CD19 and neoplasm: A study showed that B7-H4 is involved in the pathological changes of rheumatoid synovium in rheumatoid arthritis progression and expressed on CD19(+) B cells and CD14(+) monocytes, but not on CD3(+) T cells.[42] According to our results, immune cell expression of B7-H4 seemed to be more consistent with the progression of the disease than tumor cell expression of B7-H4.