Molecular Therapy最新文献

Although CAR T-cell therapy is increasingly used to treat relapsed B-cell acute lymphoblastic leukemia (ALL), 20-30% of patients do not respond, and few clinical predictors of response have been established, especially in the pediatric population. A deeper analysis of CAR T-cell infusion products, along with the apheresis product used as the starting material for CAR T-cell manufacturing, provides valuable insights for predicting clinical outcomes. We analyzed infusion products and CD4/8-selected T-cell starting materials from pediatric and young adult patients on a single-center study with relapsed/refractory B-cell ALL who were undergoing treatment with CD22 CAR T-cells and evaluated differences between T-cells from responders and non-responders (NCT023215612). We found that CAR T-cells from non-responders had a more differentiated T-cell phenotype and overexpressed genes associated with cytotoxicity and exhaustion compared to those of responders. Furthermore, we found that these differences could be tracked back to the apheresis materials prior to CAR T-cell manufacturing. Using flow cytometry-based immunophenotypic markers, we developed a scoring system that distinguished non-responders based on T-cell phenotype at the time of apheresis. These findings can help inform outcomes for patients and providers as well as provide insights into targeted manufacturing changes to optimize CAR T-cell efficacy.

mRNA-based therapeutics delivered via lipid nanoparticles (LNP-mRNA) hold great promise for treating diverse diseases. However, further improvements are needed to refine outcomes in non-vaccine, extrahepatic applications, such as minimizing the mononuclear phagocyte system's (MPS)' rapid clearance and off-target toxicity in undesired tissues. We propose modifying LNP surfaces with the phagocytic cell "don't eat me" signal, CD47, in combination with our previously established antibody-based targeted LNP (tLNP) to create a CD47/tLNP platform with reduced phagocytic clearance and off-target effects, and improved efficiency for cell-specific delivery. We showed that CD47 modification decreased macrophage and hepatic uptake both in vitro and in vivo. Combining CD47 modification with antibodies targeting endothelial cells, T cells, or hematopoietic stem cells (HSCs) increased targeting efficiency up to 3-fold compared to tLNP alone. Enhanced targeting of CD47/tLNP to HSCs with reduced off-targeting enabled the delivery of pro-apoptotic mRNA for HSC depletion as a preconditioning strategy prior to bone marrow transplant. Additionally, CD47-modified LNPs showed diminished inflammatory effects on hepatic tissue and an altered protein corona. Our CD47/tLNP-mRNA platform, with its reduced phagocytic clearance, mitigated inflammatory effects, and enhanced targeted delivery, should further facilitate the development of in vivo mRNA therapeutics.

The skin is the largest organ of the body and forms and serves as the barrier for preventing external material from accessing and damaging internal organs. As the outward interface to the environment, it is accessible for the application of therapeutic agents and cellular and gene therapy represent attractive and promising options to treat severe genetic conditions for which palliation has long been the main stay. However, because of its barrier function, transit across and to the sub-dermal compartment can be challenging. This commentary examines the current approaches of cell and gene therapies for genetic skin disorders. We write this from a local and systemic 'outside and inside' perspective. Delivery from the outside encompasses topical, intradermal, and transdermal strategies for cell and vector delivery and ex vivo cell expansion and grafting. The inside approach details systemic delivery via infusion of cells or agents toward providing benefit to the skin. We use recessive dystrophic epidermolysis bullosa (RDEB) as a representative and paradigmatic disease to showcase these approaches as a means to highlight potential broader applicability to other conditions.

Sickle cell disease (SCD) is a single-gene disorder caused by a point mutation of the β-globin gene, resulting in hemolytic anemia, acute pain, multiorgan damage, and early mortality. Hydroxyurea is a first-line drug therapy that switches sickle-globin to non-pathogenic γ-globin; however, it requires lifelong oral administration. Allogeneic hematopoietic stem cell (HSC) transplantation allows for a one-time cure for SCD, albeit with histocompatibility limitations. Therefore, autologous HSC gene therapy was developed to cure SCD in a single treatment, without HSC donors. Current HSC gene therapy is based on the ex vivo culture of patients' HSCs with lentiviral gene addition and gene editing, followed by autologous transplantation back to the patient. However, the complexity of the treatment process and high costs hinder the universal application of ex vivo gene therapy. Therefore, the development of in vivo HSC gene therapy, where gene therapy tools are directly administered to patients, is desirable to provide a more accessible, cost-effective solution that can cure SCD worldwide. In this review, we discuss current treatments including drug therapies, HSC transplantation, and ex vivo gene therapy, the development of gene therapy tools, and progress toward curative in vivo gene therapy in SCD.

Vascular endothelial growth factor B186 (VEGF-B186), a ligand for VEGF receptor 1 (VEGFR1) and neuropilin (NRP), promotes vascular growth in healthy and ischemic myocardium. However, the mechanisms and signaling of VEGF-B186 to support angiogenesis have remained unclear. We studied the effects of VEGF-B186 and its variant, VEGF-B186R127S, which cannot bind to NRPs, using VEGFR1 tyrosine kinase knockout (TK^-/-) mice to explore the mechanism of VEGF-B186 in promoting vascular growth. Ultrasound-guided adenoviral VEGF-B186, VEGF-B186R127S, and control vector gene transfers were performed into VEGFR1 TK-/- mice hearts. In vitro studies in cardiac endothelial cells and further validation in normal and ischemic pig hearts, as well as in wild-type mice, were conducted. Both VEGF-B186 forms promoted vascular growth in VEGFR1 TK^-/- mouse heart and increased the expression of proangiogenic and hematopoietic factors. Unlike VEGF-A, VEGF-B186 forms induced ER stress via the upregulation of Binding immunoglobulin Protein (BiP) as well as ER stress sensors (ATF6, PERK, IRE1α) through ITGAV and ITGA5 integrins, newly identified receptors for VEGF-B, activating the unfolded protein response (UPR) through XBP1. VEGFR1 and NRP are not essential for VEGF-B186-induced vascular growth. Instead, VEGF-B186 can stimulate cardiac regeneration through RGD-binding integrins and ER stress, suggesting a novel mechanism of action for VEGF-B186.

