Thus, β2m-deficiency may affect lupus via at least three possible mechanisms: 1) the effects of FcRn on IgG catabolism; 2) the immunoregulatory role of CD1d, and 3) the ability of CD1d to bind phospholipids to induce anti-phospholipid autoimmunity. Here, B2M is linked to systemic lupus erythematosus.