A new inclusion body in rheumatoid synovia.

As part of the current research programme these laboratories are investigating the synovia of normal and abnormal human joints by light and electron microscopy. By synovia is meant the material lining joints and tendon sheaths on the interior of the fibrous capsule, including, therefore, synovial cells, loose connective tissue, blood vessels, and inflammatory cells which may be present. Several descriptions of the fine structure of normal or near normal human synovium have been published (Barland, Novikoff, and Hamerman, 1962, and Coulter, 1962), and also of the synovium in rheumatoid arthritis (Barland, Novikoff, and Hamerman, 1964). However, none of these has included a study of blood vessels. In view of the importance of the alterations in blood vessels seen on light microscopy (Kulka, Bocking, Ropes and Bauer, 1955), it was thought worth while to pay these particular attention during this ultrastructural study, and it is the purpose of this paper to draw attention to some endothelial inclusion bodies occurring within, or immediately adjacent to, small synovial blood vessels in rheumatoid arthritis which we think sufficiently interesting to merit further investigation. A brief preliminary report has already been published (Highton, Caughey, and Rayns, 1965)