Understanding the mechanisms of viral induced asthma: New therapeutic directions

Abstract

Asthma is a common and debilitating disease that has substantially increased in prevalence in Western Societies in the last 2 decades. Respiratory tract infections by respiratory syncytial virus (RSV) and rhinovirus (RV) are widely implicated as common causes of the induction and exacerbation of asthma. These infections in early life are associated with the induction of wheeze that may progress to the development of asthma. Infections may also promote airway inflammation and enhance T helper type 2 lymphocyte (Th2 cell) responses that result in exacerbations of established asthma. The mechanisms of how RSV and RV induce and exacerbate asthma are currently being elucidated by clinical studies, in vitro work with human cells and animal models of disease. This research has led to many potential therapeutic strategies and, although none are yet part of clinical practise, they show much promise for the prevention and treatment of viral disease and subsequent asthma.

Double-Stranded RNA Exacerbates Pulmonary Allergic Reaction through TLR3: Implication of Airway Epithelium and Dendritic Cells

“…Recent reports demonstrated that extracellular delivery of oligonucleotides is efficiently transported toward lysosomal TLR through the mobilization of scavenger receptors (42,43). Moreover, our model mimics the clinical situation associated with virus-induced asthma exacerbation, including an increase of AHR, eosinophilic airway inflammation, innate immune cell infiltrate, allergen-specific Ig levels, development of Th2 cells, and secretion of Th2-associated chemokines (6,21,44). Finally, in mice treated with dsRNA/OVA as well as in animals during respiratory viral infection and during respiratory syncitial virus-enhanced allergic inflammation (45,46), CD8 + T cells represent the majority of T lymphocytes infiltrating lung tissue and draining LNs (Fig.…”

Childhood asthma and infection: virus-induced exacerbations as determinants and modifiers: Figure 1–

“…Allergens and respiratory viruses act synergistically in the expression of asthma symptoms in adults and children [13,33]. RV-induced epithelial cytotoxicity could increase the penetration and effects of allergens, leading to further induction of inflammation [87,88]. Synergy between virus and mite (Dermatophagoides pteronyssinus antigen 1)-induced inflammation may also occur through combined nuclear factor-kB activation [89].…”

Structure-Function Analysis of CCL28 in the Development of Post-viral Asthma

“…It is a complex disease characterized by airway hyper-responsiveness, inflammation, and tissue remodeling resulting in episodic airflow obstruction and clinical symptoms of wheezing, coughing, and shortness of breath (2). Asthma is a major public health issue in the United States as it is the number one illness leading to school absences in children (3), and in 2010 alone asthma accounted for 3404 deaths and 1.8 million emergency department visits (4).…”