CTLA4 and synovial sarcoma: In C57BL/6.NOD-Aec1Aec2 mice, another model for SS, treatment with an adeno-associated virus-2 vector encoding a CD152-Ig fusion protein reduced cell infiltration and Th1 and Th17 cytokine production [113], probably by binding to CD80 and CD86 and preventing co-stimulation through CD28.