DFS pattern and DFS70 autoantibody testing: comments on the article “Investigation of anti-DFS70 antibody in patients with systemic autoimmune rheumatic diseases”

Excerpt

I read with great interest the article published by Peker et al. (Clinical Rheumatology (2019) 38:3627–3633.) [1]. It is interesting that their conclusion was similar to the observation we have published prior [2]. Currently, verification of the nuclear dense fine speckled (DFS) pattern, also known as the AC-2 pattern, by a specific anti-DFS70 assay is considered essential to exclude the pseudo-DFS pattern [3]. Peker et al. did confirm the DFS pattern by the other kit. However, the enzyme-linked immunosorbent assay (ELISA) kit they used is designed to detect the DFS70 antigen in serum. Until now, no report shows that the levels of DFS70 antigen are related with DFS70 autoantibodies, and no published studies confirmed the DFS pattern by evaluating the levels of DFS70 antigen. Moreover, Peker et al. planned to use an autoantibody testing kit for they mention in the article that DFS patterns were confirmed by specific DFS70 antibody ELISA kits. …