CXCR6 and juvenile polyposis syndrome: Regarding the result of IHC staining of 130 knee synovial tissues, it was confirmed that CXCR6 and CXCL16 expression was significantly higher in the PJI group compared to both the AF group (CXCR6, p = 0.0007; CXCL16, p = 0.0049) and OA group (CXCR6, p = 0.0002; CXCL16, p = 0.0030) (Figure 5m,n).