Lysosomal hydrolases in different compartments of rheumatoid and osteoarthrotic joints.

Tissue samples from 226 rheumatoid and osteoarthrotic joints displayed increased activities of three lysosomal enzymes compared with controls. Variations in activity were evident--one tissue cannot be blamed for all joint destruction, no one enzyme can be used as a diagnostic tool. Free enzyme activities in synovial fluid reflected those in tissues, especially in cartilage and bone. Increased values in osteoarthrotic sera, close correlation of ESR to activities in joint compartments, and higher values in synovial fluid, cartilage and bone of seronegative rheumatoid patients were recorded.