TITLE:
Dietary sugars inhibit biologic functions of the pattern recognition molecule, mannose-binding lectin
AUTHORS:
Kazue Takahashi, Wei-Chuan Chang, Patience Moyo, Mitchell R. White, Parool Meelu, Anamika Verma, Gregory L. Stahl, Kevan L. Hartshorn, Vijay Yajnik
KEYWORDS:
Mannose-Binding Lectin; Fructose; Influenza A Virus; Staphylococcus Aureus; Complement; Coagulation
JOURNAL NAME:
Open Journal of Immunology,
Vol.1 No.2,
September
30,
2011
ABSTRACT: Mannose-binding lectin (MBL), a mammalian lectin, is a pattern recognition molecule of the innate immune system and recognizes carbo-hydrates that are exposed on pathogens. In this study, we observed that fructose down regu-lates MBL-mediated innate immune mechanisms against both influenza A virus (IAV) and Staphy-lococcus aureus. These mechanisms include the lectin complement pathway and coagulation enzyme-like activities on both pathogens. Fur-thermore, fructose also reduces MBL-mediated phagocytosis of S. aureus and IAV and MBL- mediated IAV infection to epithelial cells. In contrast, sucrose inhibits MBL-mediated im-mune mechanisms against S. aureus but not IAV. Together, our studies show that dietary sugars, in particular fructose, negatively regulate the innate immunity against viral and bacterial pathogens.