FAS and autoimmune lymphoproliferative syndrome: The defective Fas gene-mediated decreased functionality of regulatory T cells, accumulation of Th1 biased lymphocytes, and accumulation of anti-nucleic acid antibody-producing B lymphocytes drive an aggressive autoimmune phenotype relevant to many human autoimmune diseases including lupus, Sjogren’s syndrome, arthritis, and autoimmune lymphoproliferative syndrome (ALPS)32–35.