CD4 and systemic lupus erythematosus: Endogenous peptide epitopes of histones from nucleosomes induce immune tolerance and promote CD4+ and CD8+ Treg responses, and reduce lupus nephritis and B cell activation in (SWR x NZB) F1 (SNF1) mice,[70, 71, 72] also blocking pathogenic autoimmunity in human SLE.[73,74]