Humoral immune response to a 200-kDa glycoprotein antigen of Saccharomyces cerevisiae is common in man

Abstract

According to Heelan et al. patients suffering from Crohn’s disease (CD) produce antibodies against a cell wall associated glycoprotein antigen gp200 of the yeast Saccharomyces cerevisiae, while healthy people do not. Here the authors show, that antibodies against this glycoprotein gp200 can also be detected in the sera of healthy humans. The intensity of the antibody titer which is measured by immunoblot experiments is independent from the state of health. The Saccharomyces cerevisiae specific gp200 is a highly glycosylated protein localized not only in the cell wall but also accumulated in the culture medium. Some of the tested sera from CD patients, as well as from healthy adults, also reacted with a 120-kDa glycoprotein which is to be found in preparations containing secreted proteins. Because the binding of antibodies is greatly reduced by periodate treatment of gp200 and by the 120-kDa polypeptide, it is very likely that their carbohydrate moieties are the antigenic determinants against which the specific human antibodies are directed. The human humoral immune response applies only to Saccharomyces cerevisiae antigens, because no analogous immune responses could be detected against antigens derived from the yeast Arxula adeninivorans.