The effect of proteolytic enzymes and pH on GII.4 norovirus, during both interactions and non-interaction with Histo-Blood Group Antigens

• Published in: Scientific reports Vol. 10; no. 1; p. 17926
• Main Authors: Chassaing, Manon, Robin, Maëlle, Loutreul, Julie, Majou, Didier, Belliot, Gaël, de Rougemont, Alexis, Boudaud, Nicolas, Gantzer, Christophe
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 21.10.2020; Nature Publishing Group
• Subjects: 631/326/596/2557; 692/4020/1503/1501; Antigens; Blood Group Antigens - metabolism; Blood Group Antigens - physiology; Blood groups; Caliciviridae Infections - virology; Capsid - drug effects; Capsids; Chymotrypsin; Chymotrypsin - pharmacology; Digestive system; Dose-Response Relationship, Drug; Enzymes; Food and Nutrition; Gastroenteritis; Gastroenteritis - virology; Genomes; Humanities and Social Sciences; Humans; Hydrogen-Ion Concentration; Life Sciences; multidisciplinary; Norovirus - drug effects; Norovirus - genetics; Norovirus - metabolism; Norovirus - pathogenicity; Pepsin; Pepsin A - pharmacology; Peptide Hydrolases - pharmacology; pH effects; Proteolysis; Proteolytic enzymes; Ribonuclease; Science; Science (multidisciplinary); Trypsin; Trypsin - pharmacology; Virus Attachment - drug effects; Virus-like particles; Gastroenteritis; Virus-host interactions
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-020-74728-z

Human noroviruses (HuNoVs) are the leading cause of acute gastroenteritis worldwide. Histo-Blood Groups Antigens (HBGAs) have been described as attachment factors, promoting HuNoV infection. However, their role has not yet been elucidated. This study aims to evaluate the ability of HBGAs to protect HuNoVs against various factors naturally found in the human digestive system. The effects of acid pH and proteolytic enzymes (pepsin, trypsin, and chymotrypsin) on GII.4 virus-like particles (VLPs) and GII.4 HuNoVs were studied, both during interactions and non-interaction with HBGAs. The results showed that GII.4 VLPs and GII.4 HuNoVs behaved differently following the treatments. GII.4 VLPs were disrupted at a pH of less than 2.0 and in the presence of proteolytic enzymes (1,500 units/mL pepsin, 100 mg/mL trypsin, and 100 mg/mL chymotrypsin). VLPs were also partially damaged by lower concentrations of trypsin and chymotrypsin (0.1 mg/mL). Conversely, the capsids of GII.4 HuNoVs were not compromised by such treatments, since their genomes were not accessible to RNase. HBGAs were found to offer GII.4 VLPs no protection against an acid pH or proteolytic enzymes.