In this project we will study the capacity for single nucleotide polymorphisms (SNP) in TLR4
gene to induce varying levels of inflammatory chemokine and cytokine production.
Infection with RSV is the most common cause of respiratory tract illnesses (LRIs) in the
first 3 years of life. There are significant social and health care costs associated with
RSV-LRIs. More than 3% of US children are hospitalized each year due to RSV and 500 die
annually. Several longitudinal studies have also suggested that children who have RSV-LRIs
are at substantially increased risk of developing asthma in the first 3 years after
infection and bronchial hyperresponsiveness (BHR) many years after the primary infection.
Mechanisms involved in RSV disease are not well understood. Recent reports suggest that RSV
may initiate the innate immune response through the pattern recognition receptor, Toll like
receptor-4 (TLR4). In this project we will study the capacity for single nucleotide
polymorphisms (SNP) in TLR4 gene to induce varying levels of inflammatory chemokine and
cytokine production. It has been suggested that such a mechanism may result in altered
immune responses to RSV infection and different clinical outcomes. This research has direct
application to improving our understanding of bronchiolitis in early childhood, particularly
those factors that influence severity of the disease, and may have implications for possible
therapy of patients with bronchiolitis in the future.
1. Parental or sibling history of asthma.
2. Child must be less than 24 months of age.
3. Presence of viral upper or lower respiratory tract symptoms.
1. History of recurrent wheezing requiring systemic corticosteroids.
2. Prior history of lung disease.
3. Birth < 36 weeks gestation.
5. Treatment with ribavirin, systemic or inhaled corticosteroids during the RSV
6. Congenital heart disease.
7. No history of parental or sibling asthma.
8. Less than 48 hour or more than 5 day duration of viral URI symptoms since the peak
symptoms from RSV would be expected to occur from 2-5 days into course of infection.