Concentration of 14,15-leukotriene C4 (eoxin C4) in bronchoalveolar lavage fluid.
BACKGROUND
There has been no information about the concentration of 14,15-leukotriene C4, which is generated by 15- and 12-lipoxygenase and has been recently named eoxin C4, in biological fluids.


OBJECTIVE
To determine the clinical concentrations of eoxin C4 in various respiratory inflammatory diseases, we quantified eoxin C4 in relation to the concentrations of cysteinyl-leukotrienes (CysLTs) and 15-hydroxyeicosatetraenoic acid (15-HETE) in bronchoalveolar lavage fluid (BALF).


METHODS
BALF fluid was obtained from patients with a number of inflammatory lung diseases. Eoxin C4 and CysLTs were quantified by enzyme immunoassay in combination with high-performance liquid chromatography. Eoxin C4 immunoassay does not detect eoxin D4 or eoxin E4. 15-HETE was quantified by gas chromatography-mass spectrometry using (18)O-labeled compounds as an internal standard.


RESULTS
The concentration of eoxin C4 (median 1.4, range <1.12-6.7 pg/mL) was significantly lower than that of eoxin C4 or CysLTs (P<0.0001). The concentration of 15-HETE significantly correlated with those of LTC4 and CysLTs or the number and the percentage of eosinophils in BALF. On the other hand, eoxin C4 concentration did not correlate with eosinophil number or CysLTs concentration in BALF.


CONCLUSIONS
This is the first study demonstrating the presence of eoxin C4 in human biological fluids. Further studies are necessary to elucidate the pathophysiological role of eoxin C4 in some respiratory inflammatory diseases.
Ono
E
E
Clinical Research Center for Allergy and Rheumatology, National Hospital Organization, Sagamihara National Hospital, Sagamihara, Kanagawa, Japan. onoemii@e-ml.jp
Mita
H
H
Taniguchi
M
M
Higashi
N
N
Hasegawa
M
M
Miyazaki
E
E
Kumamoto
T
T
Akiyama
K
K
D001092:Arachidonate 12-Lipoxygenase / Q000378:metabolism; D001093:Arachidonate 15-Lipoxygenase / Q000378:metabolism; D001992:Bronchoalveolar Lavage Fluid; D002851:Chromatography, High Pressure Liquid; D005260:Female; D006801:Humans; D007118:Immunoassay; D017997:Leukotriene C4 / Q000032:analysis / Q000378:metabolism; D015289:Leukotrienes / Q000032:analysis / Q000378:metabolism*; D008171:Lung Diseases / Q000378:metabolism*; D008297:Male
D015289:Leukotrienes; C526311:eoxin C4; D017997:Leukotriene C4; D001092:Arachidonate 12-Lipoxygenase; D001093:Arachidonate 15-Lipoxygenase