Five of these analytes also changed significantly in response to ERT in the overall ANOVA analysis: alpha-1-antitrypsin, eotaxin, lipoprotein(a), MMP-2, and serum amyloid P. Of these, only 3 were significantly lower in MPS IVA individuals and also increased during ERT: alpha-1-antitrypsin, lipoprotein(a), and serum amyloid P. MMP-2 was significantly higher in MPS IVA individuals but increased with ERT, and exotoxin was significantly lower in MPS IVA individuals but decreased with ERT. Here, MMP2 is linked to mucopolysaccharidosis type 4A.