Elevated expression levels of IL-4 and its receptor (IL4R) were notably observed in both AD and CNPG cohorts—IL-4 (AD median 2.88 × 10−5 IQR [1.49 × 10−5; 5.50 × 10−5] > HC, p < 0.05; CNPG 3.58 × 10−5 [2.90 × 10−5; 5.51 × 10−5] > HC, p < 0.001) and IL4R (AD 4.17 × 10−3 [2.50 × 10−3; 5.04 × 10−3] > HC, p < 0.001; CNPG 2.12 × 10−3 [7.64 × 10−4; 3.12 × 10−3] > HC, p < 0.005; Figure 1a,b)—compared to the healthy controls (HC IL-4: 9.33 × 10−6 [5.75 × 10−6; 1.60 × 10−5], IL-4R: 3.03 × 10−4 [1.75 × 10−4; 7.11 × 10−4]). Here, IL4 is linked to Alzheimer disease.