Identification and possible functions of ADAM33 as an asthma susceptibility gene

Antisense- and RNA interference-based therapeutic strategies in allergy

Modern therapeutic methods for manipulation of gene expression in allergic diseases have been receiving increased attention in the emerging era of functional genomics. With the growing application of gene silencing technologies, pharmacological modulation of translation represents a great advance in molecular therapy for allergy. Several strategies for sequence-specific post-transcriptional inhibition of gene expression can be distinguished: antisense oligonucleotides (AS-ONs), ribozymes (RZs), DNA enzymes (DNAzymes), and RNA interference (RNAi) triggered by small interfering RNAs (siRNAs). Potential anti-mRNA drugs in asthma and other allergic disorders may be targeted to cell surface receptors (adenosine A1 receptor, high-affinity receptor Fc-epsilon RI-alpha, cytokine receptors), adhesion molecules and ligands (ICAM-1, VLA-4), ion channels (calcium-dependent chloride channel-1), cytokines and related factors (IL-4, IL-5, IL-13, SCF, TNF-alpha, TGF-beta1), intracellular signal transduction molecules, such as tyrosine-protein kinases (Syk, Lyn, Btk), serine/ threonine-protein kinases (p38 alpha MAPkinase, Raf-1), non-kinase signaling proteins (RasGRP4), and transcription factors involved in Th2 differentiation and allergic inflammation (STAT-6, GATA-3, NF-kappaB). The challenge to scientists is to determine which of the candidate targets warrants investment of time and resources. New-generation respirable AS-ONs, external guide sequence ribozymes, and RNA interference-based therapies have the potential to satisfy unmet needs in allergy treatment, acting at a more proximal level to a key etiopathogenetic molecular process, represented by abnormal expression of genes. Moreover, antisense and siRNA technologies imply a more rational design of new drugs for allergy.

Genetics of allergic disease

Currently, more than 20.3 million Americans report having asthma and an even greater number suffer from allergies. The cost for treatment of these dis-eases in the United States is greater than $8 billion with more than 40% of this total representing drug expenditure [59]. An intense effort has been made to understand the genetic components of asthma and allergies and how the identified genetic differences influence disease progression and response to drugs. In the future, it will be possible in the clinical setting to analyze a patient's genetic repertoire. From this information, the physician will gain in-sight into the genes involved in producing that subject's allergic and asthmatic phenotype; understand the natural history of that patient's disease;and predict responses (positive and negative) to pharmacologic agents. The end result will be the ability to tailor a specific treatment regime for each patient and reduce the overall cost of health care related to allergies and asthma.