Biology subjects

Silva Trenkle, A. D.

Publications and source records attributed to Silva Trenkle, A. D..

4 recordsLinked to original sources

bioRxiv2026

Supervised 3D Virtual Fluorescence and Pseudo-H&E Staining of Fresh Bulk Tissues via Multimodal qOBM and Fluorescence Microscopy

We introduce a multimodal microscope that combines quantitative oblique back-illumination microscopy (qOBM) with wide-field epi-fluorescence deconvolution microscopy to acquire intrinsically co-registered phase and fluorescence volumes of fresh, bulk tissue. Using paired qOBM phase and DAPI fluorescence images of fresh ex vivo mouse brain tissue, we train a supervised conditional generative adversarial network (cGAN) to predict DAPI-like nuclear contrast from the structural information encoded in the phase images. Results not only demonstrate high-fidelity image translation but also show improved imaging depth and more homogeneous staining. Additionally, we combine the qOBM phase contrast with captured or virtual fluorescence nuclear images to produce volumetric pseudo-H&E representations of fresh tissue, enabling a supervised approach for achieving robust virtual histological staining. This work paves the way for virtual fluorescence imaging of many more structural targets and supervised virtual histological staining of thick, unaltered, bulk tissues ex vivo and potentially in vivo. Such capabilities could have significant implications for biological research as well as for point-of-care, intraoperative, and other clinical applications.

bioengineering↗

bioRxiv2025

Non-destructive, high-resolution T cell characterization and subtyping via deep-ultraviolet microscopy

T cell characterization is critical for understanding immune function, monitoring disease progression, and optimizing cell-based therapies. Current technologies to characterize T cells, such as flow cytometry, require fluorescent labeling and typically are destructive endpoint measurements. Non-destructive, label-free imaging methods have been proposed, but face limitations with throughput, specificity, and system complexity. Here we demonstrate deep-ultraviolet (UV) microscopy as a label-free, non-destructive, fast and simple imaging approach for assessing T cell viability, activation state, and subtype with high accuracy. Using static deep-UV images, we characterize T cell viability and activation state, demonstrating excellent agreement with flow cytometry measurements. We further apply dynamic deep-UV imaging to quantify intracellular activity, enabling fast and accurate subtyping of CD4+ and CD8+ T cells. These results corroborate recent studies on metabolic activity differences between these subtypes, but now with deep-UV microscopy they are enabled by a non-destructive, fast, low-cost and simple approach. Together, our results demonstrate deep-UV microscopy as a powerful tool for high-throughput immune cell characterization, with broad applications in immunology re-search, immune monitoring, and development of emerging cell-based therapies.

immunology↗

bioRxiv2025

Label-Free In-Line Characterization of Immune Cell Culture using Quantitative Phase Imaging

Cell therapies, including T cell immunotherapies, offer promising treatments for previously untreatable diseases, but their widespread use is hindered by challenges in monitoring therapeutic cells during culture--impacting consistency, potency, and cost. This work demonstrates the use of quantitative phase imaging (QPI), specifically a compact, non-interferometric form called quantitative oblique back illumination microscopy (qOBM), for non-destructive, label-free, in-line assessment of T cell cultures. qOBM enables near real-time feedback on culture growth, contamination, and cell status (viability and activation), comparable to flow cytometry. We further apply this method to characterize genetically modified CAR T cells and explore its potential for advanced T cell phenotyping. Analysis of data from over 50 independent donors shows strong correlation between qOBM metrics and traditional destructive at-line assays. Overall, qOBM provides a powerful tool for continuous, in-line monitoring of therapeutic cell cultures, which can be transformative for improving reproducibility, reducing costs, and advancing the development of cell-based therapies.

immunology↗

bioRxiv2021

In vivo mRNA delivery to virus-specific T cells by light-induced ligand exchange of MHC class I antigen-presenting nanoparticles

Simultaneous delivery of mRNA to multiple populations of antigen (Ag)-specific CD8+ T cells is challenging given the diversity of peptide epitopes and polymorphism of class I major histocompatibility complexes (MHCI). We developed Ag-presenting nanoparticles (APNs) for mRNA delivery using pMHCI molecules that were refolded with photocleavable peptides to allow rapid ligand exchange by UV light and site-specifically conjugated with a lipid tail for post-insertion into preformed mRNA lipid nanoparticles. Across different TCR transgenic mouse models (P14, OT-1, Pmel), UV-exchanged APNs bound and transfected their cognate Ag-specific CD8+ T cells equivalent to APNs produced using conventionally refolded pMHCI molecules. In mice infected with PR8 influenza, multiplexed delivery of UV-exchanged APNs against three immunodominant epitopes led to ~50% transfection of a VHH mRNA reporter in cognate Ag-specific CD8+ T cells. Our data shows that UV-mediated peptide exchange can be used to rapidly produce APNs for mRNA delivery to multiple populations of Ag-specific T cells in vivo. TeaserLight-induced rapid production of antigen-presenting nanoparticles for mRNA delivery to multiple virus-specific T cell populations.

bioengineering↗