Fig. 3

Synovial pathology and immune cell phenotypes in porcine knee joint capsule. Representative images of (a) Anterior joint capsule with synovium overlying the infra-patellar fat pad from porcine knees with normal synovial tissue (low synovitis) on left and inflamed synovial tissue (high synovitis) on right. (b) Representative images of histology sections stained with hematoxylin and eosin showing cellular infiltrate in porcine synovium with low and high synovitis. Scale bar = 1 mm. (c) Combined synovitis score summed from gross scoring of the synovium and histologic scoring of synovitis. Data presented as mean + SEM (n = 4 per group) with statistical analysis performed using unpaired t-test (*p = 0.04). (d) Representative image of immune cell phenotype of normal (low synovitis) and inflamed (high synovitis) porcine synovial cell superlots. High synovitis CD14⁺ monocytes expressed higher frequencies of SLA-DR⁺ CD163^– and SLA-DR^– CD163⁺ subsets compared to low synovitis superlots. Data reported as percent of parent gate.