A new
macrolide,
roxithromycin, may be an effective treatment for
asthma. Lymphocyte apoptosis is impaired in patients with
asthma, while spontaneous apoptosis increases during remission, and such changes may be involved in the onset and remission of mite-sensitive
asthma. Lymphocyte apoptosis was evaluated by incubating cells from patients with
asthma in the presence of
roxithromycin. Low concentrations of
roxithromycin (1-500 ng/ml) augmented the early, but not late, phase of apoptosis in Dermatophagoides farinae-stimulated peripheral blood mononuclear (
PBM) cells, while high concentrations of
roxithromycin (1 microg/ml; 6 microg/ml is the maximum serum level) augmented both the early and late phases of apoptosis. In both unstimulated and
phytohemagglutinin-stimulated cells,
roxithromycin did not significantly affect the induction of apoptosis. In cells from normal subjects,
roxithromycin did not affect the induction of apoptosis. Other
antibiotics, including
cefazolin and
ampicillin, did not cause significant induction of apoptosis.
Fas ligand, but not
Fas receptor, expression on D. farinae-stimulated cells was up-regulated after stimulation with 1 microg/ml
roxithromycin, while Bcl-2 expression on both unstimulated and D. farinae-stimulated cells showed a decrease after the same treatment.
Roxithromycin can induce apoptosis of D. farinae-activated lymphocytes in patients with D. farinae-sensitive
asthma. Induction of the Fas/
Fas ligand system and reduced Bcl-2 expression were involved in the promotion of apoptosis by
roxithromycin treatment.