Still no evidence for heterogeneity in Best's vitelliform macular dystrophy.

Abstract

<h3>Background</h3> Early, reproducible, sensitive imaging biomarkers are an unmet need in experimental osteoarthritis (OA) evaluation. Electron microscopy may reveal joint changes prior to soluble biomarkers. <h3>Objectives</h3> This study describes very early, quantitative, articular cartilage surface damage in posttraumatic experimental OA models allowing determination of disease severity. <h3>Methods</h3> Mice (5/group) were subjected to anterior cruciate ligament transection (ACLT), ACLT plus meniscectomy (MNCT), as OA models, or sham surgery and sacrificed 3, 7 or 14 days later. Articular cartilage was collected and processed for optical (H&amp;E; Safranin O staining) or scanning electron microscopy (SEM) analysis. Histology was graded using Osteoarthritis Research Society International (OARSI) parameters whereas cartilage thickness, roughness and damage index were evaluated under SEM. <h3>Results</h3> Optical microscopy did not reveal significantly relevant cartilage changes in OA models <i>vs</i> controls. Femoral and tibial cartilage thickness were significantly reduced in mice subjected to ACLT or MNCT at 7 and 14 days postsurgery (P&lt;0.05). Cartilage roughness was significantly increased in MNCT agroup as early as 3 days postsurgery, as compared to sham and ACLT groups, being sustained up to 14 days in both femoral and tibial extremities. Articular damage index using SEM was more severe at 14 days postsurgery in ACLT and MNCT <i>vs</i> control groups (P&lt;0.05). <h3>Conclusion</h3> Posttraumatic experimental OA display quantitative cartilage changes at SEM with increased roughness and thickness as early as 3 days post induction. In addition to unravel very early ultrastructural cartilage damage, these changes may be used as early surrogates for joint damage in experimental OA. <h3>Disclosure of Interests</h3> None declared