Comparison of rhinovirus antibody titers in children with asthma exacerbations and species-specific rhinovirus infection.
BACKGROUND
Asthma exacerbations are associated with human rhinovirus (HRV) infections, and more severe exacerbations are associated with HRV-C. We have previously shown that the HRV-C-specific antibody response is low in healthy adult sera and that most of the antibody to HRV-C is cross-reactive with HRV-A.


OBJECTIVE
To compare the antibody response to each HRV species in asthmatic and nonasthmatic children in whom the type of HRV infection was known.


METHODS
Total and specific IgG₁ binding to HRV viral capsid protein antigens of HRV-A, -B, and -C were tested in the plasma from nonasthmatic children (n = 47) and children presenting to the emergency department with asthma exacerbations (n = 96). HRV, found in most of the children at the time of their exacerbation (72%), was analyzed using molecular typing.


RESULTS
Asthmatic children had higher antibody responses to HRV. The titers specific to HRV-A, and to a lesser extent HRV-B, were higher than in nonasthmatic controls. The species-specific responses to HRV-C were markedly lower than titers to HRV-A and HRV-B in both asthmatic and nonasthmatic children (P < .001). The titers both at presentation and after convalescence were not associated with the HRV genotype detected during the exacerbation.


CONCLUSIONS
The higher total anti-HRV antibody titers of asthmatic children and their higher anti-HRV-A and -B titers show their development of a heightened antiviral immune response. The low species-specific HRV-C titers found in all groups, even when the virus was found, point to a different and possibly less efficacious immune response to this species.
Telethon Institute for Child Health Research, University of Western Australia, Perth, Australia.
Jua
J
Iwasaki
Telethon Institute for Child Health Research, University of Western Australia, Perth, Australia.
Wendy-Anne
WA
Smith
School of Paediatrics and Child Health, University of Western Australia, Perth, Australia.
Siew-Kim
SK
Khoo
School of Paediatrics and Child Health, University of Western Australia, Perth, Australia.
Joelene
J
Bizzintino
School of Paediatrics and Child Health, University of Western Australia, Perth, Australia; School of Public Health, Curtin University, Perth, Australia.
Guicheng
G
Zhang
School of Paediatrics and Child Health, University of Western Australia, Perth, Australia.
Des W
DW
Cox
School of Paediatrics and Child Health, University of Western Australia, Perth, Australia.
Ingrid A
IA
Laing
School of Paediatrics and Child Health, University of Western Australia, Perth, Australia.
Peter N
PN
Le Souëf
Telethon Institute for Child Health Research, University of Western Australia, Perth, Australia.
Wayne R
WR
Thomas
Telethon Institute for Child Health Research, University of Western Australia, Perth, Australia; School of Paediatrics and Child Health, University of Western Australia, Perth, Australia. Electronic address: belinda@ichr.uwa.edu.au.
Belinda J
BJ
Hales
D000293:Adolescent; D000914:Antibodies, Viral / Q000097:blood*; D001249:Asthma / Q000150:complications / Q000276:immunology* / Q000473:pathology / Q000821:virology; D036022:Capsid Proteins / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D003429:Cross Reactions; D005260:Female; D006801:Humans; D056724:Immunity, Humoral; D007074:Immunoglobulin G / Q000097:blood*; D007223:Infant; D008297:Male; D010850:Picornaviridae Infections / Q000150:complications / Q000276:immunology* / Q000473:pathology / Q000821:virology; D011485:Protein Binding; D012229:Rhinovirus / Q000145:classification / Q000276:immunology*; D012720:Severity of Illness Index; D013045:Species Specificity
D000914:Antibodies, Viral; D036022:Capsid Proteins; D007074:Immunoglobulin G
Human rhinovirus; IgG(1) antibody; VP1; asthma exacerbation; children