Do viruses use vectors to penetrate mucus barriers?

Polyglycerol-Based Mucus-Inspired Hydrogels

The mucus layer is a hydrogel network that covers mucosal surfaces of the human body. Mucus has important protective properties that are related to its unique rheological properties, which are based on mucins being the main glycoprotein constituents. Mucin macromolecules entangle with one another and form a physical network that is instrumental for many important defense functions. Mucus derived from various human or animal sources is poorly defined and thus not suitable for many application purposes. Herein, a synthetic route is fabricated to afford a library of compositionally defined mucus-inspired hydrogels (MIHs). MIHs are synthesized by thiol oxidation to render disulfide bonds between the crosslinker ethoxylated trimethylolpropane tri(3-mercaptopropionate) (THIOCURE ETTMP 1300) and the linear precursors, dithiolated linear polyglycerol (LPG(SH)₂ ) or polyethylene glycol (PEG(SH)₂ ) of different molecular weights. The mixing ratio of linear polymers versus crosslinker and the length of the linear polymer are varied, thus delivering a library of compositionally defined mucin-inspired constructs. Their viscoelastic properties are determined by frequency sweeps at 25 and 37 °C and compared to the corresponding behavior of native human mucus. Here, MIHs composed of a 10:1 ratio of LPG(SH)₂ and ETTMP 1300 are proved to be the best comparable to human airway mucus rheology.

Neutrophils in viral infection

Neutrophils are the first wave of recruited immune cells to sites of injury or infection and are crucial players in controlling bacterial and fungal infections. Although the role of neutrophils during bacterial or fungal infections is well understood, their impact on antiviral immunity is much less studied. Furthermore, neutrophil function in tumor pathogenesis and cancer treatment has recently received much attention, particularly within the context of oncolytic virus infection where neutrophils produce antitumor cytokines and enhance oncolysis. In this review, multiple functions of neutrophils in viral infections and immunity are discussed. Understanding the role of neutrophils during viral infection may provide insight into the pathogenesis of virus infections and the outcome of virus-based therapies.

Detection and quantification of human herpes viruses types 4-6 in sperm samples of patients with fertility disorders and chronic inflammatory urogenital tract diseases

Acute and chronic infections of the seminal tract are among the most common causes of male infertility. As at least half of male infertility cases are classified as idiopathic, some of these cases might be attributed to asymptomatic infection. The detection and quantification of Epstein-Barr virus (EBV), cytomegalovirus (CMV) and human herpes virus type 6 (HHV-6) DNA in semen samples were performed. A total of 232 patients were divided into five groups: (i) infertile men with varicocoele; (ii) men with idiopathic infertility; (iii) infertile men with chronic inflammatory urogenital tract diseases (IUTD); (iv) fertile men with IUTD and (v) men whose partners had a history of pregnancy loss. In the study population, the prevalence of viral DNA was 17.7, 3.4% for EBV, 5.2% for CMV, 6.5% for HHV-6, 0.43% for EBV + CMV, 0.87% for EBV + HHV-6 and 1.3% for CMV + HHV-6. The median viral loads for EBV, CMV and HHV-6 were 500, 2250 and 250 copies/mL respectively. Of the sperm cell fractions, derived from infected samples 87.5% contained viral DNA. No association between EBV and fertility disorders or IUTD was found. CMV detection was much higher in the group of patients with infertility and concomitant IUTD compared with the other groups combined (18.5% vs. 5.4%, p = 0.03) and associated with reduced sperm cell count (39.5 × 10(6) /mL vs. 72.5 × 10(6) /mL, p = 0.036). Immunostaining of spermatozoa from infected samples and in vitro-infected cells detected CMV in sperm heads, tails and connecting pieces and revealed attachment to sperm membrane and intracellular localization. HHV-6 was the more common in fertile men with chronic IUTD than in the other groups combined (19% vs. 6.3%, p = 0.018) and had no effect on sperm parameters. The results suggest that both CMV and HHV-6 may contribute to the aetiology of IUTD and, moreover, CMV-associated IUTD can lead to male sterility.