To assess if this pro-apoptotic role for SLE autoantibodies in this in vitro H/R was dependent on the presence of APS-related autoantibodies, further experiments were performed using another marker of apoptosis, cleaved caspase-3 and an expanded set of patient IgG samples allowing groups to be compared between those that are SLE/APS positive versus SLE/APS negative and APS alone. This evidence concerns the gene CASP3 and systemic lupus erythematosus.