DEFA1 and juvenile polyposis syndrome: In order to determine PJI-associated gene expression patterns in periprosthetic tissues, we compared gene expression levels of 12 candidate molecules (TLR1, -2, -4, -6, and -10, DEFA1, LTF, IL1B, BPI, CRP, IFNG, and DEFB4A) previously reported as potential biomarkers for detection of PJI in tissues obtained from patients with TJA during revision surgery.