There is provided a method of producing an antibody to an inoculated zalpha11 polypeptide comprising isolating an antibody elicited by the inoculated polypeptide, wherein the polypeptide is selected from the group consisting of: a) a polypeptide consisting of the amino acid sequence of SEQ ID NO: 72; b) a polypeptide consisting of the amino acid sequence of SEQ ID NO: 73.