CD80 and systemic lupus erythematosus: The percentages of CD134 and CD80 expressing IL-17 producing T-cells were significantly increased in SLE patients in comparison to healthy controls (CD134: 71.78 ± 14.51% vs. 51.45 ± 16.58%, P = 0.002; CD80: 25.5 ± 14.99% vs. 14.99 ± 5.74%, P = 0.02) (Figure 3a, b).