Role of Circulating Cytotoxic Lymphocytes in Endothelial Cell Injury in Systemic Sclerosis

Systemic Sclerosis (SSc) is an auto-immune systemic disease characterized by vascular damage, cutaneous and visceral fibrosis and a dysimmune condition. Therapies in this disease remain insufficient and the complications resulting from organs involvement lead to strong morbi-mortality.The dermic infiltrate of the patients includes a strong proportion of Tcells. T cells and Natural Killer (NK) cells are potentially involved in the vascular damage of the SSc. However mechanisms at the onset of this endothelial cytotoxicity and its impact on the capacities of regeneration of the endothelial tissue remain poorly understood. Fractalkine is at the same time an endothelial membrane-bound adhesion molecule and a chemokine which is able to bind CX3CR1 expressed by the immune populations. The purpose of the project is to define the role displayed by cytotoxic, circulating immune populations of SSc patients in endothelial cytotoxicity as well as the role of the axis Fractalkine / CX3CR1 in mediating the interactions between the immune cytotoxic cells and the endothelium.