CD4+T cells play a well-documented role in the dysregulated immune response observed in RA, with a potential role for dysfunctional regulatory T cells (Tregs) as well as atypical effector T cells.15 16 To this end we have taken advantage of an inception cohort of patients with newly diagnosed RA starting MTX to profile peripheral blood CD4+T cell protein and gene expression and explore putative biomarkers for MTX response.9 17–19 This work forms part of a larger discovery cohort investigating early therapy in RA. The gene discussed is CD4; the disease is rheumatoid arthritis.