Interestingly, the presence of NMO antibodies in SS patients has been described [75, 93, 95, 97], possibly as expression of polyclonal B cell activation typical of SS [95]; on the other hand, patients with NMO frequently have other autoantibodies of a variety of specificities, and among the commonest of these autoantibodies are SSA and SSB [74]. This evidence concerns the gene SSB and neuromyelitis optica.