CD274 and systemic lupus erythematosus: Depleting PD-1-specific lymphocytes on non-obese diabetic mice attenuates symptoms of autoimmune encephalomyelitis on them without a negative effect on the adaptive immune response.49 In the current study, percentages of PD-L1+ monocytes in patients with SLE were tended to inversely correlate with the score of SLEDAI-2K (figure 4).