Corneal blindness affects greater than 5 million individuals, with over 180,000 corneal transplantations (CTs) performed annually. Inhigh-risk CTs, almost all grafts are rejected within 10 years. Herein, adeno-associated virus (AAV) ex vivo gene therapy was investigated to establish immune tolerance in the corneal allograft to prevent high-risk CT rejection. Our previous work has demonstrated that HLA-G contributes to ocular immune privilege by inhibiting both immune cells and neovascularization; however, homodimerization is a rate-limiting step for optimal HLA-G function. Therefore, a chimeric protein termed single chain immunomodulator (sclM), was engineered to mimic the native activity of the secreted HLA-G dimer complex and eliminate the need for homodimerization. In a murine corneal burn model, AAV8-sclM significantly reduced corneal vascularization and fibrosis. Next, ex vivo AAV8-scIM gene delivery to corneal allografts was evaluated in a high-risk CT rejection rabbit model. All sclM treated corneas were well tolerated and transparent after 42 days while 83% of vehicle treated corneas were rejected. Histologically, AAV-scIM treated corneas were devoid of immune cell infiltration, vascularization, with minimal fibrosis at the host-graft interface. The data collectively demonstrate that sclM gene therapy prevents corneal neovascularization, reduces trauma-induced corneal fibrosis, and prevents allogeneic CT rejection in a high-risk large animal model.
Intratumoral regulatory T cells (Tregs) express high levels of CD25 and TIGIT, which are also recognized as markers of effector T cell (Teff) activation. Targeting these molecules each alone with monoclonal antibodies (mAbs) poses a risk of concurrently depleting both Teffs and peripheral Tregs, thereby compromising the effectiveness and selectivity of intratumoral Treg depletion. Here, leveraging the increased abundance of CD25+ TIGIT+ double positive Tregs in the solid tumor microenvironment (but not in peripheral tissues), we explored the feasibility of using a CD25×TIGIT bispecific antibody (bsAb) to selectively deplete intratumoral Tregs. We initially constructed a bsAb co-targeting mouse CD25 and TIGIT, NSWm7210, and found that NSWm7210 conferred enhanced intratumoral Treg depletion, Teff activation, and tumor suppression as compared to the parental monotherapies in mouse models. We subsequently constructed a bsAb co-targeting human CD25 and TIGIT (NSWh7216), which preferentially eliminated CD25+ TIGIT+ double positive cells over single positive cells in vitro. NSWh7216 exhibited enhanced anti-tumor activity without toxicity of peripheral Tregs in CD25 humanized mice compared to the parental monotherapies. Our study illustrates the use of CD25×TIGIT bsAbs as effective agents against solid tumors based on selective depletion of intratumoral Tregs.
Under compassionate use, chimeric antigen receptor (CAR) T-cells have elicited durable remissions in patients with refractory idiopathic inflammatory myopathies (IIM)1. Here, we report on the safety, efficacy, and correlative data of the first subject with the immune-mediated necrotizing myopathy (IMNM) subtype of IIM who received a fully human, 4-1BBz anti-CD19-CAR T-cell therapy (CABA-201) in the RESET-Myositis™ phase I/II trial (NCT06154252). CABA-201 was well-tolerated following infusion. Notably, no evidence of cytokine release syndrome (CRS) or immune effector-cell associated neurotoxicity syndrome (ICANS) was observed. CK levels decreased, and muscular strength improved post-infusion. Peripheral B-cells were depleted rapidly following infusion, and the subject achieved peripheral B-cell aplasia by day 15 post-infusion. Peripheral B-cells returned at 2 months post-infusion and were almost entirely transitional. Autoantibodies to SRP-9, SRP-72, SRP-54, and Ro-52, decreased relative to baseline whereas antibodies associated with pathogens and vaccinations remained stable. The infusion product consisted of predominantly CD4+ effector memory T-cells & exhibited in vitro cytolytic activity. Post-infusion, CABA-201 expansion peaked at day 15 and was preceded by a serum IFN-γ peak on day 8 with peaks in serum IL-12p40 and IP-10 on day 15. These data detail the safety, efficacy, and pharmacodynamics of CABA-201 in the first IMNM subject.
