Mounting evidence has demonstrated that the immunomodulatory effects of TSC on immune cells are dependent on various soluble paracrine factors, including interleukin-1 receptor antagonist (IL-1ra), IL-10, transforming growth factor-β (TGF-β), indoleamine 2,3-dioxygenase (IDO), prostaglandin E2(PGE2) and C-C Motif chemokine Ligand 2 (CCL2) (15, 17, 23, 24). The gene discussed is CCL2; the disease is tuberous sclerosis.