Asthma is characterized by airway inflammation, bronchial hyperresponsiveness,
and reversible airway obstruction. Medications for asthma include
corticosteroids, β2-adrenergic receptor agonists, chromones, methylxanthines, and
leukotriene modifiers. Despite these advances in therapy, many symptoms are not
well controlled. Since asthma is a chronic airway inflammation with a bias towards
a type 2 T helper (Th2) cell response, some new approaches are targeted towards
the Th2 inflammation pathway. These include anti-IgE therapy, anti-Th2 cytokine
therapy, and therapies aiming at increasing Th1 cytokines. This article will focus on
DNA-based therapy, a novel therapeutic strategy for asthma. Immunostimulatory
gene therapy using CpG oligodeoxynucleotides with central deoxycytidyldeoxyguanosine
(CpG) dinucleotide, in which the cytosine nucleobase is
unmethylated, can stimulate the innate immunity and augment Th1 response. With
DNA gene therapy, genes can be introduced to target Th1 cytokines or other
mediators in the airway in order to counteract Th2 inflammation in asthma. Also,
antisense oligonucleotides can target mRNA species of interest in asthma. Through
these therapies, we can expect long-lasting effects, better control of symptoms, and
reducing medication in the future.
Keywords: Asthma, Th1/Th2, cytokine, CpG, gene therapy, antisense oligonucleotides.
