CD4 and systemic lupus erythematosus: Several lines of evidence indicate that B cells are essential to the disease process andcould present intrinsic abnormalities (3, 4): (1) B cells produce the autoantibodies; (2) inmurine spontaneous models of SLE, B cells are activated before the disease onset, and inhumans, autoantibodies are detectable long before the first symptoms (5); (3) murine models of SLE mice devoid of mature Bcells no longer develop lupus phenotype (6); (4)it seems that the important role of B cells in lupus could also implicate their functionof antigen presentation to CD4 T cells, and/or cytokine secretion (7).