Patent ID: 7405048

Claim:
A method for quantitatively or qualitatively detecting a polypeptide in a sample, comprising: (a) contacting said sample with a monoclonal antibody specific for said polypeptide to adsorb said polypeptide on said monoclonal antibody; and (b) measuring the level of immunoreaction between said polypeptide and said monoclonal antibody to determine the presence or amount of said polypeptide in said sample by using radioimmunoassay, enzyme immunoassay, or fluorescent immunoassay, wherein said polypeptide is capable of inducing interferon-γ production in immunocompetent cells and has the amino acid sequence of SEQ ID NO:1, where the symbol Xaa represents isoleucine or threonine, or has an amino acid sequence which is obtained by replacing one or two amino acids in SEQ ID NO:1 with other amino acids, by adding one or two amino acids to the N- and/or C-termini in the amino acid sequence of SEQ ID NO:1, and/or by deleting one or two amino acids from the N- and/or C-termini of the amino acid sequence of SEQ ID NO:1, while substantially not losing the activity of inducing IFN-γ production by immunocompetent cells.