CD19 and Autoimmunity: LM-B cells are termed double-negative B cells (CD19+CD27−IgD−) and described as “atypical.” They have been implicated in age-related chronic inflammation and in autoimmunity.21 Loss of the ability to reign in autoimmunity, a characteristic of senescent B (and T) cells, may cause the rise of potentially pathogenic autoantibodies including those to neural antigens.