Patent ID: 7235376

Claim:
A method for determining the amount of free gastrin-17 (G17) or gastrin-34 (G34) in a biological fluid sample, comprising the steps of: (a) obtaining a biological fluid sample comprising a gastrin hormone from a patient; (b) providing an immobilized antibody selected from the group consisting of an immobilized antibody that selectively binds an N-terminal epitope of G17 and an immobilized antibody that selectively binds an N-terminal epitope of G34; (c) incubating the sample to allow binding of G17 or G34 in the sample to said antibody to produce an immobilized complex of said antibody bound to the G17 or G34; (d) washing the immobilized complex to remove unbound components, and reacting the complex with a detectable marker-conjugated monoclonal antibody that selectively binds a C-terminal epitope of G17 or G34, to form a detectable marker-conjugated antibody complex; (e) washing the immobilized detectable marker-conjugated antibody complex, and incubating with a development reagent; and (f) measuring the developed reagent to determine the amount of free G17 or free G34 in the biological fluid sample; wherein the monoclonal antibody that selectively binds a C-terminal epitope of G17 or G34 is the monoclonal antibody produced by the hybridoma 458-1 (ATCC accession no. PTA-5896).