Project description:Recombinant adeno-associated virus (AAV) is the leading platform for gene therapy in ocular disease. Progress for gene therapy has been hindered by AAV-induced inflammation, which limits dose escalation and long-term efficacy. Characterisation of the ocular immune response to AAV in mice has been restricted to young animals and demonstrate activation of microglia, antigen presentation and a dominant T cell lymphocyte infiltration. The extent of the inflammatory response alters with age and sex and these factors have not been fully represented in the pre-clinical development of ocular AAV gene therapies. Here, we intravitreally inject a null AAV2 vector in young (3-month), middle aged (9-month) and old (18-month) Cx3cr1-creER:R26tdTomato+/- mice of both sexes. Applying clinical imaging, flow cytometric analyses and bulk-sequencing of sorted resident microglia we interrogate the impact of sex and age on the longitudinal response of both microglia and infiltrating cellular response to AAV. Young animals have a dynamic response, with a peak in inflammation at D10-12 and signs of clinical resolution by D28. Despite similar kinetics in the inflammatory response between young male and females, sex differences are observed in the magnitude of the transcriptional response by microglia and the adaptive component of the infiltrating response. With age, the inflammation increases and persists after AAV2 injection. Based on the microglia transcriptional response to AAV, males maintain similar signature across age, although enhanced with increasing age. Contrary, females have greater divergence in their inflammatory response across age. Of particular note, old females have enriched cellular stress and inflammatory microglia gene signatures, with corresponding retinal degeneration. These findings inform crucial sex and age differences for therapeutic application of ocular gene therapy. Our dataset highlight the need to further define these differences to appropriately tackle AAV immunogenicity for all populations.
Project description:Pericardial fluid is enriched by biologically active molecules of cardiovascular origin including microRNAs. Investigation of the disease-specific extracellular microRNAs could shed light on the molecular processes underlying disease development. Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited heart disease characterized by life-threatening arrhythmias and progressive heart failure development. The current data about the association between microRNAs and ARVC development are limited. We performed small RNA sequence analysis of microRNAs of pericardial fluid samples obtained during transcutaneous epicardial access for ventricular tachycardia (VT) ablation of six patients with definite ARVC and three post-infarction VT patients. Disease-associated microRNAs of pericardial fluid were identified. Enrichment analysis of differentially expressed microRNAs revealed their close linkage to cardiac diseases.
Project description:Uveitis describes a heterogeneous group of inflammatory eye diseases characterized by infiltration of leukocytes into the uveal tissues. uveitis associated with the HLA haplotype B27 (HLA-B27) is a common subtype of uveitis and a prototypical ocular immune-mediated disease. Local immune mechanisms driving human uveitis are poorly characterized mainly due to the limited available biomaterial and subsequent technical limitations. Here, we provide the first high-resolution characterization of intraocular leukocytes in HLA-B27 positive (n=3) and negative (n=2) anterior uveitis and an infectious endophthalmitis control (n=1) by combining single cell RNA-sequencing with flow cytometry and protein analysis. Ocular cell infiltrates consisted primarily of lymphocytes in both subtypes of uveitis and of myeloid cells in infectious endophthalmitis. HLA-B27 positive uveitis exclusively featured a plasmacytoid and classical dendritic cells (cDC) infiltrate. Moreover, cDCs were central in predicted local cell-cell communication. This suggests a unique pattern of ocular leukocyte infiltration in HLA-B27 positive uveitis with relevance of dendritic cells.