Migration behavior of total thymocytes (A) and thymocyte subsets, CD4⁺ SP (B), DP (C), DN (D), and CD8⁺SP (E) subsets, in chemotactic environments formed by SDF-1 and CKβ-11/MIP-3β/ELC. The 2 chemokines were added to upper or lower chambers as indicated in the Fig (+ and − denote the presence and absence of indicated chemokines, respectively) at optimal concentrations (500 ng/mL for CKβ-11/MIP-3β/ELC and 300 ng/mL for SDF-1). Thymocytes depleted of non-T cells were used as input cells for chemotaxis. Cell migration to lower chambers is expressed as the mean percentage of migration (±differences of duplicated experiments) of input thymocyte subsets added in the upper chamber at the start time of chemotaxis. Significant differences (P < .05) were observed between the following 2 bars: 1 and 2, 1 and 3, 2 and 4, 3 and 5, 4 and 7, 5 and 6, 2 and 8, 3 and 8, 8 and 10, and 9 and 11 (for [A]); 1 and 2, 1 and 3, 2 and 4, 3 and 5, 4 and 7, 3 and 8, 8 and 9, and 10 and 11 (for [B]); 1 and 2, 1 and 3, 3 and 5, 5 and 6, 2 and 8, and 9 and 11 (for [C]); 1 and 3, 3 and 5, 5 and 6, 2 and 8, and 9 and 11 (for [D]); and 1 and 2, 1 and 3, 2 and 4, 3 and 5, 4 and 7, 5 and 6, 3 and 8, 8 and 9, 8 and 10, and 10 and 11 (for [E]).