CCL2 and early-onset autosomal dominant Alzheimer disease: Alzheimer: Higher levels of C-C motif chemokine 20 and interferon gamma were associated with an increased risk of Alzheimer's disease (AD), while higher levels of monocyte chemoattractant protein-1 and C-X-C motif chemokine 9 were linked to a reduced risk of AD (Supplementary Table S3).