Porcine gastric mucin binds to recombinant norovirus particles and competitively inhibits their binding to histo-blood group antigens and Caco-2 cells.
OBJECTIVE
To determine if human noroviruses (NV) bind to histo-blood group antigens (HBGA) from pig gastric mucosa.


RESULTS
An assay was developed to measure the inhibition of binding of recombinant norovirus-like particles (rNVLP) to HBGA in human saliva by porcine gastric mucin (PGM). The binding of rNVLP to HBGA could be inhibited by PGM in a dose-dependent pattern. Also, rNVLP could be captured effectively by PGM coated directly on plates and was detected by binding of polyclonal antibodies against rNVLP. Similarly, the binding of rNVLP to PGM could be inhibited effectively by HBGA in human saliva, and by Lewis b and Lewis d synthetic oligosaccharides (OS), but not inhibited effectively by an H3 OS or by purified bovine submaxillary gland mucin. Preincubation of rNVLPs with PGM completely inhibited their binding to human Caco-2 cells.


CONCLUSIONS
PGM binds effectively to rNVLPs and competitively inhibits rNVLPs binding to human HBGA and Caco-2 cells.


CONCLUSIONS
This is the first report of the binding of glycoproteins from animal gastric mucosa to human NVs. This study highlights the importance of further characterizing the NV incidence and infections in nonhuman animal hosts and the possibility that NV is a zoonotic disease.
Tian
P
P
Produce Safety and Microbiology Research Unit, Western Regional Research Center, Agricultural Research Service, United States Department of Agriculture, Albany, CA 94710-1105, USA. ptian@pw.usda.gov
Brandl
M
M
Mandrell
R
R
D000818:Animals; D001667:Binding, Competitive; D001789:Blood Group Antigens / Q000378:metabolism*; D018938:Caco-2 Cells; D005752:Gastric Mucins / Q000378:metabolism*; D006801:Humans; D018613:Microscopy, Confocal; D029322:Norovirus / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity; D011995:Recombination, Genetic; D012463:Saliva; D013552:Swine; D014771:Virion / Q000235:genetics / Q000378:metabolism*
D001789:Blood Group Antigens; D005752:Gastric Mucins