Production of anti-self bodies from antibody segment repertories and displayed on phage

A method of producing a member of a specific binding pair (sbp member), which sbp member is a human antibody or human antibody fragment having an antigen binding site with binding specificity for a target human self antigen, the method comprising:

• (a) providing a library comprising filamentous bacteriophage that each display at their surface an sbp member, wherein each filamentous bacteriophage that displays at its surface an sbp member contains nucleic acid with sequence encoding the sbp member displayed at the surface of that filamentous bacteriophage or encoding a polypeptide chain of the sbp member displayed at the surface of that filamentous bacteriophage, wherein nucleic acid sequences encoding sbp members or polypeptide chains displayed in the library are based on human antibody sequences obtained without immunizing a human with the target human self antigen and without obtaining nucleic acid from a human having an autoimmune disease against the target human self antigen and without determining that human antibodies with binding specificity for said target human self antigent are detectable in a human;
• and
• (b) selecting one or more specific binding pair members with binding specificity for said target human self antigen, by binding with said target human self antigen one or more sbp members displayed at the surface of filamentous bacteriophage.