Patent ID: 8859209

Claim:
A method for obtaining, from a plurality of different randomly generated IgY antibodies specific for one or more primary antigens, one or more isolated randomly generated IgY antibodies, but not all of said plurality of IgY antibodies, wherein said isolated IgY antibodies are also specific for one or more secondary antigens, said method comprising the steps of: i) generating a peptide library by random peptide synthesis, wherein the resulting peptides are randomized at each amino acid residue and at least the 20 naturally occurring amino acids are represented at each amino acid position of peptides in the library, wherein the length of the different peptides is in the range from 5 amino acid residues to 15 amino acid residues, wherein each peptide of the peptide library is a primary antigen, ii) generating a plurality of IgY antibodies by immunizing each of a plurality of avian organisms of the same or different species with a composition comprising peptides produced in step i), thereby generating a plurality of different randomly generated IgY antibodies, iii) providing one or more secondary antigens to be tested, wherein said one or more secondary antigens is immobilized to a support, iv) contacting said one or more secondary antigen(s) with the plurality of different IgY antibodies specific for one or more primary antigens as generated in step ii), v) washing to remove unspecifically bound antibodies, and recovering specifically bound antibodies, thereby obtaining one or more IgY antibodies having a specificity for both one or more of said primary antigens and one or more of said secondary antigens, wherein the primary and secondary antigens are not identical, and wherein the obtained IgY antibodies specific for said one or more secondary antigens have been raised against said one or more primary antigens only.