PSIP1 and systemic lupus erythematosus: Anti-DFS70 antibodies could be used to exclude the diagnosis of SLE in patients (5) because the frequency of monospecific anti-DFS70 antibodies in SLE patients was reported between 0.4% to 3.1% (6–8), as well as the absence of anti-DFS70-positivity in HI developing SLE after 5 years of follow-up (9).