CCX-CKR is expressed by cTECs and increased size, cell number, and aberrant thymic architecture in CCX-CKR^−/− mice. (A) Thymocytes and thymic stromal cells from WT mice were sorted by flow cytometry and subjected to quantitative PCR analysis to identify CCX-CKR transcript. Data are 3 biologic replicates from a single experiment. (B) Thymus weight and total viable cell counts. Pooled thymi weights from 5 independent experiments: WT, n = 39; and CCX-CKR^−/−, n = 38. Pooled cell counts from 4 independent experiments: WT, n = 28; and CCX-CKR^−/−, n = 27. Two-tailed unpaired t test with Welch correction: ***P < .0001. (C) Thymus sections from WT (left), CCX-CKR^−/− (middle), and CCR7^−/− (right) mice stained with hematoxylin and eosin. Representative images from 12 WT, 11 CCX-CKR^−/−, and 10 CCR7^−/− mice. Scale bar represents 0.5 mm. (D) Quantitation of the medulla size range ± SD: WT, n = 8; CCX-CKR^−/−, n = 11; and CCR7^−/−, n = 10. (E) Quantitation of the total, medullary, and cortical area of WT, CCX-CKR^−/−, and CCR7^−/− thymic lobes. Sections were cut in the approximate middle of the thymus, and 2D area was determined: WT, n = 8; CCX-CKR^−/−, n = 11; and CCR7^−/−, n = 10. (B,E) Bars represent mean values. (D-E) One-way ANOVA with Bonferroni posttest: **P < .01, ***P < .001.