Expression of triggering receptor on myeloid cell 1 and histocompatibility complex molecules in sepsis and major abdominal surgery.
OBJECTIVE
To evaluate the surface expression of triggering receptor on myeloid cell 1 (TREM-1), class II major histocompatibility complex molecules (HLA-DR), and the expression of the splicing variant (svTREM-1) of TREM-1 in septic patients and those subjected to major abdominal surgery.


METHODS
Using flow cytometry, we examined the surface expression of TREM-1 and HLA-DR in peripheral blood monocytes from 11 septic patients, 7 elective gastrointestinal surgical patients, and 10 healthy volunteers. svTREM-1 levels were analyzed by RT-PCR.


RESULTS
Basal expression of TREM-1 and HLA-DR in healthy volunteers was 35.91+/-14.75 MFI and 75.8+/-18.3%, respectively. In septic patients, TREM-1 expression was 59.9+/-23.9 MFI and HLA-DR expression was 44.39+/-20.25%, with a significant difference between healthy and septic groups (P<0.05) for both molecules. In the surgical patients, TREM-1 and HLA-DR expressions were 56.8+/-20.85 MFI and 71+/-13.8% before surgery and 72.65+/-29.92 MFI and 72.82+/-22.55% after surgery. TREM-1 expression was significantly different (P = 0.0087) between the samples before and after surgery and svTREM-1 expression was 0.8590+/-0.1451 MF1, 0.8820+/-0.1460 MF1, and 2.210+/-0.7873 MF1 in the healthy, surgical (after surgery) and septic groups, respectively. There was a significant difference (P = 0.048) in svTREM-1 expression between the healthy and surgical groups and the septic group.


CONCLUSIONS
TREM-1 expression is increased during systemic inflammatory conditions such as sepsis and the postoperative phase. Simultaneous low expression of HLA-DR molecules correlates with the severity of illness and increases susceptibility to infection. Additionally, TREM-1 expression is distinctly different in surgical patients at different stages of the inflammatory response before and after surgery. Thus, surface TREM-1 appears to be an endogenous signal during the course of the inflammatory response. svTREM-1 expression is significantly increased during sepsis, appearing to be an indicator of severity of illness. Together, these data indicate that TREM-1 may play an important role in establishing and amplifying the systemic inflammatory response. TREM-1, HLA-DR, and svTREM-1 expression analysis can provide useful diagnostic and prognostic indicators during SIRS, CARS, and sepsis.
González-Roldán
Nestor
N
Unidad de Investigación Médica en Inmunoquímica, Hospital de Especialidades, Centro Médico Nacional Siglo XXI, IMSS, México.
Ferat-Osorio
Eduardo
E
Aduna-Vicente
Rosalía
R
Wong-Baeza
Isabel
I
Esquivel-Callejas
Noemí
N
Astudillo-de la Vega
Horacio
H
Sánchez-Fernández
Patricio
P
Arriaga-Pizano
Lourdes
L
Villasís-Keever
Miguel Angel
MA
López-Macías
Constantino
C
Isibasi
Armando
A
D000005:Abdomen / Q000601:surgery; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D015870:Gene Expression / Q000276:immunology; D006684:HLA-DR Antigens / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D007249:Inflammation / Q000276:immunology / Q000503:physiopathology; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D008875:Middle Aged; D011183:Postoperative Complications / Q000276:immunology / Q000503:physiopathology; D011971:Receptors, Immunologic / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D018805:Sepsis / Q000276:immunology* / Q000503:physiopathology*; D000073871:Triggering Receptor Expressed on Myeloid Cells-1
D006684:HLA-DR Antigens; D008562:Membrane Glycoproteins; D011971:Receptors, Immunologic; C408842:TREM1 protein, human; D000073871:Triggering Receptor Expressed on Myeloid Cells-1