Moreover, indoxyl sulphate (IS), a uremic toxin found in larger amounts in patients with CKD, binds to the aryl hydrocarbon receptor of monocytes inducing TNF-α secretion, which in turn induces CX3CL1 expression in endothelial cells with the CXCR1 ligand and CD4+/CD28− T cells (most abundant in patients with renal disease). The gene discussed is TNF; the disease is chronic kidney disease.