TREM-1 expression on neutrophils and monocytes of septic patients: relation to the underlying infection and the implicated pathogen
1 4th Department of Internal Medicine, University of Athens, Medical School, ATTIKON General Hospital, 1 Rimini Str., 12462 Athens, Greece
2 2nd Department of Critical Care, University of Athens, Medical School, ATTIKON General Hospital, 1 Rimini Str., 12462 Athens, Greece
3 1st Department of Internal Medicine, "Thriasion" Elefsina General Hospital, Leoforos Gennimata, 19600 Magoula, Greece
4 2nd Department of Urology, "Sismanogleion" Athens Hospital, 1 Sismanogleiou Str., 15126 Maroussi, Greece
5 Intensive Care Unit, "Ippokrateion" Athens General Hospital, 114 Vassilis Sofias Str., 11527 Athens, Greece
6 2nd Department of Surgery, University of Thessaloniki, Medical School, 41 Ethnikis Aminis Str., 54635 Thessaloniki, Greece
7 2nd Department of Internal Medicine, "Sismanogleion" Athens Hospital, 1 Sismanogleiou Str., 15126 Maroussi, Greece
8 Intensive Care Unit, "Laikon" Athens General Hospital, 17 Aghiou Thoma Str., 11527 Athens, Greece
9 Department of Plastic Surgery, 251 Air Force General Hospital, 3 Kanellopoulou Str, 112527 Athens, Greece
10 Intensive Care Unit, "Aghia Olga" Athens General Hospital, 3-5 Aghia Olga Str., 14233 Nea Ionia, Greece
11 3rd Department of Pulmonary Medicine, "Sismanoglion" Athens Hospital, 1 Sismanogleiou Str., 15126 Maroussi, Greece
BMC Infectious Diseases 2011, 11:309 doi:10.1186/1471-2334-11-309Published: 4 November 2011
Current knowledge on the exact ligand causing expression of TREM-1 on neutrophils and monocytes is limited. The present study aimed at the role of underlying infection and of the causative pathogen in the expression of TREM-1 in sepsis.
Peripheral venous blood was sampled from 125 patients with sepsis and 88 with severe sepsis/septic shock. The causative pathogen was isolated in 91 patients. Patients were suffering from acute pyelonephritis, community-acquired pneumonia (CAP), intra-abdominal infections (IAIs), primary bacteremia and ventilator-associated pneumonia or hospital-acquired pneumonia (VAP/HAP). Blood monocytes and neutrophils were isolated. Flow cytometry was used to estimate the TREM-1 expression from septic patients.
Within patients bearing intrabdominal infections, expression of TREM-1 was significantly lower on neutrophils and on monocytes at severe sepsis/shock than at sepsis. That was also the case for severe sepsis/shock developed in the field of VAP/HAP. Among patients who suffered infections by Gram-negative community-acquired pathogens or among patients who suffered polymicrobial infections, expression of TREM-1 on monocytes was significantly lower at the stage of severe sepsis/shock than at the stage of sepsis.
Decrease of the expression of TREM-1 on the membrane of monocytes and neutrophils upon transition from sepsis to severe sepsis/septic shock depends on the underlying type of infection and the causative pathogen.