Cellular localizations and processing of the two molecular forms of the Hodgkin-associated Ki-1 (CD30) antigen. The protein kinase Ki-1/57 occurs in the nucleus.
The Ki-1 antibody not only detects a Hodgkin-associated membrane molecule of 120 kd (Ki-1/120 = CD30), but also reacts with an independently synthesized molecule of 57 kd (Ki-1/57) that only occurs intracellularly. Hodgkin's disease-derived cell lines L428 and L540 contain both Ki-1-reactive antigens, whereas others, e.g., U266/Bl myeloma cells, only express the intracellular Ki-1/57. The present immunoelectronmicroscopic analysis detected the Ki-1/57 antigen of U266/Bl cells not only in the cytoplasm, but also in association with the nuclear envelope, chromatin structures, and nucleoli. This Ki-1/57-specific type of labeling also was observed in L428 and L540 cells that, in contrast to U266/Bl cells, showed an additional staining of cell membranes and cytoplasmic vesicles. These results were confirmed by two independent methods: 1) cytocentrifuge preparations of isolated nuclei of L540 cells showed a spotted Ki-1-specific labeling, 2) immunoprecipitations demonstrated that the Ki-1/57, but not the Ki-1/120 antigen, was transferred into the nuclei of L540 and U266/Bl cells, whereas the Ki-1/120 antigen with its 90-kd precursor remained in the non-nuclei fraction of L540 cells.
Rohde
D
D
Biochemisches Instituts, Medizinischen Fakultät, Christian-Albrechts-Universität zu Kiel, Federal Republic of Germany.
Hansen
H
H
Hafner
M
M
Lange
H
H
Mielke
V
V
Hansmann
M L
ML
Lemke
H
H
D015703:Antigens, CD / Q000032:analysis*; D000951:Antigens, Neoplasm / Q000032:analysis*; D002458:Cell Fractionation; D002467:Cell Nucleus / Q000276:immunology*; D006689:Hodgkin Disease / Q000276:immunology* / Q000473:pathology; D006801:Humans; D007124:Immunoenzyme Techniques; D017730:Ki-1 Antigen; D016253:Microscopy, Immunoelectron; D011233:Precipitin Tests; D011494:Protein Kinases / Q000032:analysis*; D014407:Tumor Cells, Cultured
D015703:Antigens, CD; D000951:Antigens, Neoplasm; D017730:Ki-1 Antigen; D011494:Protein Kinases