CD4 and systemic lupus erythematosus: While in SLE-DKO mice, a significantly lower frequency of CD3+CD4+cells (5.5% ± 2.1%) and a higher frequency of CD3+CD8+ cells (79.4 ± 3.6%) was reported; this contrasted with a more typical distribution of CD3+CD4+ (66.2 ± 2.5%) and CD3+CD8+ (16.5 ± 2.1%) cells in the ND-DKO mice (21).