In accordance with the present invention, there are provided novel TRAF-Protein-Binding-Domain polypeptides (TPBDs). The invention also provides nucleic acid molecules encoding TPBDs, vectors containing these nucleic acid molecules and host cells containing the vectors. The invention also provides antibodies that can specifically bind to invention TPBDs. Such TPBDs and/or anti-TPBD antibodies are useful for discovery of drugs that suppress autoimmunity, inflammation, allergy, allograph rejection, sepsis, and other diseases.