Wnt/β-catenin signaling is an attractive target for regenerative medicine. A powerful driver of stem cell activity and hence tissue regeneration, Wnt signaling can promote fibroblast proliferation and activation, leading to fibrosis, while prolonged Wnt signaling is potentially carcinogenic. Thus, to harness its therapeutic potential, the activation of Wnt signaling must be transient, reversible and tissue-specific. In the lung, Wnt signaling is essential for alveolar stem cell activity and alveolar regeneration, which is impaired in lung fibrosis. Activation of Wnt/β-catenin signaling in lung epithelium may have anti-fibrotic effects. Here, we used intratracheal AAV6 injection to selectively deliver CasRx into lung epithelium, where it reversibly activates Wnt signaling by simultaneously degrading mRNAs encoding Axin1 and Axin2, negative regulators of Wnt/β-catenin signaling. Interestingly, CasRx mediated Wnt activation specifically in lung epithelium not only promotes alveolar type II cell (AT2) proliferation and alveolar regeneration, but also inhibits lung fibrosis resulted from bleomycin-induced injury, relevant in both preventive and therapeutic settings. Our study offers an attractive strategy for treating pulmonary fibrosis, with general implications for regenerative medicine.
Prostate-cancer (PC) is a leading cause of cancer-related deaths in men worldwide. Interleukin-(IL)-30 is a PC-progression driver, and its suppression would be strategic for fighting metastatic disease. Biocompatible Lipid-Nanoparticles (NPs) were loaded with CRISPR/Cas9gRNA to delete human(h)IL30-gene and functionalized with anti-PSCA-Abs (Cas9hIL30-PSCA-NPs). Efficiency of the NPs in targeting IL30 and metastatic potential of PC cells was examined in vivo, in xenograft models of lung metastasis, and in vitro, by using 2-Organ-on-Chip (2-OC), containing 3D-spheroids of IL30+PC-Endothelial-Cell(EC) co-cultures in circuit with either Lung-mimicking-spheroids, or Bone-marrow(BM)-niche-mimicking-scaffolds. Cas9hIL30-PSCA-NPs demonstrated circulation stability, genome editing efficiency, without off-target effects and organ toxicity. Intravenous injection of three-doses/13-days, or five-doses/20-days, of NPs in mice bearing circulating PC cells and micro-emboli substantially hindered lung metastasization. Cas9hIL30-PSCA-NPs inhibited PC cell proliferation and expression of IL30 and metastasis-drivers, such as CXCR2, CXCR4, IGF1, L1CAM, METAP2, MMP2 and TNFSF10, whereas CDH1 was up-regulated. PC-Lung and PC-BM 2-OCs revealed that Cas9hIL30-PSCA-NPs suppressed PC cell release of CXCL2/GROβ, which in vivo was associated with intra-metastatic myeloid cell infiltrates, and of DKK1, OPG and IL6, which in vitro boosted endothelial-network formation and cancer cell migration. Development of a patient-tailored nanoplatform for selective CRISPR-mediated IL30 gene deletion is a clinically valuable tool against PC progression.
Chimeric antigen receptor (CAR) T-cell therapy showed preliminary activity in patients with refractory or relapsed T-cell acute lymphoblastic leukemia (r/r T-ALL). However, many obstacles remain, including manufacturing difficulties and risk of infections. This phase I study (NCT04840875) evaluated autologous CD7 CAR T cells manufactured without pre-selection of healthy T cells in r/r T-ALL. Thirty patients (29 children and one adult) with a median of two lines of prior therapy but without detectable peripheral leukemia were enrolled. Excluding three cases of manufacturing failures, a total of 27 (90%) patients received infusions after products were confirmed free of leukemia contamination, including 16 (59%) meeting planned target doses. Common adverse events within 30 days included grade 3-4 cytopenias (100%), grade 1-2 (70%) and 3-4 (7%; including one dose-limiting toxicity) cytokine release syndrome, grade 1 neurotoxicity (7%), grade 2 infection (4%), and grade 2 graft-versus-host disease (4%). Two patients developed grade 2 infections after day 30. At day 30, 96% responded and 85% achieved CR or CRi. 74% underwent transplantation. Twelve-month progression-free survival with and without censoring transplantation was 22% (95%CI 4-100) and 57% (41-81), respectively. These results support that autologous CD7 CAR T-cell therapy without T-cell pre-selection is feasible in patients with r/r T-ALL.
T cell-redirecting therapies (TCRTs), such as chimeric antigen receptor (CAR) or T cell receptor (TCR) T cells and T cell engagers, have emerged as a highly effective treatment modality, particularly in the B and plasma cell-malignancy setting. However, many patients fail to achieve deep and durable responses; while the lack of truly unique tumor antigens, and concurrent on-target/off-tumor toxicities, have hindered the development of TCRTs for many other cancers. In this review, we discuss the recent developments in TCRT targets for hematological malignancies, as well as novel targeting strategies that aim to address these, and other, challenges.