Spatial Distribution of Extracellular Vesicles, Autofluorescence and CD9 Positivity Around Chondrocytes in the Superficial Layer of Articular Cartilage.

ABSTRACT: This study investigates the distribution of extracellular vesicles (EVs) in superficial articular cartilage, hypothesizing that EVs (a) are unevenly distributed in this zonally organized tissue and (b) share a pattern similar to tissue autofluorescence. Fresh unfixed superficial cartilage from the femoropatellar groove of bovine knees was analysed using multiphoton microscopy (second harmonic generation, SHG, and multiphoton-autofluorescence, MPAF). Transmission electron microscopy (TEM) and immunostaining (CD9, membrane marker; collagen type VI, pericellular matrix marker) were performed on fixed tissue. Cartilage-bone cylinders were analysed in a simulated endomicroscopic setting. Additionally, EVs were isolated from synovial fluid and chondrocyte cell culture medium to demonstrate autof

SUBMITTER: Gellhaus F 

PROVIDER: S-EPMC12538814 | biostudies-literature | 2025 Oct

REPOSITORIES: biostudies-literature