The number of Glial fibrillary acidic protein (GFAP)-positive astrocytes and ILB4-positive microglia cells was augmented in all studied human MPS cortex tissues except for those of the non-neurological MPS II patient 902 (Figure 3A), suggesting that neuroinflammation previously reported in all mouse models was also heavily present in human patients. Here, GFAP is linked to mucopolysaccharidosis type 2.