Biology subjects

Weck, J. M.

Publications and source records attributed to Weck, J. M..

4 recordsLinked to original sources

bioRxiv2025

Effects of DNA Origami-Based Nanoagent Design on Apoptosis Induction in a Large 3D Spheroid Model

The extrinsic activation of programmed cell death by FasR/CD95 is a promising minimally invasive strategy for cancer treatment. This can be leveraged using high-precision nanoscale therapeutics: Utilizing DNA origami for precise Fas ligand (FasL) presentation resulted in over 100 times more potent apoptosis induction in single cells. However, treating large, solid tumors poses challenges for DNA origami-based therapeutics, including drug distribution and altered cellular behavior. Here, we addressed these challenges using a 3D spheroid model. First, we assessed DNA origamis ability to penetrate tumor tissue, finding that penetration is influenced by the DNA origami size rather its structural flexibility. Second, we evaluated the apoptosis induction efficacy by DNA origami-FasL nanoagents within the spheroid model. The most potent nanoagents were able to completely eradicate all cells in the spheroid. Results indicated that apoptosis induction depended strongly on FasL attachment strategy rather than DNA origami design. Notably, only a rigid neutravidin linker for FasL attachment, rather than a flexible dsDNA linker, halted spheroid growth and fully eradicated all cancer cells. This study offers critical insights into designing DNA-based therapeutics for complex cellular environments and significantly advances DNA origami nanotherapeutic development, highlighting the impact of nanoagent design on cell fate decisions.

bioengineering↗

bioRxiv2024

High yield purification of an Isoleucine zipper modified CD95 Ligand with either biotin or DNA-oligomer binding domain for efficient Cell Apoptosis Induction

BackgroundCluster of differentiation 95 (CD95/Fas/Apo1) as part of the Tumor-necrosis factor (TNF) receptor family is a prototypic trigger of the extrinsic apoptotic pathway and its activation by the trimeric ligand CD95L is of high interest for anticancer therapy. However, CD95L, when presented in solution, exhibits a low efficiency to induce apoptosis signaling in human cells. ResultsHere, we design a recombinant CD95L exhibiting an isoleucine zipper (IZ) motif at the N-terminus for stabilization of the trimerized CD95L and demonstrate its high apoptosis induction efficiency. A cysteine amino acid fused behind the IZ is further used as a versatile coupling site for bionanotechnological applications or for the development of biomedical assays. A fast, cheap, and high-yield production of CD95L via the HEK293T secretory expression system is presented, along with CD95L affinity purification and functionalization. We verified the biological activity of the purified protein and identified a stabilized trimeric CD95L structure as the most potent inducer of apoptosis signaling. ConclusionsThe workflow and the findings reported here will streamline a wide array of future low- or high-throughput TNF-ligand screens, and their modification towards improving apoptosis induction efficiency and anticancer therapy.

cell biology↗

bioRxiv2023

Fully addressable, designer superstructures assembled from a single modular DNA origami

Intricate self-organization is essential in many biological processes, underpinning vital functions and interactions. In an effort to mimic such processes, synthetic biology aims to engineer dynamic structures with controllable functions using nanotechnological tools. A key requirement of engineered building blocks is the ability to assemble and disassemble hierarchically with precision. Using the DNA origami technique, we here present the moDON, a modular DNA origami nanostructure, which is capable of assembling into almost 20 000 diverse monomers, forming complex and controlled superstructures in three dimensions. While shape and addressability of DNA origami are nearly arbitrary, its overall size is limited by the scaffold size. Previous methods of extending the size of DNA origami (e.g. hierarchical assembly, modified scaffolds, etc.), either led to loss over control of shape and addressability beyond monomers or to proportionally increased cost and design effort. With the moDON we were able to overcome both issues. The modular design combines xy- and z-plane assembly methods, enabling the construction of finite and periodic structures beyond 1 GDa. We demonstrate xy-z orthogonality, by enabling controlled selective or parallel assembly and disassembly via distinct orthogonal triggers. The kinetic profile of assembly and disassembly aligns with biological time scales, paving the way for applications in dynamic nanomachinery and advanced biomaterials. Finally, we showcase the conjugation of gold nanoparticles to specific positions within superstructures, underscoring the efficacy of this approach for creating intricate and orthogonal nanoscale architectures with preserved site-specific addressability. The moDON thus offers an efficient, cost-effective solution for constructing large, precisely organized, and fully addressable structures with vast potential in synthetic cellular systems design.

biophysics↗

bioRxiv2020

Nanoscale Organization of FasL on DNA Origami as a Versatile Platform to Tune Apoptosis Signaling in Cells

Nanoscale probes with fine-tunable properties are of key interest in cell biology and nanomedicine to elucidate and eventually control signaling processes in cells. A critical, still challenging issue is to conjugate these probes with molecules in a number- and spatially-controlled manner. Here, DNA origami-based nanoagents as nanometer precise scaffolds presenting Fas ligand (FasL) in well-defined arrangements to cells are reported. These nanoagents activate receptor molecules in the plasma membrane initiating apoptosis signaling in cells. Signaling for apoptosis depends sensitively on FasL geometry: fastest time-to-death kinetics are obtained for FasL nanoagents representing predicted structure models of hexagonal receptor ordering with 10 nm inter-molecular spacing. Slower kinetics are observed for one to two FasL on DNA origami or FasL coupled with higher flexibility. Nanoagents with FasL arranged in hexagons with small (5 nm) and large (30 nm) spacing impede signal transduction. Moreover, for predicted hexagonal FasL nanoagents, signaling efficiency is faster and 100× higher compared to naturally occurring soluble FasL. Incubation of the FasL-origami nanoagent in solution exhibited an EC50 value of only 90 pM. These studies present DNA origami as versatile signaling platforms to probe the significance of molecular number and nanoscale ordering for signal initiation in cells.Competing Interest StatementThe authors have declared no competing interest.View Full Text

biophysics↗