IL2 and systemic lupus erythematosus: The mean levels of IL-2 production by peripheral blood T cells were as follows: active SLE, 5.4 ± 5.5 pg/ml (n = 11); inactive SLE, 6.3 ± 4.6 pg/ml (n = 10); and normal control individuals, 10.6 ± 10.8 pg/ml (n = 12).