title: Saccharomyces cerevisiae-derived HBsAg preparations differ in their attachment to monocytes, immune-suppressive potential, and T-cell immunogenicity.
abstract: Expression of the hepatitis B virus S protein results in the formation of a lipoprotein particle, the hepatitis B surface antigen (HBsAg). Such particles, produced in Saccharomyces cerevisiae, bind to the cell surface of monocytes through interaction with the lipopolysaccharide binding protein and the lipopolysaccharide receptor, CD14. This attachment is suggested to depend on the presence of charged phospholipids in the particles. In addition, such particles interfere with the lipopolysaccharide and interleukin-2-induced activation of monocytes. In the present study, it is reported that of three Saccharomyces cerevisiae-derived HBsAg preparations, two have a reduced capacity to bind to monocytes. A correlation with a reduced potential to inhibit the lipopolysaccharide-induced activation of monocytes and an increased potential to stimulate HBsAg-specific T-cell proliferation is observed. Surprisingly, differences in phospholipid content that might explain these observations, were not detected.
authors.affiliation: Center for Vaccinology, Department of Clinical Biology, Microbiology and Immunology, Ghent University Hospital, Ghent, Belgium. peter.vanlandschoot@rug.ac.be
authors.forename: Peter
authors.initials: P
authors.lastname: Vanlandschoot
authors.forename: Freya
authors.initials: F
authors.lastname: Van Houtte
authors.forename: Frans
authors.initials: F
authors.lastname: Hoek
authors.forename: Rienk
authors.initials: R
authors.lastname: Nieuwland
authors.forename: Geert
authors.initials: G
authors.lastname: Leroux-Roels
mesh_terms: D000818:Animals; D006224:Cricetinae; D004797:Enzyme-Linked Immunosorbent Assay; D006514:Hepatitis B Surface Antigens / Q000235:genetics / Q000276:immunology*; D006801:Humans; D007165:Immunosuppression Therapy; D018950:Lipopolysaccharide Receptors / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology; D008213:Lymphocyte Activation / Q000276:immunology*; D009000:Monocytes / Q000276:immunology*; D010743:Phospholipids / Q000032:analysis; D011994:Recombinant Proteins / Q000276:immunology; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D006514:Hepatitis B Surface Antigens; D018950:Lipopolysaccharide Receptors; D008070:Lipopolysaccharides; D010743:Phospholipids; D011994:Recombinant Proteins