HISTOLOGICAL DISTRIBUTION OF THE INTERLEUKIN-4 RECEPTOR (IL4R) WITHINTHE NORMAL AND PATHOLOGICAL SYNOVIUM

The authors sought the synovial distribution of the interleukin-4 rece ptor in the synovium of 3 normal subjects, 5 cases of osteoarthritis ( OA) and 10 cases of rheumatoid arthritis (RA) and various other inflam matory arthritic conditions. The specific receptor for interleukin-4 w as mainly found on cells around subintimal blood vessels and within ly mphocytic aggregates where dendritic-like cells were strongly stained. Conversely, synovial lining cells did not express the interleukin-4 r eceptor. In conclusion, it is believed that the expression of interleu kin-4 receptor is restricted to the early activation stage of the mono nuclear cells in the pathological joint.