CXCL1 and Alzheimer disease: Since we have shown that fibroblasts were the major source for the release of AD-related IL-6, CCL2, CXCL1, CXCL8 and CXCL10 in the co-culture system (Figure 3A–E), it is reasonable that both IL-31 and IL-33 exhibited significant higher activation of ERK, Akt, JNK and NF-κB in fibroblasts than that of eosinophils (Figure 6C–F).