We therefore bred MPS mice (MPS VII, Sly disease) to TLR4 knock-out mice, and found that the double knock-out MPS animals had markedly reduced TNF-alpha, IL1-beta, RANKL and other cytokines, improved bone growth and more organized bone growth plates, and reduced chondrocyte cell death [18]. The gene discussed is TLR4; the disease is mucopolysaccharidosis.