title: A protein preparation from Mycobacterium kansasii culture filtrate has biological activity similar to that of hCG and cholera toxin in human cell lines.
abstract: A protein preparation, from culture filtrates from a strain of Mycobacterium kansasii (MK precipitate), which cross reacts with antibodies to human chorionic gonadotropin (hCG) beta subunit and antibodies to cholera toxin beta subunit, has been isolated. A tissue culture assay was used to detect the ability of this preparation to affect the antiviral activity of interferons and to visualize changes in cell shape and cell-cell contact caused by this preparation. A cholera toxin containing precipitate (CT precipitate) from cultures of Vibrio cholerae and commercially prepared hCG were used for comparison. It was found that MK, CT, and hCG may cause reduction or apparent enhancement of interferon antiviral activity or may have no effect. The effect that is observed depends on which test protein the cells are treated with, the type of interferon used, and which cell line is employed in the assay. All three protein preparations had visible effects on the shapes of the cells and the way the cells interacted to form a monolayer.
mesh_terms: D001426:Bacterial Proteins / Q000276:immunology / Q000494:pharmacology*; D002460:Cell Line; D002470:Cell Survival; D002772:Cholera Toxin / Q000276:immunology / Q000494:pharmacology*; D006063:Chorionic Gonadotropin / Q000276:immunology / Q000494:pharmacology*; D003429:Cross Reactions; D007372:Interferons / Q000037:antagonists & inhibitors / Q000276:immunology / Q000494:pharmacology; D009161:Mycobacterium / Q000032:analysis*; D009170:Nontuberculous Mycobacteria / Q000032:analysis*; D014721:Vesicular stomatitis Indiana virus / Q000276:immunology
chemical_list: D001426:Bacterial Proteins; D006063:Chorionic Gonadotropin; D007372:Interferons; D002772:Cholera Toxin