Abstract T cell immune tolerance is established in part through the activity of the Auto-immune Regulator (AIRE) transcription factor in the medullary Thymic Epithelial Cells (mTEC) of the thymus. AIRE induces expression of SELF peripheral tissue-specific antigens for presentation to naïve T cells to promote activation/deletion of potentially autoreactive T cells. We show, for the first time to our knowledge, that tumors mimic the role of AIRE in mTEC to evade immune rejection. Thus, by expressing a broad range of SELF epitopes against which minimal functional T cell reactivities exist because of thymic deletion, AIRE acts as a master controller of SELFNESS, effectively cloaking the tumor from T cell attack. Moreover, we describe a completely novel immunotherapy in which engineered changes in AIRE expression in tumor cells alters their profile of SELFNESS, exposing both AIRE-modified, and parental unmodified, tumor cells to T cell attack. Consistent with our studies, patient RNAseq shows expression of AIRE predicts response to immune therapies with a strong correlation between AIRE expression and markers of TCR signaling. Therefore, by re-setting the immunological SELFNESS of cancer cells, this novel AIRE-mediated immunotherapy 1). converts a highly tolerized T cell compartment into a heteroclitic tumor-reactive T cell population; 2) confers de novo sensitivity to immune checkpoint blockade upon non-immunogenic tumors; 3). completely removes the need to identify potentially immunogenic tumor-associated antigens as targets for generation of de novo CD8+ and helper CD4+ T cell responses; and 4) leads to potent T cell-mediated rejection of aggressive, immunologically cold, non-immunogenic tumors.
Oncolytic virus–mediated expansion of dual-specific CAR T cells improves efficacy against solid tumors in mice
Oncolytic viruses (OVs) encoding a variety of transgenes have been evaluated as therapeutic tools to increase the efficacy of chimeric antigen receptor (CAR)–modified T cells in the solid tumor microenvironment (TME). Here, using systemically delivered OVs and CAR T cells in immunocompetent mouse models, we have defined a mechanism by which OVs can potentiate CAR T cell efficacy against solid tumor models of melanoma and glioma. We show that stimulation of the native T cell receptor (TCR) with viral or virally encoded epitopes gives rise to enhanced proliferation, CAR-directed antitumor function, and distinct memory phenotypes. In vivo expansion of dual-specific (DS) CAR T cells was leveraged by in vitro preloading with oncolytic vesicular stomatitis virus (VSV) or reovirus, allowing for a further in vivo expansion and reactivation of T cells by homologous boosting. This treatment led to prolonged survival of mice with subcutaneous melanoma and intracranial glioma tumors. Human CD19 CAR T cells could also be expanded in vitro with TCR reactivity against viral or virally encoded antigens and was associated with greater CAR-directed cytokine production. Our data highlight the utility of combining OV and CAR T cell therapy and show that stimulation of the native TCR can be exploited to enhance CAR T cell activity and efficacy in mice.
Minimal Residual Disease in Neovascular Age-Related Macular Degeneration
AbstractWith the advent of long-acting anti-vascular endothelial growth factor substances, “healing of AMD (age-related macular degeneration)” might be easily assumed due to prolonged treatment intervals. Adoption of the oncological concept of minimal residual disease for quiescent choroidal neovascularization (CNV) lesions might enhance the importance of continued monitoring, and spur research into the core of the disease, i.e., CNV biology.
