Expression of CCL19, CCL21 and CCR7 in AS and OA ligament tissue (LT). (A) RT-PCR analysis revealed the mRNA expression levels of CCL19, CCL21 and CCR7 in AS (n = 31) LT compared to OA (n = 19) LT (P = 0.034, 0.004 and 0.155, respectively). The data are expressed as the ΔCt value (Ct target gene-Ctβactin ) between the OA and AS groups, and the Mann–Whitney U-test was performed. (B-D) AS (n = 15) and OA (n = 15) LT were stained with rabbit anti-human CCL19 (B), rabbit anti-human CCL21 (C) or rabbit anti-human CCR7 (D), and the immunostaining was expressed as the mean density ± standard deviation (SD). The expression levels of CCL19, CCL21 and CCR7 were compared between the AS and OA groups, with P values of 0.016, 0.023 and 0.191, respectively. *P < 0.05; **P < 0.01; n.s. = no significance. The original magnification is × 200 in B, C, and D.