title: Quantitative ultramicro-scale immunoenzymic method for measuring Ig antigenic determinants in single cells.
abstract: The Fluoro Ultra Micro Enzyme Linked Immuno Assay (FUMELIA) allows one routinely and quantitatively to measure a few thousand antigenic determinants on single cells. Highly purified Escherichia coli beta-galactosidase has been coupled to specific antibodies. By use of the Parafilm microcuvette techniuqe, the activity of the antibody-conjugated beta-galactosidase is assayed with a conventional spectrophotofluorometer. Attempts were undertaken to sensitize FUMELIA even further, so as to be able to detect a very few antigenic sites. It seems that even in its present state of development FUMELIA is more sensitive for the quantitation of cell-associated antigens than are techniques in which radiolabeled reagents are used. The potential of FUMELIA is illustrated by the quantitative measurement of membrane-bound immunoglobulins on single lymphocytes. It could be shown that T-cells as well as C-cells can synthesize Ig antigenic determinants. Thus it seems likely that T-cell receptors will, after all, be found to be immunoglobulins.
mesh_terms: D000818:Animals; D000939:Epitopes / Q000032:analysis*; D004926:Escherichia coli / Q000201:enzymology; D005347:Fibroblasts / Q000276:immunology; D005455:Fluorescent Antibody Technique; D006801:Humans; D007124:Immunoenzyme Techniques; D007136:Immunoglobulins / Q000032:analysis*; D007700:Kinetics; D008214:Lymphocytes / Q000276:immunology; D051379:Mice; D008832:Microchemistry; D001616:beta-Galactosidase / Q000378:metabolism
chemical_list: D000939:Epitopes; D007136:Immunoglobulins; D001616:beta-Galactosidase