HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Celada, F. Articles by Radojkovic, J. Search for Related Content PubMed Articles by Celada, F. Articles by Radojkovic, J.

An in Vitro Immuno-Enzymatic Assay of Tumor Antigens in the Mouse with -Galactosidase¹

Laboratorio di Biologia Cellulare, C.N.R., and the Istituto Regina Elena per lo Studio e la Cura dei Tumori, Roma, Italy

Abstract

A method for detection of the primary binding of soluble tumor-associated antigens by antibodies has been developed by using an enzyme immunoassay (EIA). A heteroantiserum was produced by injecting tumor cells from a chemically induced murine sarcoma into rabbits, and antibodies reacting with most normal tissue components were removed by exhaustive in vivo absorption. A soluble preparation of tumor cells, obtained by 3 M KCl extraction, was conjugated to -galactosidase from Escherichia coli. The antibody binding was measured by determining the enzyme activity that could be separated by anti-antibody coprecipitation. The reaction follows saturation kinetics, and nonlabeled antigen can be readily quantitated by inhibition. The present method detects determinants common to several MC-induced tumors on the same mouse strain but absent in normal cells and nonrelated tumors in addition to individual tumor-specific transplantation antigens. The sensitivity and simplicity of the new method compare favorably with a binding assay that utilizes radioactive iodine as a label. Thus, EIA becomes a flexible tool for the further characterization and purification of these antigens.

Footnotes

¹ A preliminary report on this work was presented at the 59th Meeting of the Federation of American Societies for Experimental Biology (Atlantic City, 13–18 April 1975). Work in the Regina Elena Cancer Institute was partially supported by a grant of the Italian Research Council to Professor Ercole Sega.

² Supported during part of this work by a Fellowship from the Italo-American Medical Education Foundation.

³ Present address: Departamento de Bioquimica y Quimica, Universidad de Chile, Santiago, Chile.