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Pathophysiology and Clinical Relevance of Endotoxin Tolerance in Humans

Phase 1
Completed
Conditions
Endotoxemia
Registration Number
NCT00246714
Lead Sponsor
Radboud University Medical Center
Brief Summary

A number of diseases lead to a so called systemic inflammatory response syndrome (SIRS). This excessive response is self-destructive and leads to major complications of the initial disease: dysfunction of the microcirculation, systemic vasodilation, and increased capillary leakage and oedema. Animal studies have shown that pre-treatment with endotoxin (lipopolysaccharide or LPS) suppress the excessive immune response and when rechallenged, the animal survive a normally lethal dose of endotoxin.

Besides a diminished cytokine response, an increased production of leucocytes in the bone marrow and an increased phagocytosis after pre-treatment with endotoxin is seen. The combination of these factors: diminished systemic inflammatory response and increased cellular immunity makes that endotoxin tolerance is a useful tool for preventing the complications after an excessive inflammatory response.

Further, the presence of cross-tolerance has also been shown: Endotoxin tolerant mice survive more after induction of a normally lethal fungal infection. Endotoxin tolerance is also protective for ischemia/reperfusion injury in kidneys, heart and liver. Little data is known about endotoxin tolerance in human.

The purpose of this study is to induce a state of tolerance through 2 different administration schedules and monitor the effect of tolerance on pro- and anti-inflammatory cytokines, other inflammatory parameters and different proteins involved in the signalling pathway. The effects of tolerance on vascular reactivity will be determined. Finally, the effect of tolerance on ischemia-reperfusion injury will be investigated.

Detailed Description

See protocol

Recruitment & Eligibility

Status
COMPLETED
Sex
Male
Target Recruitment
16
Inclusion Criteria
  • Healthy male volunteers
Exclusion Criteria
  • drug-, nicotine-, alcohol abuses
  • tendency towards fainting
  • BMI < 18 kg/m2

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Primary Outcome Measures
NameTimeMethod
inducing endotoxin tolerance5 days
Hemodynamics5 days
Markers of Inflammation5 days
Cytokines5 days
Mediators of Vascular reactivity5 days
Sensitivity to norepinephrine5 days
Endothelial-dependent vasorelaxation5 days
Cross tolerance6 days
Ischemia-reperfusion injury6 days
Effects on tissue saturation (measured by NIRS)24 hrs after LPS administration
Secondary Outcome Measures
NameTimeMethod

Trial Locations

Locations (1)

Radboud University Nijmegen Medical Center

🇳🇱

Nijmegen, Gelderland, Netherlands

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