Fujitsuka et al. evaluated the levels of 8 pro-inflammatory factors (EGF, IL-1β, IL-6, MIP-1α, TNF-α, MMP-1, MMP-2, and MMP-9), collagen type II, and DS, HS (HS0S, HSNS), and KS (mono-sulfated, di-sulfated) in blood samples of MPS II, MPS IVA and MPSIVB patients. Here, MMP9 is linked to mucopolysaccharidosis type 4A.