A heterogeneous double antibody enzyme-linked immunoassay to measure beta-galactosidase fusion protein.

A rapid and sensitive enzyme-linked immunoassay (ELISA) to quantitate recombinant fusion proteins encoded by cloned cDNA in the bacteriophage lambda gt11 is described. Since the fusion protein is expressed in an equimolar ratio to beta-galactosidase, the assay derives the concentration of the recombinant protein in total bacterial lysates or pure preparations from the measurement of beta-galactosidase with an enzyme-linked immunoassay. This assay is a useful technique to measure the recombinant proteins for subsequent immunological and biochemical characterization.