Brainvest (Hungary)

Sensitive quantification of adeno-associated virus (AAV) neutralizing antibodies (NAbs) is essential for gene therapy success. Conventional cell-based transduction inhibition assays often encounter matrix-induced artifacts resulting from variable serum content across dilutions, which artificially inflate transduction baselines and mask partial neutralization. To address this challenge, we developed the constant serum concentration (CSC) assay, which maintains constant serum levels across dilutions to stabilize assay baselines and enhance NAb detection sensitivity. Using human sera across multiple AAV serotypes, we demonstrated that CSC reclassified up to 21.7% of samples classified as non-neutralizing by a conventional variable serum concentration (VSC) assay format. This improved sensitivity was validated using monoclonal antibody and multi-species serum test benchmarks and enhanced the reliability of seronegative control pool selection. Importantly, CSC detected persistent seropositivity in preclinical seroreversion models up to one year longer than a conventional VSC assay. Since even low-level neutralizing antibodies can significantly impact gene therapy efficacy, these findings have direct implications for optimizing AAV redosing strategies and refining patient stratification. By addressing fundamental limitations in NAb quantification while maintaining procedural simplicity, the CSC assay provides crucial insights into antibody persistence with translational relevance across species and clinical settings.

Abstract Adeno-associated virus (AAV) gene therapy is often limited by pre-existing neutralizing antibodies (NAbs), yet current assays for NAb detection lack standardization and rarely quantify uncertainty, complicating cross-study comparisons. We present coreTIA (core Transduction Inhibition Assay), a modular experimental protocol combined with a statistically robust analysis pipeline that delivers precise, reproducible NAb titers with quantified uncertainty for every result. coreTIA’s statistical framework enables robust estimation of neutralization even when dilution series are incomplete, helping to reduce repeat testing and minimizing sample volume requirements. Evaluation and refinement of key assay parameters support consistent performance across AAV serotypes. By providing a protocol and analysis suite as an open resource, coreTIA facilitates more consistent and transparent NAb measurement, potentially aiding assay harmonization and regulatory assessment, addressing a key barrier to progress in gene therapy research and development.

Abstract We prepared numerous thiazole derivatives from push‐pull alkenes such as nitroenamines, enaminoester, and enaminonitrils in a two‐step reaction with thiocyanate ion. The first step was the formation of the thiocyanate‐substituted push‐pull alkene from an iodine‐containing intermediary. We demonstrated this sequence through the preparation and identification of the iodine‐substituted enamines. In the second step, thiazole ring closure took place in methanol, at room temperature. The imino group of the condensed thiazole ring systems was successfully acylated. The same reaction sequence with potassium selenocyanate resulted in two selenocyanate and a selenazole heterocyclic derivatives. The mechanism of the reaction with thiocyanate ion and the heterocycle formation was investigated by computational methods. We performed quantum chemical calculations, involving both the thermodynamic and the kinetic aspects of the ring closure reaction.

Abstract The organism-wide effects of viral infection SARS-CoV-2 are well studied, but little is known about the dynamics of how the infection spreads in time among or within cells due to the scarcity of suitable high-resolution experimental systems. Two-photon (2P) imaging combined with a proper subcellular staining technique has been an effective tool for studying mechanisms at such resolutions and organelle levels. Herein, we report the development of a novel calcium sensor molecule along with a 2P-technique for identifying imaging patterns associated with cellular correlates of infection damage within the cells. The method works as a cell viability assay and also provides valuable information on how the calcium level and intracellular distribution are perturbed by the virus. Moreover, it allows the quantitative analysis of infection dynamics. This novel approach facilitates the study of the infection progression and the quantification of the effects caused by viral variants and viral load.

With the appearance of micromachined mechanical elements and nanotechnology increased demand can be observed for coordinate tables having submicron position accuracy. The paper describes the construction of a small (100/spl times/100mm) high precision (0,01 /spl mu/m resolution, less then 0,1 /spl mu/m measuring accuracy over the full range) coordinate table. It was decided to design a modular system with independent metrological and structural frames. The construction enables the application of various measuring element like optical grid or laser interferometer combined with capacitive sensors to supervise the gap between the table and the guiding surface. The table was developed as part of an optical co-ordinate measuring machine intended for the quality control of filaments and filament assemblies for energy saving bulbs.