Biology subjects

Huebner, W.

Publications and source records attributed to Huebner, W..

4 recordsLinked to original sources

bioRxiv2026

The immunogenic 33-mer gliadin peptide attenuates flagellin-induced TLR5/NF-κB signaling

Wheat gluten is the main trigger of gluten-related disorders such as celiac disease, in which the proteolysis-resistant, 33-mer peptide is a key immunodominant factor. It has been reported that the 33-mer forms oligomers and thin-plate superstructures that accumulate in the Caco-2 intestinal epithelial cell line, although their biological effects remain only partially understood. Here, we screened the effects of these nanostructures on Toll-like receptors in Caco-2 cells to investigate their effect on the early innate immune response. Our findings showed a specific upregulation of TLR5 mRNA in response to 33-mer gliadin superstructures, although no inflammatory response was detected based on CXCL1 and CXCL8 levels. Moreover, immunofluorescence analysis revealed partial co-localization with TLR5. We further found that the 33-mer superstructures attenuate flagellin-induced TLR5/NF{kappa}B signaling in reporter cells, similar to a blocking anti-hTLR5-IgA2 antibody. Molecular docking suggested that the 33-mer peptide occupies the concave region of TLR5 as well as 54% of the TLR5-TLR5 dimerization interface. The interference with the TLR5 dimerization domain could explain the experimental attenuation of flagellin-mediated TLR5 activation. Given that TLR5 contributes not only to inflammation but also to intestinal homeostasis, our findings suggest that the formation of 33-mer nanostructures upon its accumulation may increase the local concentration of 33-mer, interfering with TLR5-mediated mucosal immune responses. These findings provide a rationale for investigating the role of TLR5 and 33-mer aggregates in clinical samples from patients with celiac disease and other gluten-related disorders.

immunology↗

bioRxiv2025

Peroxisome protein import deficiency causes heart failure in mouse and human

Peroxisomes are ubiquitous cellular organelles with potentially vital roles in lipid and reactive oxygen metabolism. The metabolic demands of the heart are substantial; however, the contribution of peroxisomes to cardiac development, health, and their role in heart failure (HF) remain largely unexplored. We developed and examined a mouse and an engineered human myocardium (EHM) model with a deficiency in cardiac peroxisome biogenesis to investigate the role of peroxisomes in cardiac function and pathology. In the EHM, loss of peroxisome protein import and subsequent peroxisomal metabolic impairment trigger mitochondrial damage and compromise cellular respiration and energy production. Peroxisome dysfunction results in incoherent electrical conduction, defective Ca2+-handling, and ultimately presentation of a HF phenotype with pathological force generation. These phenotypes are mirrored in an orthogonal murine model system with defective cardiac peroxisome biogenesis. Preload-dependent deficits in force generation due to insufficient energy supply are eventually fatal. Thus, peroxisomes play an important role in sustaining normal heart operations. Vice versa, peroxisome maintenance is compromised in pressure overload-induced HF, establishing peroxisomes as potential modulators of pathology and targets of therapy.

cell biology↗

bioRxiv2023

A missense mutation (C667F) in beta-dystroglycan results in reduced dystroglycan protein levels leading to myopathy and destabilization of the blood-brain and blood-retinal barrier protein network

Dystroglycan (DG) is a glycoprotein and extracellular matrix receptor consisting of an -DG and a {beta}-DG subunit encoded by the gene DAG1. A homozygous missense mutation (c.2006G>T), resulting in an amino acid substitution (p.Cys669Phe) in the extracellular domain of {beta}-DG, causes severe Muscle-Eye-Brain disease with multicystic leukodystrophy. To investigate the mechanisms underlying the severe human pathology, we generated a mouse model of this primary dystroglycanopathy. We find that homozygous mutant mice show no obvious abnormalities during development and reach mature adulthood. However, - and {beta}-DG protein levels are significantly downregulated in muscle and brain of homozygous mutant mice. The mutant mice show a form of myopathy with late-onset and not fully penetrant histopathological changes in skeletal muscle and are impaired in their performance on an activity wheel. The brain and eyes of the homozygous mutant mice appear to be structurally normal, but the localization of mutant {beta}-DG is altered in the glial perivascular endfeet (PVE) at the blood-brain- and blood-retina barrier resulting in a perturbed protein composition in the PVE. In conclusion, the mouse model of the C669F {beta}-DG mutation does not seem to recapitulate the severe developmental phenotypes observed in human patients but represents a novel and highly valuable tool to study the impact of {beta}-DG functional changes at the molecular level and to gain insight into the pathogenesis of primary dystroglycanopathies.

pathology↗

bioRxiv2018

A cost-effective approach to Super-resolution Optical Fluctuation (SOFI) microscopy using an industry-grade CMOS camera

Super-resolution (SR) fluorescence microscopy, especially at high speeds, is typically carried out on high-performance research microscopes. The substantial cost of such equipment, combined with the limited distribution of such instruments in imaging facilities, have complicated access to super-resolution imaging for research groups in the biosciences. In this work we promote the accessibility of Super-resolution Optical Fluctuation Imaging (SOFI) to the scientific community by demonstrating its flexibility in terms of the minimal required performance of the imaging system. We show that SOFI data can be acquired using a very cost-efficient industrial-grade detector on both a standard research microscope and an entirely home-built wide-field system. This enables more scientists to enter the field of live-cell super-resolution imaging, as it provides access to a robust and fast SR imaging modality at comparatively modest cost.

biophysics↗