Hemophagocytic macrophages constitute a major compartment of heme oxygenase expression in sepsis.

Abstract

OBJECTIVES:

Uncontrolled macrophage activation with hemophagocytosis is a distinctive feature of hemophagocytic syndromes (HPS). We examined whether lympho-histiocytic infiltration of the bone marrow and liver, as well as hemo-/erythrophagocytosis also occurs during sepsis and whether this process could account for the increased production of anti-inflammatory heme-oxygenase (HO-1) products observed during sepsis.

METHODS:

Hemophagocytosis and expression of CD163, HO-1, ferritin as well as CD8 and granzyme-B were examined in post-mortem bone marrow samples from 28 patients with sepsis and from eight control patients.

RESULTS:

Comparison of samples from non-septic patients with samples from patients with fatal sepsis revealed that the latter group displayed dense lympho-histiocytic bone marrow infiltration with CD163(+)/HO-1(+)/ferritin(+) macrophages as well as with CD8(+) and granzyme-B(+) T-cells. Hemophagocytosis with prominent phagocytosis of erythroid cells was readily apparent in septic patients, implying that this process is a likely stimulus for the up-regulation of macrophage HO-1 expression.

CONCLUSIONS:

Lympho-histiocytic activation with hemophagocytosis is a shared pathophysiologic mechanism in HPS and sepsis. Furthermore, the association of hemophagocytosis with an increase in HO-1 expression may indicate a novel role for this apparently futile process as a negative regulator of inflammation.

• Authors: Dominik J Schaer, Christian A Schaer, Gabriele Schoedon, Alexander Imhof, Michael O Kurrer
• Journal: European journal of haematology (Eur J Haematol) Vol. 77 Issue 5 Pg. 432-6 (Nov 2006) ISSN: 0902-4441 [Print] England
• PMID: 17044836 (Publication Type: Comparative Study, Journal Article)

Chemical References

• Biomarkers
• Heme Oxygenase-1

Topics

• Adult
• Aged
• Aged, 80 and over
• Biomarkers (metabolism)
• Bone Marrow (enzymology, metabolism, pathology)
• Erythroid Cells (enzymology, pathology)
• Female
• Gene Expression Regulation, Enzymologic (genetics)
• Heme Oxygenase-1 (biosynthesis, genetics)
• Humans
• Liver (enzymology, pathology)
• Macrophages (enzymology, pathology)
• Male
• Middle Aged
• Phagocytosis (genetics)
• Sepsis (enzymology, genetics, pathology)
• Up-Regulation (genetics)