SELP and systemic lupus erythematosus: In the case of P-selectin deficient mice (P-sel−/−), lack of PSGL-1/P-selectin interaction results in a systemic lupus erythematosus (SLE)-like syndrome, characterized by the production of SLE-specific autoantibodies such as anti-dsDNA or anti-RNP, reduced dermal T effector/Treg ratio, and lung and renal involvement (28).