Histologic Findings of Choroidal Vasculopathy in Eyes Enucleated following Radiation Therapy for Uveal Melanoma: Radiation Choroidopathy
Abstract Introduction Little has been published about the choroidal vascular changes that occur years after radiation exposure. The aim of this study was to review the histological changes observed in the choroidal vasculature following radiotherapy for uveal melanoma. Methods Records from a single institution were retrospectively reviewed from June 7, 2007 to June 7, 2017; 101 patients with a diagnosis of uveal melanoma that underwent enucleation had their records reviewed. Out of these, a total of 26 eyes had undergone plaque brachytherapy prior to enucleation, which had been performed at a mean time of 7.2 years (range from 0 years to 30 years) after the initial plaque placement. A histopathologic analysis was conducted on all 26 eyes with special emphasis on the choroidal changes. Of these 26 eyes, 18 demonstrated evidence of radiation-induced vasculopathy. Results Of the 18 eyes, 10/18 (55%) had radiation retinopathy and 16/18 (89%) had radiation choroidal vasculopathy. One patient had a phthisical eye, and the choroid could not be evaluated because the characteristics of the vasculature could not be determined. Nine cases had vitreous hemorrhage (50%), all cases had radiation retinopathy, and 8/9 (89%) had radiation choroidopathy. Of the 16 cases with radiation choroidal vasculopathy, 3/16 (19%) had only intratumoral radiation choroidal vasculopathy, 3/16 (19%) had only extratumoral radiation choroidal vasculopathy, and, thus, 10/16 (32%) had both intratumoral and extratumoral radiation choroidal vasculopathy. In patients with radiation choroidal vasculopathy, 2/16 (13%) had hyalinization of the choroidal vessels. Another 3/16 (19%) cases with radiation choroidal vasculopathy had ectatic vessels. The other 11/16 (68%) had evidence of both hyalinization of the choroidal vessels as well as ectatic vessels in the choroid. Histological evidence of radiation retinopathy and choroidopathy were seen in 69% of eyes enucleated after receiving radiation therapy, which, in some cases, also had vitreous hemorrhage. Polypoidal choroidal vasculopathy, choroidal neovascularization, and retinal choroidal anastomoses (RAP-type lesions) were seen in 12 of the 16 eyes (75%). Discussion/Conclusion Irradiation of malignant tumors of the eye causes not only radiation retinopathy but also radiation choroidopathy. The role of radiation choroidopathy in the subsequent visual loss following radiotherapy and the role of anti-VEGF therapy needs to be recognized and distinguished from radiation retinopathy. Our data adds to the prior limited knowledge that radiation affects the choroid and can induce specific phenotypes similar to the clinical spectrum of CNV, PCV, and RAP.
Introduction: Antineutrophil cytoplasm antibody-associated vasculitides encompass a diverse spectrum of autoimmune diseases characterized by necrotizing small vessel vasculitis. Ocular manifestations may be the presenting findings of antineutrophil cytoplasm antibody-associated vasculitides. Methods: Single, retrospective case study. Results: We report the rare case of a 55-year-old woman with a cilioretinal artery occlusion as the presenting feature of perinuclear antineutrophil cytoplasm antibody-associated microscopic polyangiitis. Conclusions: Although rare, antineutrophil cytoplasm antibody-related vasculitis should be considered in any retinal vascular occlusion, particularly in the setting of patients with new vague headaches and a paucity of vasculopathic risk factors.
Phase 1 study of pomalidomide and dexamethasone for relapsed/refractory primary CNS or vitreoretinal lymphoma
AbstractThe combination of pomalidomide (POM) and dexamethasone (DEX) was evaluated for relapsed/refractory primary central nervous system lymphoma (PCNSL) and primary vitreoretinal lymphoma (PVRL) to determine the maximal tolerated dose (MTD) of POM as the primary objective, and overall response rate (ORR), progression-free survival (PFS), and safety profile as secondary objectives. A cohorts-of-3 study design was used with a dose-escalation schedule consisting of POM (3, 5, 7, or 10 mg) orally daily for 21 days every 28 days and DEX 40 mg orally every week. After 2 cycles, POM was continued alone until disease progression, intolerance, or subject withdrawal. Following MTD determination, the MTD cohort was expanded. Twenty-five of 29 patients with the median of 3 prior treatments were eligible for assessment as per international PCNSL collaborative group criteria. The MTD of POM was 5 mg daily for 21 days every 28 days. Whole-study ORR was 48% (12 of 25; 95% confidence interval [CI], 27.8%, 68.7%) with 6 complete response (CR), 2 complete response, unconfirmed (CRu), and 4 partial response (PR). MTD cohort ORR was 50% (8 of 16; 95% CI, 24.7%, 75.4%) with 5 CR, 1 CRu, and 2 PR. Median PFS was 5.3 months (whole study) and 9 months (for responders). One patient had pseudoprogression. Grade 3/4 hematologic toxicities included neutropenia (21%), anemia (8%), and thrombocytopenia (8%). Grade 3/4 nonhematologic toxicities included lung infection (12%), sepsis (4%), fatigue (8%), syncope (4%), dyspnea (4%), hypoxia (4%), respiratory failure (8%), and rash (4%). POM/DEX treatment is feasible with significant therapeutic activity against relapsed/refractory PCNSL and PVRL. This trial was registered at www.clinicaltrials.gov as #NCT01722305.