Although intracellular GM-CSF expression by ST polyfunctional lymphocytes (Th1, Th17, and ex-Th17 subtypes) have been reported using flow cytometry in PsA and the number of these cells correlated with the disease activity of psoriatic arthritis score (DAPSA) (53), we could not confirm GM-CSF expression by CD3+ or CD4+ T cells in our samples. Here, CD4 is linked to psoriatic arthritis.