SS-A (Ro) and SS-B (La) antibodies have a strong association with Sjogen’s syndrome and can be used to support the clinical diagnosis. SS-A is present in 70 - 75% and SS-B in 60 - 65% of patients with Sjogren’s syndrome. However, both SS-A and SS-B antibodies are present in SLE and other connective tissue disorders, so their presence must be interpreted in the clinical context. The BioPlex 2200 test system uses an affinity purified SS-A 60 antigen, a second SS-A 52 recombinant antigen, and an affinity purified SS-B antigen.