title: Attachment of influenza C virus to human erythrocytes.
abstract: Binding experiments with radioactively labelled influenza C virions were carried out to investigate the interaction of the virus with human erythrocytes. The erythrocytes from any of 35 different individuals were found to contain influenza C virus-binding sites though their number was variable among the individuals and was much less than that on mouse, rat and chicken erythrocytes. Attachment of influenza C virus to human erythrocytes was inhibited completely by prior treatment of the virus with anti-HE monoclonal antibody having a strong haemagglutination inhibition activity. Pretreatment of erythrocytes with neuraminidase or the neuraminate-O-acetylesterase of influenza C virus resulted in a marked reduction in the level of virus binding. Thus it appears that human erythrocytes have a low level of O-acetylated sialic acid-containing glycoconjugates that can interact specifically with the HE glycoprotein of influenza C virus. Proteolytic digestion of erythrocytes with ficin, bromelain or V-8 protease inhibited virus binding almost completely, suggesting that the erythrocyte receptor for influenza C virus is a glycoprotein. In contrast to these enzymes, trypsin treatment of erythrocytes reduced virus binding by only about 50%, and alpha-chymotrypsin treatment did not inhibit at all. It was also found that treatment of erythrocytes with monoclonal antibody to the M or N blood group antigen greatly inhibited virus binding to the cells. These results, taken together, suggest that most influenza C virus receptors on human erythrocytes, if not all, reside on glycophorin A which is known to possess the M or N blood group activity.
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D002645:Chickens; D004912:Erythrocytes / Q000378:metabolism / Q000382:microbiology*; D006021:Glycophorins / Q000378:metabolism; D006386:Hemagglutination Tests; D006801:Humans; D009982:Gammainfluenzavirus / Q000472:pathogenicity*; D008951:MNSs Blood-Group System; D009439:Neuraminidase / Q000494:pharmacology; D009975:Orthomyxoviridae / Q000472:pathogenicity*; D010447:Peptide Hydrolases / Q000494:pharmacology; D051381:Rats; D011991:Receptors, Virus / Q000378:metabolism*; D014764:Viral Proteins / Q000276:immunology; D014776:Virus Cultivation
chemical_list: D000911:Antibodies, Monoclonal; D006021:Glycophorins; D008951:MNSs Blood-Group System; D011991:Receptors, Virus; D014764:Viral Proteins; D009439:Neuraminidase; D010447:Peptide Hydrolases