Validation of leukotriene B4 measurements in exhaled breath condensate.
OBJECTIVE
To qualitatively validate an enzyme immunoassay to measure leukotriene B4 in exhaled breath condensate. Exhaled breath condensate is a new non-invasive method to monitor airway inflammation.


METHODS
Twenty-two subjects with different lung diseases attended the outpatient clinic on one occasion for exhaled breath condensate collection.


METHODS
Samples were pooled together and purified by reverse-phase high-performance liquid chromatography. The fractions eluted were assayed for leukotriene B4 by enzyme immunoassay.


RESULTS
A single peak of leukotriene B4-like immunoreactivity co-eluting with leukotriene B4 standard (retention time: 24 min) was identified by enzyme immunoassay. Reverse phase-high performance liquid chromatography peak of leukotriene B4 was clearly separated from those of 6-trans-leukotriene B4 (retention time: 14 min) and leukotriene B5 (retention time: 18 min) for which the antiserum used in the enzyme immunoassay had the highest cross-reactivity. Leukotriene B4 recovery was 64%.


CONCLUSIONS
This study provides evidence for the presence of leukotriene B4 in the exhaled breath condensate and the specificity of the enzyme immunoassay used.
Montuschi
P
P
Department of Pharmacology, Catholic University of the Sacred Heart, L.go F. Vito, 1, Roma, Italy. p.montuschi@ic.ac.uk
Ragazzoni
E
E
Valente
S
S
Corbo
G
G
Mondino
C
C
Ciappi
G
G
Barnes
P J
PJ
Ciabattoni
G
G
D001944:Breath Tests; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques / Q000592:standards; D007975:Leukotriene B4 / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity
D007975:Leukotriene B4