Chimeric antigen receptor (CAR)-T cell therapy has revolutionized cancer immunotherapy in the 21st century, providing innovative solutions and life-saving therapies for previously untreatable diseases. This approach has shown remarkable success in treating various hematological malignancies and is now expanding into clinical trials for solid tumors, such as prostate cancer and glioblastoma, as well as infectious and autoimmune diseases. CAR-T cell therapy involves harvesting a patient's T cells, genetically engineering them with viral vectors to express CARs targeting specific antigens and reinfusing the modified cells into the patient. These CAR-T cells function independently of major histocompatibility complex (MHC) antigen presentation, selectively identifying and eliminating target cells. This review highlights the key milestones in CAR-T cell evolution, from its invention to its clinical applications. It outlines the historical timeline leading to the invention of CAR-T cells, discusses the major achievements that have transformed them into a breakthrough therapy, and addresses remaining challenges, including high manufacturing costs, limited accessibility, and toxicity issues such as cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome. Additionally, the review explores future directions and advances in the field, such as developing next-generation CAR-T cells aiming to maximize efficacy, minimize toxicity, and broaden therapeutic applications.

Neutralizing antibodies (NAbs) against adeno-associated virus (AAV) represent a significant obstacle to the efficacy of systemic recombinant AAV vector administration or re-administration. While there are some promising preclinical immunomodulation strategies in development, insights into which B cell subsets and compartments maintain persistent AAV NAb may define the optimal eradication strategy. Given the limited success of CD20-directed monotherapy in previous studies, we hypothesized that CD19-directed approaches that extend targeting into the plasma cell compartments may improve AAV NAb eradication. We tested this approach in mice using chimeric antigen receptor T (CAR-T) cells or monoclonal antibodies (mAbs). We observed that combination mAbs targeting CD19, CD22, CD20, or B220 in mice did not eliminate tissue-resident B cells and, correspondingly, did not deplete pre-existing high titer AAV8 NAb. In contrast, CD19 CAR-T therapy eliminated peripheral and tissue-resident B cells and plasma cells and resulted in a marked reduction or eradication of high titer AAV8 NAb that permitted successful transgene expression following systemic AAV8 re-administration in mice. This successful therapeutic approach in mice identifies the population and location of B cells necessary to reduce or eradicate AAV NAb sufficiently to permit successful transgene expression with systemic AAV vector administration.

Glioblastoma (GBM) is an aggressive primary brain tumor with a poor prognosis and few effective treatment options. Focus has shifted toward using immunotherapies, such as chimeric antigen receptor (CAR) T cells, to selectively target tumor antigens and mediate cytotoxic activity within an otherwise immunosuppressive tumor microenvironment. Between 2015 and 2024, the results of eight completed and two ongoing phase I clinical trials have been published. The majority of studies have treated recurrent GBM patients, although the inter- and intra-patient tumor heterogeneity has been historically challenging to overcome. Molecular targets have included EGFR, HER2, and IL13Rα2 and there has been continued development in improving receptor constructs, identifying novel targets, and adding adjuvant enhancers to increase efficacy. CAR T cells have been safely administered through both peripheral and locoregional routes but with variable clinical and radiographic efficacy. Most trials utilized autologous T cell products to avoid immune rejection yet were unable to consistently show robust engraftment and persistence within patients. Nonetheless, targeted immunotherapies such as CAR T cell therapy remain the next frontier for GBM treatment, and the popularity and complexity of this undertaking is evident in the past, present, and future landscape of clinical trials.

Neonatal hypoxic-ischemic encephalopathy is aggravated by intracerebral inflammation. As pro-inflammatory microglia in the brain become activated in this condition, we aimed to establish a novel peptide therapy for neonatal hypoxic-ischemic encephalopathy by investigating the therapeutic effects of pro-inflammatory microglial depletion. MG1 homing peptide, which selectively targets and binds pro-inflammatory microglia, was conjugated with the pro-apoptotic peptide _D[KLAKLAK]₂ (KLA), creating MG1-KLA. After confirming that MG1-KLA selectively bound pro-inflammatory microglia and decreased cell viability by inducing apoptosis in a dose-dependent manner, the in vivo therapeutic effect of MG1-KLA was assessed following intracerebroventricular injection in hypoxic-ischemic encephalopathy model mice through histological, behavioral, and biochemical analyses. In these mice, MG1-KLA selectively bound to microglia and induced their apoptosis. Brain atrophy was significantly suppressed in the mice treated with MG1-KLA compared with non-treated mice. Additionally, motor function and locomotor hyperactivity were improved in mice treated with MG1-KLA compared with non-treated mice. Gene expression analysis further revealed that pro-inflammatory cytokine expression was downregulated in mice treated with MG1-KLA compared with non-treated mice. These findings suggest that novel MG1-KLA peptide therapy has high potential for treating neonatal patients with hypoxic-ischemic encephalopathy through the selective induction of apoptosis in pro-inflammatory microglia.