It has been recently shown in Japanese patients with predominant salivary and lachrymal glands involvement that CD4+CD45RA−CXCR5+CCR6−CXCR3− TFH2 cells were more efficient in inducing differentiation into plasmablasts and led to higher IgG4 production by autologous naïve B cells in active, untreated IgG4-RD patients than in HC (29), suggesting a functional role of these cells in the disease. The gene discussed is CD4; the disease is immunoglobulin G4-related sclerosing disease.