Figure 4From: TAM receptor ligands in lupus: Protein S but not Gas6 levels reflect disease activity in systemic lupus erythematosusLevels of free protein S according to the presence of autoantibodies in SLE. Free protein S in patients with (a) anti-Sm and (b) anticardiolipin (ACA). SLE, systemic lupus erythematosus.Back to article page