Immunogold labelling of tumour cells during NK/target cell interactions.
Using a system of immunocolloidal gold labelling, we have monitored the expression and distribution of transferrin receptors (TfRs) within the K562 cell line, during NK/target cell interactions. An indirect method of immunolabelling was used to effectively immunolabel tumour cells without disrupting the natural effector:target interactions. Successful localization of TfRs demonstrates the potential of the described technique for discerning antigenic distribution of other cell:cell interactions. Immunolabelling has also provided a useful method for demonstrating receptor down-regulation within NK target cells, as a proposed cause of reduced receptor expression by TPA-treated cells. Following 30 and 60 min incubation periods with TPA, approximately 15 and 30%, respectively, of the gold/antibody complexes were relocated from the surface membrane to an intracellular location within endocytotic vesicles. The demonstration of receptor down-regulation is important as a proposed cause of TPA-induced tumour cell resistance to NK-mediated cytolysis.
Zanyk
M J
MJ
Department of Pathology, University of Western Ontario, London, Canada.
Banerjee
D
D
Hearn
S A
SA
D003602:Cytotoxicity, Immunologic / Q000502:physiology*; D015536:Down-Regulation / Q000502:physiology; D006801:Humans; D007150:Immunohistochemistry; D007694:Killer Cells, Natural / Q000166:cytology*; D008854:Microscopy, Electron; D011990:Receptors, Transferrin / Q000187:drug effects; D013755:Tetradecanoylphorbol Acetate; D014407:Tumor Cells, Cultured
D011990:Receptors, Transferrin; D013755:Tetradecanoylphorbol Acetate