title: Papain solubilization of the Epstein-Barr virus-induced membrane antigen.
abstract: The Epstein-Barr virus (EBV)-induced membrane antigen (MA) was successfully solubilized from the membranes of viable EBV-infected Raji cells by treatment with papain (5 to 6 U per 1 X 10(7) to 2 X 10(7) cells). The loss of MA from viable cells was monitored by membrane immunofluorescence and antibody-dependent cellular cytotoxicity. Soluble MA was demonstrated in papain digests through inhibition of antibody-dependent cellular cytotoxicity and by inhibition of the binding of anti-MA antibodies to cells as detected by use of 125I-labeled staphylococcal protein A. Approximately 75% of the MA activity in the extracts was not sedimentable at 100,000 X g,, indicating that the majority of EBV MA activity that was released by this procedure was associated with small-molecular-weight material. Antiserum prepared from an owl monkey immunized with these papain extracts contained antibody to MA and neutralizing antibodies, but lacked detectable antibodies against viral capsid antigens and EBV-induced early antigens.
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000096:biosynthesis; D000951:Antigens, Neoplasm / Q000302:isolation & purification*; D000956:Antigens, Viral / Q000302:isolation & purification*; D002460:Cell Line; D002462:Cell Membrane / Q000187:drug effects / Q000276:immunology; D003601:Cytotoxicity Tests, Immunologic; D000939:Epitopes; D005455:Fluorescent Antibody Technique; D000882:Haplorhini; D004854:Herpesvirus 4, Human / Q000276:immunology*; D010206:Papain / Q000494:pharmacology*; D012995:Solubility
chemical_list: D000914:Antibodies, Viral; D000951:Antigens, Neoplasm; D000956:Antigens, Viral; D000939:Epitopes; D010206:Papain