Receptor-binding antiproliferative peptides

A method for identifying antiproliferative peptides, comprising the steps of:

• obtaining a predetermined cell population from a patient, wherein said predetermined cell population comprises cells expressing on their extracellular surface an immunoglobulin superfamily species having a single idiotype characteristic to the predetermined cell population;
• contacting under aqueous binding conditions said immunoglobulin superfamily species to a peptide library comprising a multiplicity of peptide library members having distinct peptide sequences;
• identifying a peptide library member that binds specifically to said immunoglobulin superfamily species idiotype as an anti-idiotype peptide;
• contacting under growth conditions said anti-idiotype peptide to said predetermined cell population or their clonal progeny and measuring an indicator of cell proliferation or activation in the predetermined cell population;
• and
• identifying an anti-idiotype peptide which inhibits cell proliferation of the predetermined cell population as an antiproliferative peptide.