However, juvenile-onset SLE patient plasma and matched urine samples were positive by ELISA for the soluble form of the NKG2D ligands MICA and MICB, suggesting that kidney and/or peripheral blood may constitute the NKG2DL positive microenvironments driving NKG2D+CD4 T cell population expansions in this disease. This evidence concerns the gene CD4 and systemic lupus erythematosus.