 The T-SPOT assay quantifies the number of peripheral blood interferon-γ producing effector T cells spot forming cellsmillion peripheral blood mononuclear cells - PBMC. The T-SPOT platform technology can be applied to diagnose and monitor any major disease process driven by a T cell response, including a viral disease such as cytomegalovirus CMV infection the T-SPOT.CMV assay or an allograft rejection the T-SPOT.PRT assay. 