Osmium tetroxide in antigen-induced arthritis: failure to inhibit joint destruction.

Antigen induced arthritis (AIA) was elicited in 28 adult rabbits using ovalbumin. All animals developed an intensive monarthritis manifested by local heat and swelling. Two, 7 and 21 days later, respectively, 0.3 ml of 1 per cent OsO4 was injected into the arthritic knees of three groups of 9 rabbits. The rabbits were killed 1, 3 and 6 months later. No modifying influence on the severe to complete cartilage destruction was evident. One group of 8 rabbits received only OsO4 and the cartilage of these animals remained intact after 6 months.