Quantitation of influenza virus antigens on infected target cells and their recognition by cross-reactive cytotoxic T cells.
Monoclonal antibody to type-A influenza virus matrix (M)-protein was used to quantitate the appearance of M-protein on abortively infected P815 cells. After 16 h of infection with different type-A viruses, only a low amount of M-protein appears on the surface of infected cells (approximately 10(3) site/cell) in contrast to approximately 10(5) hemagglutinin molecules on each cell surface. However, virus replication is required for M-protein appearance. Analysis of solubilized membranes purified from 16-h-infected cells shows approximately 10(4) M-protein molecule/cell in the plasma membrane, a content that is consistent with the observed low surface expression, and that indicates that most of the M-protein is localized internally. We found no evidence that cross-reactive cytotoxic T cells could recognize M-protein; neither monoclonal antibody or hyperimmune anti-M-protein antiserum could inhibit T cell killing, either alone or in combination with monoclonal anti-H-2 antibody. Taken together, the low level of M-protein appearance and lack of T cell blocking by anti-M-protein antibody leaves doubt that M-protein is the antigen recognized by cross-reactive cytotoxic T cells.
D000818:Animals; D000914:Antibodies, Viral; D000918:Antibody Specificity; D000956:Antigens, Viral; D002478:Cells, Cultured; D003165:Complement System Proteins / Q000378:metabolism; D003602:Cytotoxicity, Immunologic; D008565:Membrane Proteins / Q000276:immunology; D051379:Mice; D009975:Orthomyxoviridae / Q000276:immunology; D009976:Orthomyxoviridae Infections / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*; D014764:Viral Proteins / Q000276:immunology; D014779:Virus Replication
D000914:Antibodies, Viral; D000956:Antigens, Viral; D008565:Membrane Proteins; D014764:Viral Proteins; D003165:Complement System Proteins