PILAR is expressed on T cells in inflammatory synovial fluid. Proportions of PILAR+CD3+CD8− (CD4+) T cells in synovial fluid specimens from rheumatoid arthritis and gout patients using rabbit polyclonal or mouse monoclonal PILAR-specific Abs. Staining with an irrelevant mouse IgG (BD PharMingen, San Diego, CA) is additionally shown.