CCL18 and Parkinson disease: Based on these findings, a recent study by Galper et al. explored whether ferritin, cluster of differentiation (CD)162, CC Chemokine Ligand (CCL)18, and chitotriosidase (immune biomarkers typically associated with GD) were also altered in GBA carriers with or without PD, but these plasma biomarkers were not relevant for the stratification of PD risk in carriers of heterozygous GBA pathogenic variants [66].