A technique for investigating the antigenicity of cultured rheumatoid synovial cells.

Antisera to rheumatoid and nonrheumatoid synovial cells were prepared by: intraarticular injection of rabbits with these cells, subsequent synovectomy, and autologous immunization of each animal with the cultured rabbit synovial cells, or homogenized whole rabbit synovial membrane. Resultant antisera were studied by immunofluorescence and 51chromium cytotoxicity tests against other cultured rheumatoid and nonrheumatoid cells. Activity of positive sera could be removed by absorption with nonrheumatoid cells, except for one antiserum which appeared to produce immunofluorescent staining specific for rheumatoid cells.