CTLA4 and Autoimmunity: Consistent with this correlation of CTLA-4 pathway disruption, ipilimumab-treated patients demonstrate the highest CTLA4 mRNA expression levels compared to the monogenic patients or healthy controls; particularly, the ipilimumab-treated patients who developed autoimmunity were those who had the highest CTLA4 mRNA expression (most CTLA-4 pathway disruption).