Blood signatures have also been obtained from solid organ transplant recipients in the context of both tolerance [97] [98] [99] and graft rejection [10, 100, 101] . While such signatures can also be detected in biopsy material [102] [103] [104] , blood off ers the distinct advantage of being accessible for safely monitoring molecular changes on a routine basis. Some work has also been done in the context of cardiovascular diseases where infl ammation is known to play an important role. Hence, profi les have been identifi ed in a wide range of conditions, including stroke, chronic heart failure or acute coronary syndrome [105] [106] [107] [108] .