CD38 and neuromyelitis optica: Interestingly, Breg subsets were found and increased in patients with various autoimmune diseases, including ankylosing spondylitis (53), primary Sjögren’s syndrome (54), diabetes mellitus (55), multiple sclerosis and neuromyelitis optica spectrum disorders (56), etc., suggesting a close involvement of CD24++CD38++ B cells in the autoimmune pathogenesis.