Spatial profiling of synovial tissue from patients with late-stage knee osteoarthritis.

Marked changes in synovial tissue are seen in knee osteoarthritis and are related to pain; however, the regulation of these processes are not fully understood. Spatial profiling was used to characterize cellular profiles and biological processes within important microenvironments in the synovium (intimal lining, sub-lining, and vessels) between patients that experience more pain compared to those that experience less pain. Overall design: Synovial tissue from n=32 patients with late-stage knee osteoarthritis were analyzed using spatial profiling and compared between those that experience more pain (n=16) and those that experience less pain (n=16). A tissue microarray was created with all patient samples so they could be analyzed on the same slide. Transcriptomes of intimal lining (CD68+), sub-lining area (CD45+), and vessels (aSMA+) were analyzed separately from each region of interest using GeoMx Digital Spatial Profiler and GeoMx Human Whole Transcriptome Atlas (NanoString).