Cytokine concentrations in exhaled breath condensates in systemic sclerosis.
BACKGROUND
Pulmonary fibrosis in systemic sclerosis (SSc) involves inflammatory processes in the lower respiratory tract. Analysis of exhaled breath condensate (EBC) is a non-invasive method for studying inflammatory mediators, such as cytokines, which are of interest from both physiological and therapeutic perspectives. The aim of this study was to assess and compare cytokine concentrations in the EBC of SSc patients and controls.


METHODS
EBC was collected from 19 SSc patients and 19 controls. We used a multiplex assay test kit to assay interleukin (IL)-2, -4, -6, -10, tumour necrosis factor-alpha, and interferon-gamma in samples concentrated by lyophilization.


RESULTS
Cytokine concentrations in EBC were higher in SSc patients than in controls. The stepwise analyses showed that IL-4 was the biomarker which contributed most to the discrimination between controls and patients (Wilk's Lambda = 0.55, p < 0.001). We observed significant negative correlations of EBC cytokines with total lung capacity and diffusion capacity of the lung for carbon monoxide.


CONCLUSIONS
These findings suggest that EBC sampling permits the non-invasive study of inflammation in SSc patients, and may be correlated with the severity of interstitial lung disease.
Edmé
J L
JL
EA Toxiques et cancérogènes professionnels (EA 2690) - CERESTE, Université de Lille 2, Lille, France. jledme@univ-lille2.fr
Tellart
A S
AS
Launay
D
D
Neviere
R
R
Grutzmacher
C
C
Boulenguez
C
C
Labalette
M
M
Hachulla
E
E
Hatron
P Y
PY
Dessaint
J-P
JP
Matran
R
R
Sobaszek
A
A
D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000378:metabolism; D001944:Breath Tests; D002248:Carbon Monoxide / Q000378:metabolism; D016022:Case-Control Studies; D016207:Cytokines / Q000378:metabolism*; D045853:Exhalation / Q000502:physiology*; D006801:Humans; D015847:Interleukin-4 / Q000378:metabolism; D008168:Lung / Q000378:metabolism / Q000503:physiopathology; D008875:Middle Aged; D012595:Scleroderma, Systemic / Q000378:metabolism* / Q000503:physiopathology; D012720:Severity of Illness Index
D015415:Biomarkers; D016207:Cytokines; D015847:Interleukin-4; D002248:Carbon Monoxide