Mucin-Inspired Polymeric Fibers for Herpes Simplex Virus Type 1 Inhibition

Mucus lines the epithelial cells at the biological interface and is the first line of defense against multiple viral infections. Mucins, the gel-forming components of mucus, are high molecular weight glycoproteins and crucial for preventing infections by binding pathogens. Consequently, mimicking mucins is a promising strategy for new synthetic virus inhibitors. In this work, synthetic mucin-inspired polymers (MIPs) as potential inhibitors of herpes simplex virus 1 (HSV-1) are investigated. By using a telechelic reversible addition-fragmentation chain-transfer (RAFT) polymerization technique, a new dendronized polysulfate p(G1AAm-OSO3)PDS with an amide-backbone similar to the native mucin glycoproteins is synthesized. p(G1AAm-OSO3)PDS shows mucin-like elongated fiber structure, as revealed in cryo-electron microscopy (cryo-EM) imaging, and its HSV-1 inhibition activity together with its previously reported methacrylate analogue p(G1MA-OSO3)PDS is tested. Both of the sulfated MIPs show strong HSV-1 inhibition in plaque reduction assays with IC50 values in lower nanomolar range ( 1.0 mg mL−1) with lower anticoagulant activity than heparin. In addition, the prophylactic and therapeutic activity of both MIPs is assessed in pre- and post-infection inhibition assays and clearly visualize their high potential for application using fluorescent microscopy imaging of infected cells

Mucin-Inspired Single-Chain Polymer (MIP) Fibers as Potent SARS-CoV-2 Inhibitors

Mucins are the key component of the defensive mucus barrier. They are extended fibers of very high molecular weight with diverse biological functions depending strongly on their specific structural parameters. Here, we present a mucin-inspired nanostructure, produced via a synthetic methodology to prepare methacrylate-based dendronized polysulfates (MIP-1) on a multi gram scale with relatively high molecular weight (MW = 450 kDa) and thiol end-functionalized mucin-inspired polymer (MIP) via RAFT polymerization. Cryo-electron tomography (Cryo-ET) analysis of MIP-1 confirmed a mucin-mimetic wormlike single-chain fiber structure (length = 144.5 ± 59.4 nm) in aqueous solution. This biocompatible fiber showed promising activity against SARS-CoV-2 and its mutant strain, with a remarkable low half maximal (IC50) inhibitory concentration (IC50 = 10.0 nM). Additionally, we investigate the impact of fiber length on SARS-CoV-2 inhibition by testing other functional polymers (MIPs) of varying fiber lengths

Mucus-Inspired Self-Healing Hydrogels: A Protective Barrier for Cells against Viral Infection

Mucus is a dynamic biological hydrogel, composed primarily of the glycoprotein mucin, exhibits unique biophysical properties and forms a barrier protecting cells against a broad-spectrum of viruses. Here, this work develops a polyglycerol sulfate-based dendronized mucin-inspired copolymer (MICP-1) with ≈10% repeating units of activated disulfide as cross-linking sites. Cryo-electron microscopy (Cryo-EM) analysis of MICP-1 reveals an elongated single-chain fiber morphology. MICP-1 shows potential inhibitory activity against many viruses such as herpes simplex virus 1 (HSV-1) and SARS-CoV-2 (including variants such as Delta and Omicron). MICP-1 produces hydrogels with viscoelastic properties similar to healthy human sputum and with tuneable microstructures using linear and branched polyethylene glycol-thiol (PEG-thiol) as cross-linkers. Single particle tracking microrheology, electron paramagnetic resonance (EPR) and cryo-scanning electron microscopy (Cryo-SEM) are used to characterize the network structures. The synthesized hydrogels exhibit self-healing properties, along with viscoelastic properties that are tuneable through reduction. A transwell assay is used to investigate the hydrogel's protective properties against viral infection against HSV-1. Live-cell microscopy confirms that these hydrogels can protect underlying cells from infection by trapping the virus, due to both network morphology and anionic multivalent effects. Overall, this novel mucin-inspired copolymer generates mucus-mimetic hydrogels on a multi-gram scale. These hydrogels can be used as models for disulfide-rich airway mucus research, and as biomaterials

Methodological approaches for studying the microbial ecology of drinking water distribution systems

The study of the microbial ecology of drinking water distribution systems (DWDS) has traditionally been based on culturing organisms from bulk water samples. The development and application of molecular methods has supplied new tools for examining the microbial diversity and activity of environmental samples, yielding new insights into the microbial community and its diversity within these engineered ecosystems. In this review, the currently available methods and emerging approaches for characterising microbial communities, including both planktonic and biofilm ways of life, are critically evaluated. The study of biofilms is considered particularly important as it plays a critical role in the processes and interactions occurring at the pipe wall and bulk water interface. The advantages, limitations and usefulness of methods that can be used to detect and assess microbial abundance, community composition and function are discussed in a DWDS context. This review will assist hydraulic engineers and microbial ecologists in choosing the most appropriate tools to assess drinking water microbiology and related aspects

Mucus-Inspired Self-Healing Hydrogels: A Protective Barrier for Cells against Viral Infection

Mucus is a dynamic biological hydrogel, composed primarily of the glycoprotein mucin, exhibits unique biophysical properties and forms a barrier protecting cells against a broad spectrum of viruses. Here we developed a polyglycerol sulfate-based dendronized mucin-inspired copolymer (MICP-1) with ~10 % repeating units of activated disulfide as cross-linking sites. Cryo-EM analysis of MICP-1 reveals an elongated single-chain fiber morphology. MICP-1 shows potential inhibitory activity against many viruses such as HSV-1 and SARS-CoV-2 (including variants such as Delta and Omicron). MICP-1 produces hydrogels with viscoelastic properties similar to healthy human sputum and with tuneable microstructures using linear and branched PEG-thiol as cross-linkers. Single particle tracking microrheology, EPR and Cryo-SEM were used to characterize the network structures. The synthesized hydrogels exhibit self-healing properties, along with viscoelastic properties that are tuneable through reduction. a transwell assay was used to investigate the hydrogel’s protective properties against viral infection against HSV-1. Live-cell microscopy confirmed that these hydrogels can protect underlying cells from infection by trapping the virus, due to both network morphology and anionic multivalent effects. Overall, our novel mucin-inspired copolymer generates mucus-mimetic hydrogels on a multi-gram scale. These hydrogels can be used as a models for disulfide-rich airway mucus research, and as biomaterials