Background:
Airway remodeling
has recently emerged
as a major problem
in an increasing
percentage of
patients with asthma.
Reasons for great
diversity in the
progression of
irreversible
bronchoconstriction
among asthmatics
remain unclear.
Objective:
The aim of this
study was to assess
whether the
potential ability of
leukocytes to
produce cysteinyl
leukotrienes in
response to various
stimuli is
correlated with
magnitude of
irreversible airway
obstruction in
asthmatics.
Materials and
Methods: The
study sample
comprised 76
asthmatics (34
males, mean ± SD age
52 ± 13 years), and
35 healthy controls
(18 males, 38.2 ± 15
years). Each subject
underwent 2
pulmonary function
tests: before and
after bronchodilator
administration. In
addition,
approximate annual
decline in forced
expiratory volume in
1 second (FEV1) (%
of predicted) was
calculated.
Leukotriene C4
(LTC4) production
was assessed
combining a cellular
antigen stimulation
test and enzyme-linked
immunosorbent assay
using Bulhmann
Laboratories AG kits.
Leukocytes isolated
from peripheral
blood were
stimulated with anti-FcεRI
antibody, N-formyl-methionyl-leucyl-phenylalanine
(fMLP) and
phorbol 12-myristate
13-acetate (PMA). In
separate tubes each
subjects leukocytes
were tested for
spontaneous LTC4
production. Finally,
stimulated LTC4
production was
expressed in pg/mL
after subtraction of
values of
spontaneous
production.
Results: In
asthmatics, baseline
FVC% and FEV1%
values ranged from
24.4% to 122.4%
(mean, 75.5%) and
from 23.4% to 126.6%
(mean, 74.4%),
respectively. There
were no signifi cant
differences between
asthmatics and
controls in LTC4
production
stimulated by
anti-FcεRI antibody
(P = .79), fMLP (P =
.33) or PMA (P =
.86). We found no
correlation between
stimulated LTC4
production and
spirometric
parameters at
baseline or after
bronchodilator
administration or
annual decline in
FEV1%.
Conclusion:
Our results do not
confi rm the
hypothesis that
airway remodeling in
asthma might be
related to enhanced
ability of
leukocytes to
produce cysteinyl
leukotrienes in
response to various
stimuli.
Key Words:
Asthma. Remodeling.
Leukotrienes. |