Szabo, V. | bioRxiv Science

bioRxiv2025

CoreTIA: a modular, statistically robust transduction inhibition assay for AAV neutralization

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. coreTIAs 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.

immunology↗

bioRxiv2020

Decreased calmodulin recruitment triggers PMCA4 dysfunction and pancreatic injury in cystic fibrosis

Exocrine pancreatic damage is a common complication of cystic fibrosis (CF), which can significantly debilitate the quality of life and life expectancy of CF patients. The cystic fibrosis transmembrane conductance regulator (CFTR) has a major role in pancreatic ductal ion secretion, however, it presumably has an influence on intracellular signaling as well. Here we describe in multiple model systems, including iPSC-derived human pancreatic organoids from CF patients, that the activity of PMCA4 is impaired by the decreased expression of CFTR in ductal cells. The regulation of PMCA4, which colocalizes and physically interacts with CFTR on the apical membrane of the ductal cells, is dependent on the calmodulin binding ability of CFTR. Moreover, CFTR seems to be involved in the process of the apical recruitment of calmodulin, which enhances its role in calcium signaling and homeostasis. Sustained intracellular Ca2+ elevation in CFTR KO cells undermined the mitochondrial function and increased apoptosis. Based on these, the prevention of sustained intracellular Ca2+ overload may improve the exocrine pancreatic function and may have a potential therapeutic aspect in CF.

cell biology↗