Genes, Soy Isoflavones, and Virus

Pediatric asthma affects 8.3% of U.S. children, accounting for 5.92 billion dollars of U.S. health care expenditure annually. Approximately 80% of the children who progress to have asthma will have wheeze in early childhood, suggesting that primary prevention should target infancy. In particular, severe early life viral lower respiratory tract infection (LRTI) shows strong associations with asthma development which are modified by genetic predisposition.1-5 A gain of function plasminogen activator inhibitor-1 (PAI-1) promoter variant is present in up to 60% of the population who develop asthma in either homozygote or heterozygote form. If children with ≥1 copy of the PAI-1 risk allele had a respiratory viral illness requiring a physician visit before 2 years old, these subjects had a 12-fold (any virus) to 18-fold (self-reported Respiratory Syncytial Virus (RSV)) increased risk of developing asthma. PAI-1 production increases in the airway at the time of a viral illness and promotes both fibrosis and an allergic airway milieu. We have found that soy isoflavones decrease the production of PAI-1 and decrease rates of asthma exacerbations by 75% in subjects with the risk gene. This pilot will allow for preliminary data to determine if on-demand treatment with soy isoflavone improves epithelial integrity and decreases Th2 airway responses if dosed with onset of illness. This would establish the viability of on demand treatment for early life viral illness which may modulate acute outcomes. In this study, we will assess whether children without established asthma who have the PAI-1 genotype will have higher PAI-1 levels and remodeling / allergic inflammatory pathways in their airways than children who do not have the genotype. We will also determine if soy isoflavones given when presenting for an acute respiratory illness can decrease these changes in children both with and without the genotype. Finally, we will also study these questions in a lung organoid / Air Liquid Interface (ALI) model with cells from subjects with the risk allele, which will allow us to compare soy isoflavone pre-inoculation treatment with treatment post infection in a controlled experiment. These data would be essential to set up the team to assess the effects of on demand treatment of children with LRTI irrespective of asthma after presentation to the ED. This would be an important step forward compared to chronic treatment in high-risk populations which will have barriers to implementation.