C4BPA and systemic lupus erythematosus: DEGs of neutrophils in SLE patients in these groups are shown in Fig. 2A. Among the DEGs, C4BPA expression was increased in patients with low MPO-DNA complex and low CRP with high anti-dsDNA antibody titers, whereas PAPSS1 and PLIN2 were increased in patients with high MPO-DNA complex and high CRP with low anti-dsDNA antibody titers.