C-reactive protein expression is up-regulated in apical lesions of endodontic origin in association with interleukin-6.

Introduction: C-reactive protein (CRP) is the prototype component of acute-phase proteins induced ultimately by interleukin (IL)-6 in the liver, but it is unknown whether periradicular tissues locally express CRP. The present study aimed to identify whether CRP messenger RNA synthesis occurs in situ within apical lesions of endodontic origin (ALEOs) and healthy periodontal ligament and its association with IL-6 and to determine their protein levels and tissue localization.

Methods: Patients with asymptomatic apical periodontitis and healthy volunteers presenting at the School of Dentistry, University of Chile, Santiago, Chile, were enrolled.