CCX-CKR regulates circulating and peripheral LN chemokine abundance. (A) Diluted serum, or protein lysates from LNs (pooled inguinal, axillary, and brachial LNs) or spleens, from resting wild-type, CCR7^−/−, or CCX-CKR^−/− mice (8- to 16-week-old males) were analyzed using a 2-site ELISA for CCL21. Concentrations were calculated from a standard curve of serial dilutions of recombinant CCL21. Each data point shown is the concentration of CCL21 (per milligram or per milliliter) in that tissue from each individual mouse. The mean ± SD is indicated (***P < .001, **P < .01). (B) Diluted serum, or protein lysates from LNs (pooled inguinal, axillary, and brachial LNs) or spleens, from resting wild-type or CCX-CKR^−/− mice (8- to 16-week-old males) were analyzed using a 2-site ELISA for CCL19. Concentrations were calculated from a standard curve of serial dilutions of recombinant CCL19. Each data point shown is the concentration of CCL19 (per milligram or per milliliter) in that tissue from each individual mouse. The mean ± SD is indicated (***P < .001, **P < .01). As indicated, serum CCL19 levels were below the limit of detection (< 100 pg/mL). In all cases, data are pooled from at least 2 individual experiments.