RETNLB and systemic lupus erythematosus: However, the expression of Arg-1 was undetectable in SLE patients (p = 0.036), and a trend of lower mRNA levels of Fizz-1 (0.083 ± 0.17 fold change, p = 0.13) and IL-10 (0.48 ± 0.53 fold change, p = 0.13) were observed in SLE patients (Fig. 2c).