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Green, J. J.

Publications and source records attributed to Green, J. J..

5 recordsLinked to original sources

Suprachoroidal Delivery of Anti-Angiogenic Peptide Microparticles Enables Sustained Activity with Favorable Ocular Safety

Retinal and choroidal vascular diseases are major causes of vision loss that require frequent intravitreal anti-VEGF therapy. Anti-angiogenic peptide AXT107 demonstrated efficacy in preclinical studies and was advanced to the clinical stage. To provide for sustained delivery of the peptide and avoid complications with intravitreal injection, we evaluated suprachoroidal delivery of AXT107 microparticles (MP-AXT107). The original, soluble AXT107 formulation was ineffective at inhibiting laser-induced choroidal neovascularization (CNV) in our rat model and was consequently reformulated as microparticles. MP-AXT107 demonstrated high peptide incorporation efficiency, reproducible morphology, and physical and chemical stability for at least 9 months under refrigerated storage. In the rat CNV model, suprachoroidal MP-AXT107 significantly reduced neovascular area by approximately 60% relative to vehicle controls. Safety and durability were evaluated in a 9-month GLP toxicology study in Gottingen minipigs following a single suprachoroidal injection of vehicle or MP-AXT107 (0.125-1.25 mg/eye). Transient increases in IOP and mild ocular inflammatory findings were observed immediately following administration but resolved rapidly without lasting effects. No treatment-related adverse ocular findings were observed during the remainder of the study, and the highest tested dose (1.25 mg/eye) was established as the no-observed-adverse-effect level. Bioanalysis at study completion demonstrated persistent AXT107 localization primarily within choroid/RPE and scleral tissues, with no signs of systemic exposure. Collectively, these findings demonstrate that suprachoroidal delivery of MP-AXT107 enables sustained anti-angiogenic activity with favorable ocular safety and prolonged tissue retention, supporting further clinical development as a durable therapy for retinal and choroidal vascular diseases.

pharmacology and toxicology↗

Base editing and nanoparticle transfection of airway cell types essential for treatment of cystic fibrosis

Cystic Fibrosis (CF) is a life-limiting genetic disorder caused by deleterious variants in the CFTR gene that results in altered mucous impairing the airway epithelia. Durable correction of these variants in airway cells remain a therapeutic challenge for [~]10% of individuals unresponsive to CFTR modulators. A common disease-causing CFTR splice site variant was corrected in primary CF airway cells using base editor RNAs. Single-cell RNA sequencing revealed a remarkable increase in detectable CFTR transcript in most CF airway epithelial cell types with notable enrichment of CFTR-expressing ionocytes and secretory goblet cells. Progenitor basal cell subtypes were edited but they decreased as a fraction of total cells and CFTR expressing cells compared to unedited cells. CRISPR base editors delivered by polymeric nanoparticles (PNPs) facilitated functional rescue of CFTR to clinically meaningful levels in immortalized and primary airway cells. PNPs delivered reporter encoding RNA to progenitor airway cells in fully differentiated airway cultures. Vitronectin was a major component of the PNP corona that formed in vivo, but pre-incubation with vitronectin did not enhance delivery. Together, these findings validate a scalable, non-viral platform with significant translational promise for treating CF and other respiratory diseases involving respiratory epithelial cell dysfunction.

genetics↗

Inhibition of Yes-Associated Protein (YAP) with Verteporfin Enhances Radiosensitivity in Chordoma by Inducing G2M Arrest and Inhibiting the DNA Damage Response

Chordomas are locally invasive cancers that are highly resistant to radiotherapy. The Brachyury and Yes-Associated Protein (YAP) regulatory axis has been implicated as the primary driver of tumorigenicity in chordoma. Here, we aimed to enhance chordoma radiosensitivity by repurposing the FDA-approved YAP inhibitor, Verteporfin. We used five patient-derived chordoma cell lines and generated two YAP1 knockdown cell lines to validate the YAP-targeting phenotype in chordoma. Verteporfin treatment reduced the expression of DNA damage repair proteins and genes. YAP inhibition with either verteporfin or YAP knockdown resulted in enhanced DNA double-stranded breaks after radiation via inhibition of the DNA damage repair pathway and accumulation of cells in the G2M phase. Verteporfin inhibited chordoma tumor growth alone and in combination with radiation in a xenograft mouse model treated with verteporfin loaded microparticles, resulting in sensitization of chordoma tumors to radiation. YAP inhibition with verteporfin renders chordoma more sensitive to radiation via inhibition of the DNA damage repair cascade and accumulation of cells in G2M when they are most susceptible to radiation damage.

cancer biology↗

Audiovisual Integration in the Human Brain: A Coordinate-based Meta-analysis

People can seamlessly integrate a vast array of information from what we see and hear in the noisy and uncertain world. However, the neural underpinnings of audiovisual integration continue to be the topic of debate. Using strict inclusion criteria, we performed activation likelihood estimation meta-analysis on 121 neuroimaging experiments with a total of 2,092 participants. We found that audiovisual integration is linked with the coexistence of multiple integration sites including early cortical, subcortical, and higher association areas. Although activity was consistently found within the superior temporal cortex, different portions of this cortical region were identified depending on the analytical contrast used, complexity of the stimuli, and modality within which attention was directed. The context-dependent neural activity related to audiovisual integration suggests a flexible rather than fixed neural pathway for audiovisual integration. Together, our findings highlight a flexible multiple pathways model for audiovisual integration, with superior temporal cortex as the central node in these neural assemblies.

neuroscience↗

Combinatorial library of biodegradable polyesters enables delivery of plasmid DNA to polarized human RPE monolayers for retinal gene therapy

AbstractEfficient gene delivery into hard-to-transfect cells is still a challenge despite significant progress in the development of various gene delivery tools. Non-viral and synthetic polymeric nanoparticles offer an array of advantages for gene delivery over the viral vectors and high in demand as they are safe to use, easy to synthesize and highly cell-type specific. Here we demonstrate the use of a high-throughput screening (HTS) platform to screen for biodegradable polymeric nanoparticles (NPs) that can transfect human retinal pigment epithelial (RPE) cells with high efficiency and low toxicity. These NPs can deliver plasmid DNA (pDNA) to RPE monolayers more efficiently compared to the commercially available transfection reagents without interfering the global gene expression profile of RPE cells. In this work, we have established an HTS platform and identified synthetic polymers that can be used for high efficacy non-viral gene delivery to human RPE monolayers, enabling gene loss- and gain-of-function studies of cell signaling and developmental pathways. This platform can be used to identify the optimum polymer, weight-to-weight ratio of polymer to DNA, and the dose of NP for various retinal cell types.

bioengineering↗