5 Therefore, the aim of this study was to clarify the impact of Treg in the acute phase of ischemic stroke by the means of a superagonistic anti-CD28 antibody (CD28 SA) that leads to an expansion of pre-existing Treg in the lymphoid organs and the dissemination of increased Treg numbers in the peripheral blood.9,10. The gene discussed is CD28; the disease is ischemic stroke.