Lack of recovery in monocyte human leukocyte antigen-DR expression is independently associated with the development of sepsis after major trauma

Abstract

IntroductionMajor trauma is characterized by an overwhelming pro-inflammatory response and an accompanying anti-inflammatory response that lead to a state of immunosuppression, as observed after septic shock. Diminished monocyte Human Leukocyte Antigen DR (mHLA-DR) is a reliable marker of monocyte dysfunction and immunosuppression. The main objective of this study was to determine the relation between mHLA-DR expression in severe trauma patients and the development of sepsis.MethodsWe conducted a prospective observational study over 23 months in a trauma intensive care unit at a university hospital. Patients with an Injury Severity Score (ISS) over 25 and age over 18 were included. mHLA-DR was assessed by flow cytometry protocol according to standardized protocol. Mann-Whitney U-test for continuous non-parametric variables, independent paired t test for continuous parametric variables and chi-square test for categorical data were used.ResultsmHLA-DR was measured three times a week during the first 14 days. One hundred five consecutive severely injured patients were monitored (ISS 38 ± 17, SAPS II 37 ± 16). Thirty-seven patients (35%) developed sepsis over the 14 days post-trauma. At days 1-2, mHLA-DR was diminished in the whole patient population, with no difference with the development of sepsis. At days 3-4, a highly significant difference appeared between septic and non-septic patients. Non- septic patients showed an increase in mHLA-DR levels, whereas septic patients did not (13,723 ± 7,766 versus 9,271 ± 6,029 antibodies per cell, p = .004). Most importantly, multivariate logistic regression analysis, after adjustment for usual clinical confounders (adjusted OR 5.41, 95% CI 1.42-20.52), revealed that a slope of mHLA-DR expression between days1-2 and days 3-4 below 1.2 remained associated with the development of sepsis.ConclusionsMajor trauma induced an immunosuppression, characterized by a decrease in mHLA-DR expression. Importantly, after multivariate regression logistic analysis, persistent decreased expression was assessed to be in relation with the development of sepsis. This is the first study in trauma patients showing a link between the lack of immune recovery and the development of sepsis on the basis of the standardized protocol. Monitoring immune function by mHLA-DR measurement could be useful to identify trauma patients at a high risk of infection.

Inter‐laboratory assessment of flow cytometric monocyte HLA‐DR expression in clinical samples

“…Comparison of FC500 (alternate protocol) and Navios (standardized protocol) results in a same laboratory. 47 blood samples from patients (12 HIV-infected and 17 ICU patients) and 13 healthy donors were either treated according to homemade staining procedure (11) or the standardized protocol (13). Cells were washed after staining.…”

“…Briefly, whole blood (50 lL) was stained with 20 lL of QuantiBrite HLA-DR/Monocyte mixture (QuantiBrite anti-HLA-DR PE (clone L243)/Anti-monocytes (CD14) PerCP-Cy5.5 (clone MUP9), Becton Dickinson San Jose, CA, USA) at room temperature for 30 min in a dark chamber. Alternatively, cells were stained with FITC-labeled anti-CD14 (BeckmanCoulter, Miami, FL) and PE-labeled anti-HLA-DR (clone L243, Becton DickinsonPharmingen, San Jose, CA) at room temperature for 30 min in a dark chamber according to a previously used protocol (thereafter called ''alternate protocol" (11)). Samples were then lysed using the FACS Lysing solution (Becton Dickinson) for 15 min.…”

“…In a previous study (11), we set up a homemade protocol based on the same principle as the standardized procedure for mHLA-DR measurement (i.e., monocyte identification through CD14 expression / PE-HLA-DRclone L243, Becton for HLA-DR expression measurement and QuantiBrite beads for calculation of AB/C) but without using the ready-to-use QuantiBrite mixture. As a first step, we compared this protocol run on a FC500 flow cytometer to the standardized protocol run on a Navios analyzer.…”

“…In terms of functionality, monocytes with low HLA-DR expression are known to be unable to mount a pro-inflammatory response to any subsequent bacterial challenge or to properly present antigens to T cells (2,7). In terms of clinical information, decreased mHLA-DR has been shown to be predictive of both adverse outcome and septic complications after trauma, surgery, pancreatitis, burn, and septic shock (8)(9)(10)(11).…”

Are there new approaches for diagnosis, therapy guidance and outcome prediction of sepsis?

“…Decreased mHLA-DR levels could predict poor outcome and septic Kojic D et al . A review "from bench to bedside" complications after trauma, surgery, burn, pancreatitis and septic shock [86][87][88][89] but there is few knowledge about the underlying mechanisms [90] . A prospective randomised placebo-controlled trial used mHLA-DR to stratify the administration of granulocytemacrophage colony-stimulating factor (GM-CSF) in a small group of septic patients.…”