SSB and systemic lupus erythematosus: However, large screens of systemic lupus erythematosus and Sjögren's syndrome patient's sera for autoantibodies against La epitopes did not identify autoantibodies reactive with the La/SS-B-derived peptide domain used in the UniCAR system (MP Bachmann, unpublished, and see, for example, Yiannaki et al.46).