Systematic evaluation of fluorination as modification for peptide-based fusion inhibitors against HIV-1 infection

With the emergence of novel viruses, the development of new antivirals is more urgent than ever. A key step in human immunodeficiency virus type 1 (HIV-1) infection is six-helix bundle formation within the envelope protein subunit gp41. Selective disruption of bundle formation by peptides has been shown to be effective; however, these drugs, exemplified by T20, are prone to rapid clearance from the patient. The incorporation of non-natural amino acids is known to improve these pharmacokinetic properties. Here, we evaluate a peptide inhibitor in which a critical Ile residue is replaced by fluorinated analogues. We characterized the influence of the fluorinated analogues on the biophysical properties of the peptide. Furthermore, we show that the fluorinated peptides can block HIV-1 infection of target cells at nanomolar levels. These findings demonstrate that fluorinated amino acids are appropriate tools for the development of novel peptide therapeutics

First sequence-confirmed case of infection with the new influenza A(H1N1) strain in Germany

Here, we report on the first sequence-confirmed case of infection with the new influenza A(H1N1) virus in Germany. Two direct contacts of the patient were laboratory-confirmed as cases and demonstrate a chain of direct human-to-human transmission

Efficacy of a Mouthwash Containing CHX and CPC in SARS-CoV-2–Positive Patients: A Randomized Controlled Clinical Trial

Soon after the outbreak of the coronavirus disease 2019 (COVID-19) pandemic, preprocedural mouthwashes were recommended for temporarily reducing intraoral viral load and infectivity of individuals potentially infected with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in order to protect medical personnel. Particularly, the antiseptic cetylpyridinium chloride (CPC) has shown virucidal effects against SARS-CoV-2 in vitro. Therefore, the aim of this randomized controlled clinical trial was to investigate the efficacy of a commercially available mouthwash containing CPC and chlorhexidine digluconate (CHX) at 0.05% each in SARS-CoV-2–positive patients as compared to a placebo mouthwash. Sixty-one patients who tested positive for SARS-CoV-2 with onset of symptoms within the last 72 h were included in this study. Oropharyngeal specimens were taken at baseline, whereupon patients had to gargle mouth and throat with 20 mL test or placebo (0.9% NaCl) mouthwash for 60 s. After 30 min, further oropharyngeal specimens were collected. Viral load was analyzed by quantitative reverse transcriptase polymerase chain reaction, and infectivity of oropharyngeal specimens was analyzed by virus rescue in cell culture and quantified via determination of tissue culture infectious doses 50% (TCID50). Data were analyzed nonparametrically (α = 0.05). Viral load slightly but significantly decreased upon gargling in the test group (P = 0.0435) but not in the placebo group. Viral infectivity as measured by TCID50 also significantly decreased in the test group (P = 0.0313), whereas there was no significant effect but a trend in the placebo group. Furthermore, it was found that the specimens from patients with a vaccine booster exhibited significantly lower infectivity at baseline as compared to those without vaccine booster (P = 0.0231). This study indicates that a preprocedural mouthwash containing CPC and CHX could slightly but significantly reduce the viral load and infectivity in SARS-CoV-2–positive patients. Further studies are needed to corroborate these results and investigate whether the observed reductions in viral load and infectivity could translate into clinically useful effects in reducing COVID-19 transmission (German Clinical Trials Register DRKS00027812)

Comparison of the oncolytic activity of a replication‐competent and a replication‐deficient herpes simplex virus 1

In 2015, the oncolytic herpes simplex virus 1 (HSV-1) T-VEC (talimogene laherparepvec) was approved for intratumoral injection in non-resectable malignant melanoma. To determine whether viral replication is required for oncolytic activity, we compared replication-deficient HSV-1 d106S with replication-competent T-VEC. High infectious doses of HSV-1 d106S killed melanoma (n = 10), head-and-neck squamous cell carcinoma (n = 11), and chondrosarcoma cell lines (n = 2) significantly faster than T-VEC as measured by MTT metabolic activity, while low doses of T-VEC were more effective over time. HSV-1 d106S and, to a lesser extent T-VEC, triggered caspase-dependent early apoptosis as shown by pan-caspase inhibition and specific induction of caspases 3/7, 8, and 9. HSV-1 d106S induced a higher ratio of apoptosis-inducing infected cell protein (ICP) 0 to apoptosis-blocking ICP6 than T-VEC. T-VEC was oncolytic for an extended period of time as viral replication continued, which could be partially blocked by the antiviral drug aciclovir. High doses of T-VEC, but not HSV-1 d106S, increased interferon-β mRNA as part of the intrinsic immune response. When markers of immunogenic cell death were assessed, ATP was released more efficiently in the context of T-VEC than HSV-1 d106S infection, whereas HMGB1 was induced comparatively well. Overall, the early oncolytic effect on three different tumour entities was stronger with the non-replicative strain, while the replication-competent virus elicited a stronger innate immune response and more pronounced immunogenic cell death

