Lymphocyte B hyperactivity and cell-mediated immune deficiency are characteristic features of systemic lupus erythematosus. This imbalance is seen in cytokine production. T lymphocyte production of interleukin-2 is defective while proinflammatory cytokines such as IL1 beta, IL6 and TNF alpha increase spontaneously during flare-ups. However, the capacity of the monocytes in these patients to produce cytokines is reduced after stimulation by exterior agents such as LPS. Moreover, production of interleukin 10 is increased in lupus patients. Most likely, it is this increase in interleukin 10 production which causes the disrupted immunity in this disease.