Flow Cytometry Analysis of the Reactive Oxygen Species in Immature Granulocytes in Septic Patient (SEPSIROS)

Sepsis is life-threatening organ dysfunction caused by a dysregulated host response to infection. Early during sepsis course, immature neutrophils could be found in the bloodstream and may be less efficient than mature neutrophils in reactive oxygen species (ROS) production. ROS induce an oxidative stress for bacteria which can protect through the SOS response. The main objective is to evaluate the level of ROS produced in the early steps of sepsis by the immature neutrophils.

Study Overview

• Status: Terminated
• Conditions: Sepsis
• Intervention / Treatment: Biological: Additional blood tube

Detailed Description

Sepsis is life-threatening organ dysfunction caused by a dysregulated host response to infection. The immune system is activated by both pathogen-associated and host-derived molecular patterns. A strong response of neutrophils is engaged and both innate and adaptive immune system homeostasis are strongly affected. Neutrophils are able to produce high concentrations of inducible reactive oxygen species (ROS), leading to an oxidative stress. ROS can be released extracellularly at the site of infection or intracellularly in the phagolysosome. At early phase of sepsis, immature granulocytes are present in the bloodstream and could help to predict sepsis deterioration. However, it has also been shown that they are less efficient than mature granulocytes in ROS production and phagocytosis. ROS are potent stressors for bacteria and can directly or indirectly damage DNA. Bacteria can protect against DNA damage through the SOS response, which is a coordinated cellular response regulated by a repressor, LexA, and a sensor/activator, RecA. The bacterial SOS response is involved in acquisition of resistances to antibiotics through increasing frequencies of spontaneous mutations or increasing the expression of resistance and adaptation genes. The hypothesis that the low-level production of ROS by immature granulocytes in the early steps of sepsis could be beneficial for both the host, as a high level of ROS induce organ damage and dysfunction, and the pathogen, as low concentrations of ROS would be able to induce the SOS response allowing bacteria to enhance an adaptive response. The main objective it is to evaluate the level of ROS produced by the immature granulocytes in septic patient. Then, it will be assess if it could promote antibiotic resistance expression via SOS-induced integron gene cassette rearrangements.

• Study Type: Observational
• Enrollment (Actual): 34

Contacts and Locations

Study Locations

• France
  • Limoges, France, 87042
    • Limoges University Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

Patient hospitalized in intensive car or emergency department for acute sepsis

Description

Inclusion Criteria:

• Adult patients hospitalized in ICU or ED for acute sepsis

Exclusion Criteria:

• Immunosupressed patients
• Active cancer
• HIV
• Hematological or inflammatory diseases

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Evaluated; An additional blood tube will be taken from patients hospitalized in intensive care or emergency department for acute sepsis	Biological: Additional blood tube; Additional blood tube during care

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
ROS level by Flow cytometry in immature granulocytes dosage sepsis	The biological variable obtained is an average of fluorescence intensity (MFI) corresponding to the amount of ROS contained in the immature granulocytes from the onset of sepsis to the acute phase	Day 1

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
ROS level by Flow cytometry in mature granulocytes dosage sepsis	The biological variable obtained is an average of fluorescence intensity (MFI) corresponding to the amount of ROS contained in the mature granulocytes from the onset of sepsis to the acute phase	Day 1
Bacterial phagocytosis capacity of granulocytes assess by flow cytometry	The biological variable obtained is an average of fluorescence intensity (MFI) corresponding to the number of ingested bacteria.	Day 1
SOS response activation by bacteria determined by flow cytometry	The biological variable obtained is an average of fluorescence intensity (MFI) corresponding to the expression of the SOS gene by the bacteria.	Day 1
Hospital mortality	number of death	Day 28
ROS level by Flow cytometry in monocyte dosage sepsis	The biological variable obtained is an average of fluorescence intensity (MFI) corresponding to the amount of ROS contained in the monocyte from the onset of sepsis to the acute phase	Day 1
ROS level by Flow cytometry in lymphocyte dosage sepsis	The biological variable obtained is an average of fluorescence intensity (MFI) corresponding to the amount of ROS contained in the lymphocyte from the onset of sepsis to the acute phase	Day 1

Collaborators and Investigators

• Sponsor: University Hospital, Limoges
• Investigators: Principal Investigator: Thomas DAIX, MD, University Hospital, Limoges

Study record dates

Study Major Dates

• Study Start (Actual): March 26, 2019
• Primary Completion (Actual): March 10, 2020
• Study Completion (Actual): March 10, 2020

Study Registration Dates

• First Submitted: February 15, 2019
• First Submitted That Met QC Criteria: February 18, 2019
• First Posted (Actual): February 19, 2019

Study Record Updates

• Last Update Posted (Actual): April 8, 2020
• Last Update Submitted That Met QC Criteria: April 7, 2020
• Last Verified: April 1, 2020

More Information

Terms related to this study

• Keywords: Sepsis; reactive oxygen species; immature neutrophils
• Additional Relevant MeSH Terms: Pathologic Processes; Infections; Systemic Inflammatory Response Syndrome; Inflammation; Sepsis
• Other Study ID Numbers: 87RI18-0031 (SEPSIROS)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO