Biology subjects

Poznansky, M. C.

Publications and source records attributed to Poznansky, M. C..

3 recordsLinked to original sources

bioRxiv2026

Nonviral, ultrasound-triggered gene delivery platform via gas-core cationic nanobubbles

Despite their promise, lipid nanoparticle gene delivery systems have repeatedly failed clinical trials and struggle to achieve efficient, localized transfection in target tissues. The majority of endocytosed nanoparticles are degraded before nucleic acid release, and an inability to track particle distribution in vivo prevents validation of successful delivery. Alternatively, nanobubbles (NBs) are lipid-shelled, gas-core preclinical ultrasound contrast agents and stimuli-responsive drug delivery vehicles. Under varying acoustic pressures, NBs expand, contract, and burst, releasing cargo in an externally controlled, site-specific manner while scattering unique echoes for simultaneous ultrasound visualization. Here, we introduce a cationic nanobubble (CNB) formulation with a +42.3 mV zeta potential, 265 nm diameter, and 2.43x1011 NBs/mL concentration. CNBs produce stable ultrasound contrast, electrostatically load plasmid DNA onto their surface, and internalize into >99% of human prostate cancer cells within 15 minutes in vitro. CNBs remain brightly echogenic intracellularly and induce sonication-dependent expression of green fluorescent protein (GFP). In vivo, CNBs generate contrast in mouse livers for 50 minutes after intravenous administration. Therapeutic ultrasound stimulation over the liver causes a sharp reduction in ultrasound contrast, visualizing localized cavitation in the target organ and inducing a 2.5-fold increase in anti-GFP mean fluorescence intensity relative to the untransfected control. Importantly, no GFP expression is observed without ultrasound stimulation, supporting a mechanism for selective and site-specific gene delivery. This study presents a highly stable CNB capable of efficient DNA loading and ultrasound-dependent gene expression. These results provide a foundation for the future development of CNB platforms to advance image-guided, ultrasound-triggered gene therapy.

bioengineering↗

bioRxiv2021

MIAAIM: Multi-omics image integration and tissue state mapping using topological data analysis and cobordism learning

High-parameter tissue imaging enables detailed molecular analysis of single cells in their spatial environment. However, the comprehensive characterization and mapping of tissue states through multimodal imaging across different physiological and pathological conditions requires data integration across multiple imaging systems. Here, we introduce MIAAIM (Multi-omics Image Alignment and Analysis by Information Manifolds) a modular, reproducible computational framework for aligning data across bioimaging technologies, modeling continuities in tissue states, and translating multimodal measures across tissue types. We demonstrate MIAAIMs workflows across diverse imaging platforms, including histological stains, imaging mass cytometry, and mass spectrometry imaging, to link cellular phenotypic states with molecular microenvironments in clinical biopsies from multiple tissue types with high cellular complexity. MIAAIM provides a robust foundation for the development of computational methods to integrate multimodal, high-parameter tissue imaging data and enable downstream computational and statistical interrogation of tissue states.

systems biology↗

bioRxiv2019

Coxiella burnetii epitope-specific T-cell responses in chronic Q fever patients

Infection with Coxiella burnetii, the causative agent of Q fever, can result in life-threatening persistent infection. Reactogenicity hinders worldwide implementation of the only licensed human Q fever vaccine. We previously demonstrated long-lived immunoreactivity in individuals with past symptomatic and asymptomatic Coxiella infection (convalescents) to promiscuous HLA-class II C. burnetii epitopes, providing the basis for a novel T-cell-targeted subunit vaccine. Here we investigated in a cohort of 22 individuals with persistent infection (chronic Q fever) whether they recognize the same set of epitopes, or distinct epitopes that could be candidates for a therapeutic vaccine or aid in the diagnosis of persistent infection.\n\nIndividuals with chronic Q fever showed strong class II epitope-specific cultured ELISpot responses largely overlapping with the peptide repertoire identified previously for convalescents. Five additional peptides were recognized more frequently by chronic subjects, but there was no combination of epitopes uniquely recognized by or non-reactive in chronic Q fever subjects. Consistent with more recent/prolonged exposure, we found, however, stronger direct ex vivo responses to whole-cell C. burnetii and individual peptides in direct ELISpot than in convalescents.\n\nIn conclusion, we have validated and expanded a previously published set candidate epitopes for a novel T-cell targeted subunit Q fever vaccine in the context of chronic Q fever patients and demonstrated that they successfully mounted a T-cell response comparable to that of convalescents. Finally, we demonstrate that individuals treated for chronic Q fever mount a broader ex vivo response to class II epitopes than convalescents, which could be explored for diagnostic purposes.

immunology↗