IL21 and systemic lupus erythematosus: Further research has shown that ROCK activity is elevated in peripheral blood mononuclear cells (PBMCs) from patients with SLE and RA and that the production of IL-17 and IL-21 by SLE T cells or Th17 cells can be inhibited by targeting the RhoA/ROCK pathway via both non-selective and selective approaches (Rozo et al., 2017).