TNFSF13B and Sjogren syndrome: To investigate whether the elevated levels of BLyS contributed to relapse, we examined the relationship between elevated levels of BLyS and relapse, we found that patients who relapsed had a higher level of BLyS in serum, while those who remained in remission had declining levels of BLyS after rituximab therapy (Fig 3D; see Table 1 for patient demographics); a finding also previously reported for Sjögren's syndrome [35].