The Effects of Human Endotoxemia on Functional Capacity of Hematopoietic Stem and Progenitor Cells (LPS-BM)

We will investigate whether human endotoxemia induces changes in human bone marrow cells and their downstream effector cells. To comprehensively investigate underlying mechanisms behind functional and transcriptional changes in these cell types, we will use state-of-the-art systems biology techniques, including single cell transcriptomics (epi)genetics, and metabolomics.

Study Overview

• Status: Completed
• Conditions: Sepsis, Endotoxemia, Immunosuppression
• Intervention / Treatment: Drug: LPS; Drug: Placebo

Detailed Description

In the present study, we want to further elucidate the mechanisms behind systemic inflammation and endotoxin tolerance in vivo in humans by focusing on functional changes in hematopoietic stem and progenitor cells. Healthy male volunteers will be challenged with endotoxin to evoke a transient systemic inflammatory response. To evaluate the responses over time, blood and bone marrow aspirates will be collected at multiple timepoints. To comprehensively investigate underlying mechanisms behind functional changes, we will use state-of-the-art systems biology techniques, including single cell transcriptomics, epigenetics (e..g. scATACseq), and metabolomic. As such, this study will yield a comprehensive insight into inflammatory signaling in the different compartments of the body and will thereby improve our understanding of systemic inflammation, endotoxin tolerance,and sepsis, possibly revealing new therapeutic targets to improve sepsis outcome.

• Study Type: Interventional
• Enrollment (Actual): 12
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Netherlands
  • Gelderland
    • Nijmegen, Gelderland, Netherlands, 6500 HB
      • Intensive Care Medicine, Radboud University Nijmegen Medical Centre

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years to 33 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Male

Description

Inclusion Criteria:

• Written informed consent
• Age ≥18 and ≤35 yrs
• Male
• Healthy (as confirmed by medical history, examination, ECG, blood sampling)

Exclusion Criteria:

• Use of any medication
• Smoking
• History or signs of atopic syndrome (asthma, rhinitis with medication and/or eczema)
• Known anaphylaxis or hypersensitivity to the non-investigational products or their excipients.
• History or signs of hematological disease (bone marrow dysfunction):
• Thrombocytopenia (<150*10^9/ml) or anemia (hemoglobin < 8.0 mmol/L)
• Abnormalities in leukocyte differential counts
• History, signs or symptoms of cardiovascular disease, in particular:
• Previous spontaneous vagal collapse
• History of atrial or ventricular arrhythmia
• Cardiac conduction abnormalities on the ECG consisting of a 2nd degree atrioventricular block or a complete left bundle branch block
• Hypertension (defined as RR systolic > 160 or RR diastolic > 90)
• Hypotension (defined as RR systolic < 100 or RR diastolic < 50)
• Renal impairment (defined as plasma creatinine >120 μmol/l)
• Liver enzyme abnormalities (above 2x the upper limit of normal)
• Medical history of any disease associated with immune deficiency
• CRP > 20 mg/L, WBC > 12x109/L or < 4 x109/L, or clinically significant acute illness, including infections, within 3 weeks before labeling day
• Previous (participation in a study with) LPS administration
• Any vaccination within 3 months prior to labeling day
• Participation in a drug trial or donation of blood 3 months prior to labeling day
• Recent hospital admission or surgery with general anesthesia (<3 months to labeling day)
• Use of recreational drugs within 21 days prior to labeling day
• Inability to personally provide written informed consent (e.g. for linguistic or mental reasons) and/or take part in the study.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: LPS group; Healthy male volunteers that will receive an intravenous administration of LPS (2ng/kg) twice.	Drug: LPS; This is a non-investigational product. LPS is used as challenge agent to achieve a controlled inflammatory state.; Other Names: Lipopolysaccharide (LPS from Escherichia coli Type O11); Endotoxin
Placebo Comparator: Placebo group; Healthy male volunteers that will receive an intravenous administration of placebo (NaCl 0.9%).	Drug: Placebo; Injection of NaCl 0.9%.; Other Names: NaCl

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in function and transcriptional pathways	The change in function and transcriptional pathways (gene expression) of hematopoietic progenitor cells and blood leukocytes (using various functional assays and single cell RNAseq) following human endotoxemia.	15 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in (Genome-wide) chromatin accessibility	The change in epigenomic profile (chromatin accessibility) of hematopoietic progenitor cells and blood leukocytes (using single cell ATACseq) following human endotoxemia.	15 days
Change in cellular metabolism	The change in cellular metabolism of hematopoietic progenitor cells and blood leukocytes (e.g. using Seahorse analyzer, CYTOF) following human endotoxemia.	15 days
Change in macrophage activity in the brain	To changes in tissue resident macrophages activity in the brain (assessed using 18F-DPA-714 labeling and PET examinations) following human endotoxemia.	15 days
Life-span of blood leukocytes during homeostasis	To assessment of the life-span and transit times of different subsets of leukocytes and their progenitors in the bone marrow of humans at homeostasis (using Deuterium labeling).	8 days
Life-span of blood leukocytes during endotoxemia	To determine the life-span and transit times of different subsets of leukocytes and their progenitors in the bone marrow of humans during human endotoxemia (using Deuterium labeling).	8 days

Collaborators and Investigators

• Sponsor: Radboud University Medical Center
• Collaborators: UMC Utrecht

Study record dates

Study Major Dates

• Study Start (Actual): January 5, 2018
• Primary Completion (Actual): June 28, 2018
• Study Completion (Actual): June 28, 2018

Study Registration Dates

• First Submitted: September 28, 2022
• First Submitted That Met QC Criteria: October 4, 2022
• First Posted (Actual): October 6, 2022

Study Record Updates

• Last Update Posted (Actual): October 6, 2022
• Last Update Submitted That Met QC Criteria: October 4, 2022
• Last Verified: September 1, 2022

More Information

Terms related to this study

• Keywords: Sepsis, immunosuppression, systemic inflammation, human endotoxemia, bone marrow stem and progenitor cells, myelopoiesis, monocytes, transciptomics
• Additional Relevant MeSH Terms: Pathologic Processes; Infections; Systemic Inflammatory Response Syndrome; Inflammation; Sepsis; Bacteremia; Toxemia; Endotoxemia
• Other Study ID Numbers: NL61136.091.17; 2017-3337 (Other Identifier: METC Oost Nederland (Ethical Board))

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: Yes
• IPD Plan Description: Single cell transcriptional/gene expression data will be shared.

IPD Sharing Access Criteria

Bulk RNA-seq and scRNA-seq data for this study can be downloaded from GEO database (https://www.ncbi.nlm.nih.gov/geo/) with the accession number: GSE212093.

Codes used to perform the data analysis related to this study are available at https://github.com/fkeramati/LPS-SI

• IPD Sharing Supporting Information Type: Statistical Analysis Plan (SAP); Analytic Code

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: Yes