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Biology subjects

Lavickova, B.

Publications and source records attributed to Lavickova, B..

7 recordsLinked to original sources

CORE: Deterministic alignment for bias-free organoid histology

Histological analysis of 3D tissue models is limited by geometric sampling bias arising from inconsistent positioning during embedding. We present Coplanar Organoid Reproducible Embedding (CORE), which aligns heterogeneous specimens on a shared sectioning plane to enable reproducible, bias-free histology. By eliminating depth-dependent sampling artifacts, CORE reveals biological differences obscured by sectioning depth and integrates with automated liquid- handling workflows.

bioengineering↗

Organoid-based colorectal tumor microenvironment model for immuno-oncology research

The development of cancer immunotherapies is hindered by the lack of human-relevant models that accurately translate to patient outcomes. We combine patient-derived colorectal tumor organoids (PDOs) and cancer-associated fibroblasts (CAFs) into floating extracellular matrix drops to form miniature colorectal tumors. These SHaking Organoid CO-cultures (SHOCOs) reproducibly capture key features of the tumor microenvironment (TME), including physiologically relevant ECM, hypoxic regions, and a diversified stromal compartment that captures primary CAF states. Compared with traditional PDO-based co-culture models, SHOCOs maintain immune cells in numbers, states and functional interactions that more closely reflect the physiological tumor microenvironment. The modularity of the system allowed controlled simulation of diverse patient tumor archetypes, and defining how TME components shape therapy response. Immune-rich SHOCOs treated with T-cell bispecific antibodies exhibited robust anti-tumor responses that were stronger and more rapid than their PDO-based counterparts. Stroma-rich tumors, on the other hand, diminished therapy responses by physically hindering both immune cell recruitment and limiting antibody penetration. Thus, SHOCOs enable the construction of modular tumor microenvironments, providing a versatile platform to dissect immune and stromal tumor biology and to catalyze the discovery of novel therapeutic approaches.

cancer biology↗

Integrated Microfluidic Platform for High-Throughput Generation of Intestinal Organoids in Hydrogel Droplets

Organoid research offers valuable insights into human biology and disease, but reproducibility and scalability remain significant challenges, particularly for epithelial organoids. Here, we present an integrated microfluidic platform that addresses these limitations by enabling high-throughput generation of uniform hydrogel microparticles embedded with intestinal stem cells. Our platform includes a cell distribution system for homogenous cell encapsulation and a microfluidic oil removal module for efficient particle transfer to aqueous media. We demonstrate the successful culture and differentiation of both healthy and tumor-derived intestinal organoids within these microparticles, achieving high homogeneity and reproducibility. This integrated microfluidic approach holds promise for scalable and standardized organoid production, with potential applications in drug screening, disease modeling, and personalized medicine.

bioengineering↗

High-throughput histopathology for complex in vitro models

Human complex in vitro models (CIVMs) have demonstrated remarkable potential to study tissue development, physiology and disease at high-throughput. To effectively employ these miniaturized systems in translational preclinical research, their in-depth benchmarking is pivotal. Histology has been the core of tissue characterization for centuries and the foundation of spatial phenotyping. However, standard histology workflows are inherently low-throughput and centered on large tissue pieces. This does not match the high sample volumes and small sample sizes in CIVM research. Here, we introduce a holistic histo-workflow, utilizing 3D-printed histomolds that facilitate co-planar embedding of CIVMs at high-throughput, resulting in up to 48 samples in one section. We developed a variety of model-specific histomold designs that enable spatially controlled histological sectioning and downstream analyses. We describe these workflows, including mold generation, highplex staining and image analysis, and exemplify their application to histological analyses of various CIVMs. Altogether, the histomolds introduced here afford opportunities for CIVM processing and analysis, while significantly reducing labor and reagent resources, thereby democratizing high-throughput CIVM in histopathology.

pathology↗

Improved cell-free transcription-translation reactions in microfluidic chemostats augmented with hydrogel membranes for continuous small molecule dialysis

Increasing protein production capacity of the PURE cell-free transcription-translation (TX-TL) system will be key to implementing complex synthetic biological circuits, and to establish a fully self-regenerating system as a basis for the development of a synthetic cell. Under steady-state conditions, the protein synthesis capacity of the PURE system is likely at least one order of magnitude too low to express sufficient quantities of all PURE protein components. This is in part due to the fact that protein synthesis cant be sustained during the entire dilution cycle, especially at low dilution rates. We developed a microfluidic chemostat augmented with semi-permeable membranes that combines steady-state reactions and continuous dialysis as a possible solution to enhance protein synthesis at steady-state. In batch operation, the continuous dialysis of low molecular weight components via the membranes extended protein synthesis by over an order of magnitude from 2 hours to over 30 hours, leading to a seven-fold increase in protein yield. In chemostat operation, continuous dialysis enabled sustained protein synthesis during the entire dilution cycle even for low dilution rates, leading to six-fold higher protein levels at steady state. The possibility to combine and independently manipulate continuous dialysis and chemostat operation renders our dialysis chemostat a promising technological basis for complex cell-free synthetic biology applications that require enhanced protein synthesis capacity.

synthetic biology↗

A self-regenerating synthetic cell model

Self-regeneration is a fundamental function of all living systems. Here we demonstrate molecular self-regeneration in a synthetic cell model. By implementing a minimal transcription-translation system within microfluidic reactors, the system was able to regenerate essential protein components from DNA templates and sustained synthesis activity for over a day. By mapping genotype-phenotype landscapes combined with computational modeling we found that minimizing resource competition and optimizing resource allocation are both critically important for achieving robust system function. With this understanding, we achieved simultaneous regeneration of multiple proteins by determining the required DNA ratios necessary for sustained self-regeneration. This work introduces a conceptual and experimental framework for the development of a self-replicating synthetic cell.

synthetic biology↗

A simple, robust, and low-cost method to produce the PURE cell-free system

We demonstrate a simple, robust, and low-cost method for producing the PURE cell-free transcription-translation system. Our OnePot PURE system achieved a protein synthesis yield of 156 {micro}g/mL at a cost of 0.09 USD/{micro}L, leading to a 14-fold improvement in cost normalized protein synthesis yield over existing PURE systems. The OnePot method makes the PURE system easy to generate and allows it to be readily optimized and modified.

synthetic biology↗