CCL21 and Alzheimer disease: Thus, the aim of the paper was to assess the serum level of CXCL-9, CXCL-10, CXCL-11, CXCL-12, CCL-17, CCL-20, CCL-21, CCL-22, CCL-27, IL-18 in two AD patient groups, below and over 10 years old.