PRF1 and systemic lupus erythematosus: The studies from this group also identified numerous lupus-related genes including integrin subunit α L (ITGAL, or CD11a) [44], CD40 ligand (CD40LG) [45], tumor necrosis factor ligand superfamily 7 (TNFSF7 or CD70) [46], and perforin (PRF1) [47], which are hypomethylated in human lupus T cells, correlating with the overexpression of these genes in SLE patients.