CD4 and systemic lupus erythematosus: [15] In the present work we demonstrate that the polyfunctionality index assigns larger values to IL-22-secreting CD4+ T cells than IL-17A+IL-22− CD4+ T cells, indicating that the former are the more polyfunctional. In another previous study we monitored the functional capacity of EBV-specific CD8+ T cells in SLE patients and healthy controls. [11] We demonstrated that EBV-specific CD8+ T cells from SLE patients have an aberrant polyfunctionality profile compared to healthy controls, when measuring IFN-γ-, TNF-α-, IL-2- and MIP-1β-secretion as functional parameters.