NÖ Modell einer gesamtökologischen Beurteilung von Abwasserentsorgungskonzepten Möglichkeiten der Umsetzung

Durch die Verlagerung des Schwerpunktes der Abwasserreinigung in den ländlichen Raum und durch geänderte gesetzliche Vorgaben wurde eine eingehende Betrachtung der Immissionssituation und der ökologischen Rahmenbedingungen erforderlich. Sowohl der „Leitfaden für Niederösterreich“ als auch die „Gesamtökologische Beurteilung“ befaßt sich mit den bei der Abwasserreinigung und Abwassereinleitung in Gewässer relevanten ökologischen Faktoren und gibt Anleitungen für die Vorgangsweise in der Praxis. Anhand der beiden Pilotgemeinden Obritzberg-Rust und Leiben wurde der Versuch einer weitgehenden ökologischen Überprüfung unternommen, wobei als Ziel eine Reihung möglicher Entsorgungsvarianten nach ihrer ökologischen Verträglichkeit angestrebt wurde (Verfasser A. Schwaller). Schließlich werden die Möglichkeiten der Umsetzung diskutiert, wobei als Grundlage die derzeitig geltenden Voraussetzungen für eine öffentliche Förderung durch Bund und Land Niederösterreich dienen. Der Verfasser (K.J. Rohrhofer) stellt aus seiner Sicht Möglichkeiten für eine „neue Vorgangsweise“ dar.1301351814

Systematic Evaluation of Fluorination as Modification for Peptide Based Fusion Inhibitors against HIV 1 Infection

With the emergence of novel viruses, the development of new antivirals is more urgent than ever. A key step in human immunodeficiency virus type 1 (HIV-1) infection is six-helix bundle formation within the envelope protein subunit gp41. Selective disruption of bundle formation by peptides has been shown to be effective; however, these drugs, exemplified by T20, are prone to rapid clearance from the patient. The incorporation of non-natural amino acids is known to improve these pharmacokinetic properties. Here, we evaluate a peptide inhibitor in which a critical Ile residue is replaced by fluorinated analogues. We characterized the influence of the fluorinated analogues on the biophysical properties of the peptide. Furthermore, we show that the fluorinated peptides can block HIV-1 infection of target cells at nanomolar levels. These findings demonstrate that fluorinated amino acids are appropriate tools for the development of novel peptide therapeutics

Nutrients / Immune Effects of the Nitrated Food Allergen Beta-Lactoglobulin in an Experimental Food Allergy Model

Food proteins may get nitrated by various exogenous or endogenous mechanisms. As individuals might get recurrently exposed to nitrated proteins via daily diet, we aimed to investigate the effect of repeatedly ingested nitrated food proteins on the subsequent immune response in non-allergic and allergic mice using the milk allergen beta-lactoglobulin (BLG) as model food protein in a mouse model. Evaluating the presence of nitrated proteins in food, we could detect 3-nitrotyrosine (3-NT) in extracts of different foods and in stomach content extracts of non-allergic mice under physiological conditions. Chemically nitrated BLG (BLGn) exhibited enhanced susceptibility to degradation in simulated gastric fluid experiments compared to untreated BLG (BLGu). Gavage of BLGn to non-allergic animals increased interferon- and interleukin-10 release of stimulated spleen cells and led to the formation of BLG-specific serum IgA. Allergic mice receiving three oral gavages of BLGn had higher levels of mouse mast cell protease-1 (mMCP-1) compared to allergic mice receiving BLGu. Regardless of the preceding immune status, non-allergic or allergic, repeatedly ingested nitrated food proteins seem to considerably influence the subsequent immune response.(VLID)458847