SSB Antibody

Sjoegren syndrome type B antigen (SS-B or Lupus La protein) plays a role in the transcription of RNA polymerase III. SSB is probably a trancription termination factor by binding to the 3' termini of nascent polymerase III transcripts. Sera from patients with systemic lupus erythematosus (SLE) contain often antibodies that react with the normal cellular La protein as if this antigen was foreign.