The phenotype of CCL5+ synovial T cells diverges from the effector memory phenotype. Flow cytometric analysis of peripheral blood (PB) and synovial cells. (a) Cells were stained for CD3, CD8 and CR7 and CD28. The majority of synovial fluid (SF) T cells were CCR7- (upper panels). However, within the CCR7- population of CD8+T cells, synovial T cells showed maintained high expression of CD28 compared to CD8+CCR7- T cells from PB (lower panel). (b) Costaining for CD8, CCR7, CCL5 and CD28 confirmed that the synovial CCR7-CD28+CD8+ cells also contained high levels of intracellular CCL5; positive staining for CCL5 was defined by comparison with isotype-matched control staining. (c) The pattern of CCL5+ staining seen in CD8+CD28+ T cells was seen in a total of 11 sets of samples (4 persistent oligoarticular, closed triangles; 5 extended oligoarticular, closed circles; and 2 polyarticular, closed squares), when comparing cells from PB and SF.