The present study is the first to demonstrate that: (1) PECAM1 expression is modulated in the lungs in response to MV in the presence or absence of sepsis; (2) the expression of PECAM1 is dependent on the MV regime applied; and (3) the circulating levels of sPECAM1 are rapidly and markedly increased during injurious MV. Here, PECAM1 is linked to Sepsis.