This document summarizes the mechanisms of systemic lupus erythematosus (SLE). It discusses genetic and environmental risk factors for SLE, including a stronger prevalence in females which implicates a role for sex hormones. It describes the diverse clinical presentations of SLE and important autoantibodies involved, such as anti-double stranded DNA antibodies. The document also discusses how these autoantibodies can cause tissue damage by binding to antigens in organs and activating the complement system, as seen in lupus nephritis. Overall, it provides an overview of the pathogenesis of SLE by involving genetic, environmental, and immunological factors.