[Pathogenesis of inflammatory cartilage destruction in adjuvant arthritis in the rat]

By morphological studies on adjuvant arthritis of the rat the following questions were investigated: (1) the participation of polymorphonuclear granulocytes in inflammatory cartilage destruction, and (2) the ability of pannus tissue to invade living cartilage. Polymorphonuclears, identified by a histochemical technique, were observed in the pannus tissue beneath partial destructed cartilage. By means of 35S-autoradiography it was observed that in the neighbourhood of the invading pannus tissue chondrocytes usually retained the capacity to incorporate the radioactive material. From the observations it is concluded that (1) polymorphonuclears are important cells in inflammatory cartilage destruction, even in non-septic arthritis and that (2) pannus tissue may invade a cartilage with viable chondrocytes.