APOE and neurodegenerative disease: To highlight the breadth and utility of the GNPC V1 resource, we present three illustrative vignettes that showcase how this harmonized dataset can be applied to address key questions in neurodegenerative disease and aging research: (1) disease-specific differential abundance profiling, (2) biological aging across organ systems and (3) protein markers of genetic risk as exemplified by the apolipoprotein E (APOE) genotype.