humans , Cell Line, Tumor , T-Lymphocytes/immunology , T-Lymphocytes/drug effects , Mice, Inbred C57BL , Oligopeptides/chemistry , Oligopeptides/pharmacology , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/drug effects , Immunoconjugates/pharmacology , Immunoconjugates/chemistry , Female , Lymphocyte Activation/drug effects , Lymphocyte Activation/immunology , Lymphocytes, Tumor-Infiltrating/immunology , Lymphocytes, Tumor-Infiltrating/drug effects , Immune Checkpoint Inhibitors/pharmacologyABSTRACT
INTRODUCTION: Multiple studies show that transfusion independence (TI) in myelodysplastic syndrome (MDS) has a positive impact on overall survival (OS). To assess this, a systematic review and meta-analysis of the association between TI and OS in patients with MDS was conducted (PROSPERO ID: CRD42014007264). METHODS: Comprehensive searches of 5 key bibliographic databases were conducted and supplemented with additional search techniques. Included were studies that had recruited adults aged >18 years with MDS and had examined the impact of transfusion status on OS. RESULTS: Fifty-five studies (89 citations) were included. The vast majority reported a statistically significant hazard ratio (HR) for OS in favor of TI patients or in patients who acquired TI after treatment. A random-effects meta-analysis was conducted. Patients classed as TI at baseline showed a 59% decrease in the risk of death compared with transfusion-dependent (TD) patients [HR 0.41; 95% credible interval (CrI) 0.29-0.56], and this effect did not appear to interact significantly with illness severity (interaction coefficient HR 1.38; 95% CrI 0.62-3.41). A meta-analysis of studies where patients acquired TI was not possible, but those studies consistently reported a survival benefit for those who acquired TI. CONCLUSION: The findings revealed a 59% pooled reduction in mortality among TI patients when compared with TD patients.
