In addition, decreased levels of human CD56+ T cells, which are not activated by α-GalCer but have been proposed as a functional counterpart for mouse NKT cells8,43,44, might be associated with high levels of serum IgG and anti-dsDNA Abs in patients with SLE14, suggesting that CD56+ T cells may ameliorate SLE. Here, NCAM1 is linked to systemic lupus erythematosus.