Biology subjects

Fuerst, T.

Publications and source records attributed to Fuerst, T..

3 recordsLinked to original sources

bioRxiv2025

Enhanced Production of HCV E1E2 Subunit Vaccine Candidates via Protein-Protein Interaction Identification in Glycoengineered CHO cells

Hepatitis C Virus (HCV) is a bloodborne virus that affects 57 million people globally with infections that can often go unnoticed, and it is the leading cause of chronic liver disease and cancer. Thus, development of an HCV vaccine is a major medical and public health concern. While prior work has developed secreted E1E2 (sE1E2) protein vaccine candidates, efforts to express it recombinantly in Chinese hamster ovary (CHO) cells have resulted in very low titers. To address this challenge, here we employed a multi-omics approach to identify protein interactors that enhance the secretion of sE1E2. By detecting Protein-Protein Interactions (PPIs) using Biotinylation by Antibody Recognition (BAR) and integrating the data with RNA-Seq, we identified proteins within the secretory pathway that interact with sE1E2 and validated their impact by overexpressing the interacting proteins. Among these, CUL4A and YWHAH enhanced sE1E2 secretion in glycoengineered CHO (geCHO) cells. The integration of omics techniques and genetic engineering in this study provides valuable insights into improving protein secretion in CHO cells, paving the way for the development of more affordable and accessible biotherapeutics.

systems biology↗

bioRxiv2025

Native-like soluble E1E2 glycoprotein heterodimers on self-assembling protein nanoparticles for hepatitis C virus vaccine design

Hepatitis C virus (HCV) is a leading cause of chronic liver disease, cirrhosis, and hepatocellular carcinoma worldwide. E1E2-based HCV vaccine development has been hindered by the challenge of producing a soluble E1E2 (sE1E2) antigen that faithfully recapitulates the native glycoprotein heterodimer found on virions. Based on available cryo-electron microscopy (cryo-EM) structures, we rationally engineered sE1E2 for genotype 1a H77 by truncating the E1 and E2 stems (Cut1), removing a putative fusion peptide (pFP)-containing region in E1 (Cut2), and stabilizing the E1-E2 interface with diverse heterodimeric scaffolds. All H77 sE1E2.Cut1+2 scaffolds showed native-like E1-E2 association and robust binding to the broadly neutralizing antibody (bNAb) AR4A. A genotype 1a HCV-1 sE1E2.Cut1+2 variant scaffolded by a modified SpyTag/SpyCatcher (SPY{Delta}N) was selected for in vitro, structural, and immunogenic characterization. The structure of this sE1E2 scaffold in complex with bNAbs was analyzed by cryo-EM and negative-stain EM (nsEM), with an nsEM-based approach developed for antibody epitope mapping. HCV-1 sE1E2.Cut1+2.SPY{Delta}N was displayed on self-assembling protein nanoparticles (SApNPs) to enhance immunogenicity. HCV-1 sE1E2.Cut1+2.SPY{Delta}N heterodimer and SApNPs with wildtype and modified glycans were tested in mice, revealing the beneficial effects of multivalent display and oligomannose enrichment. Our study provides a rigorous foundation for next-generation HCV vaccine development. ONE-SENTENCE SUMMARYRational design, characterization, and in vivo assessment of HCV soluble E1E2 heterodimer and nanoparticles will inform vaccine development.

microbiology↗

bioRxiv2025

Expression and Characterization of SARS-CoV-2 Spike Protein in Thermothelomyces heterothallica C1

The COVID-19 pandemic demonstrated a pressing need for rapid, adaptive, and scalable manufacturing of vaccines and reagents. With the transition into an endemic disease and rising threats of other emerging pandemics, production of these biologicals requires a stable and sustainable supply chain and accessible distribution methods. In this study, we demonstrate the strength of an engineered filamentous fungal platform, Thermothelomyces heterothallica C1, for high volumetric productivity of the full-length spike glycoprotein. Spike protein produced in this system is highly thermostable and immunization of mice with spike made in C1 or mammalian platforms resulted in a similar humoral response. Additionally, it was shown that the native N-glycan profile can be redecorated with complex sialylated structures, if necessary, resulting in a more human-like glycan profile, without impacting binding characteristics as shown experimentally and in simulations. Through extensive physicochemical analysis, the C1 produced spike performs similarly to spike proteins produced in other commercially available systems. The data presented is evidence that C1 can be a strong platform for production of complex glycosylated recombinant proteins such as subunit antigen vaccines.

bioengineering↗