Stereospecificity of opiate receptors in a synchronized culture of NG108-15 cells probed with fluorescent anti-idiotypic antibodies

M Ornatowska and JA Glasel

Department of Biochemistry, University of Connecticut Health Center, Farmington 06030.

The stereospecificity of the binding of an anti-opiate receptor, anti- idiotypic antibody to receptors on a synchronized NG108-15 neuroblastoma x glioma cell culture has been examined by fluorescence labeling of the antibodies. We had previously found that unsynchronized NG108-15 cultures showed high specificity (reversibility by receptor- binding ligands) of antibody labeling. However, only a subpopulation additionally showed stereospecific labeling (nonreversibility by non- receptor-binding opiate enantiomers). In the present work we find that the percentage of cells that display stereospecific fluorescence is highly dependent upon position in the cell cycle. Furthermore, the properties of the bound fluorescence, with respect to sensitivity to photobleaching, also depend upon position in the cell cycle. The fluorescence behavior of labeled synchronized cell populations after treatment to inhibit de novo glycosylation is also reported. The results reported here may have implications concerning the structure of the opiate receptor complex and efforts to solubilize the binding protein in its native form.

Volume 40, Issue 3, pp. 354-359, 09/01/1991
Copyright © 1991 by American Society for Pharmacology and Experimental Therapeutics