Intracellular monocyte cytokine production and CD 14 expression are up-regulated in severe vs mild chronic heart failure.
BACKGROUND
The role of circulating monocytes in the process of low-grade inflammation, characteristic of chronic heart failure (CHF), has recently been questioned. Lipopolysaccharide (LPS) desensitization has been proposed to mediate reduced monocyte cytokine elaboration in patients with severe CHF.


METHODS
Intracellular monocyte production of interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6) and tumor necrosis factor (TNF)-alpha, and monocyte CD 14 expression were measured flow-cytometrically without and after 8-hour LPS stimulation in 46 patients with CHF and in a healthy control group.


RESULTS
Basal cytokine concentrations were similar for the control and the mild CHF groups (New York Heart Association [NYHA] Class I or II). After LPS stimulation, IL-6 (p=0.002) and TNF-alpha levels (p=0.001) were lower in the latter group, whereas IL-1 beta production was comparable. For the moderate-severe CHF patients, unstimulated IL-1 beta (p=0.04) was higher, whereas IL-6 (p=0.2) and TNF-alpha (p=0.1) levels were not different from the controls. Measurement of LPS-stimulated cytokine production showed no differences between the control group and patients with moderate-severe CHF (all p= 0.5). Upon comparing mild vs moderate-severe CHF patients, higher levels of unstimulated cytokine production (IL-1 beta, p=0.002; IL-6, p=0.01; TNF-alpha, p=0.003), stimulated IL-1 beta (p=0.002) and IL-6 (p=0.008) were found in the latter patients. CD 14 expression in the moderate-severe CHF group was higher than in the mild-CHF group (p = 0.03) and was strongly related to stimulated IL-1 beta (r=0.62, p<0.0001), IL-6 (r=0.56, p=0.0002) and TNF-alpha (r=0.41, p=0.006) production.


CONCLUSIONS
CD 14 expression and monocyte cytokine production, both unstimulated and after LPS stimulation, are increased in moderate-severe CHF when compared with mild CHF. These data suggest that circulating monocytes, possibly via increased CD 14 expression, may play a significant role in the immunologic dysbalance observed in advanced CHF.
Department of Cardiology, University Hospital Antwerp (UIA), Antwerp, Belgium. viviane.conrads@uza.be
Viviane M
VM
Conraads
Johan M
JM
Bosmans
Annemie J
AJ
Schuerwegh
Inge
I
Goovaerts
Luc S
LS
De Clerck
Wim J
WJ
Stevens
Chris H
CH
Bridts
Christiaan J
CJ
Vrints
D016207:Cytokines / Q000096:biosynthesis / Q000378:metabolism*; D005260:Female; D006333:Heart Failure / Q000097:blood / Q000378:metabolism*; D006801:Humans; D015850:Interleukin-6 / Q000096:biosynthesis; D018950:Lipopolysaccharide Receptors / Q000096:biosynthesis*; D008070:Lipopolysaccharides; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000378:metabolism*; D047888:Receptors, Tumor Necrosis Factor, Type I / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D048069:Tumor Necrosis Factors / Q000378:metabolism
D016207:Cytokines; D015850:Interleukin-6; D018950:Lipopolysaccharide Receptors; D008070:Lipopolysaccharides; D047888:Receptors, Tumor Necrosis Factor, Type I; D014409:Tumor Necrosis Factor-alpha; D048069:Tumor Necrosis Factors