Specific IgE and IgG Antibodies to Human Rhinovirus 16 Capsid Protein VP1 Among Asthmatic and Non-Asthmatic Children from Costa Rica: Comparison with Virginia and Northern Sweden
Sunday, March 6, 2016
South Exhibit Hall H (Convention Center)
Thomas A.E. Platts-Mills, MD PhD FAAAAI, Alexander J. Schuyler, BS BA, Lisa J Workman, BA, Eva Rönmark, PhD, Lydiana Avila, Peter W. Heymann, MD
Rationale: Rhinovirus (RV) causes approximately 70-80% of acute asthma exacerbations among children living in temperate and tropical climates. The icosahedral RV capsid is composed of viral proteins (VP) 1-4, and antibodies directed against epitopes on exterior regions of VP1-3 are a major component of the humoral response to infection.  Here we present serum IgE, IgG, and IgG4 levels to RV-16 VP1 in subjects from three countries.

Methods:   Sera collected from asthmatic or non-asthmatic subjects from Costa Rica, Virginia, and northern Sweden were assayed for specific antibodies to RV capsid proteins.  Specific IgE and IgG4 antibodies to RV-16 VP1 were measured by ImmunoCAP using biotinylated antigen coupled to a streptavidin immunosorbent.  Serum IgG antibodies were adsorbed onto recombinant Protein G-Sepharose and incubated with radiolabeled RV-16 VP1 or RV-3 VP2.  The radioactivity of bound antigen was measured using a gamma counter.

Results: IgG antibodies to RV-16 VP1 were higher in titer and prevalence compared to serum levels of IgG to RV-3 VP2 among subjects from Virginia.  Specific IgE and IgG4 antibodies to RV-16 VP1 were detected in low quantities in subjects from Costa Rica and Virginia.  Though not associated with atopy in Virginia or asthma in northern Sweden, asthmatic children from Costa Rica had higher levels of IgG antibodies to RV-16 VP1 compared to controls in that country.  Furthermore, IgG antibodies to RV-16 VP1 were higher in Costa Rican children who were positive for RV-A by PCR compared to those positive to RV-C.

Conclusions: These data suggest the antibody response against RV is dominated by IgG1.