Immunoelectron Microscopy of Parainfluenza Virion Glycoproteins with Polyclonal and Monoclonal Antibodies: Movement of Glycoprotein with Monoclonal Antibody

Two glycoproteins (HN and F) of parainfluenza virus were immunogold-labeled with polyclonal and monoclonal antibodies, respectively, and their labeling patterns were compared. Both glycoproteins HN and F were efficiently and homogeneously labeled with polyclonal antibodies, whereas they were labeled much less and heterogeneously with monoclonal antibodies. When either protein was initially labeled with monoclonal antibody, and then the other one, with polyclonal antibody, immunolabels of two glycoproteins were almost completely segregated. Although this segregation deformed virion morphology, it supported the concept of monoclonal antibody-mediated movements of glycoproteins. Key words: parainfluenza virus, glycoprotein, immunogolds, monoclonal antibody In a previous study,2) we found by using immunoelectron microscopy that influenza virus neuraminidase (NA) glycoproteins (GP) on virion surfaces appeared homo-geneously with anti-NA polyclonal antibody (pAb), whereas they appeared in clusters when anti-NA mono-clonal was used (mAb), the former reflecting a tru