TY - JOUR
T1 - The relationships among immunoglobulin levels, allergic sensitization, and viral respiratory illnesses in early childhood
AU - Possin, Michael E.
AU - Morgan, Stephanie
AU - Dasilva, Douglas F.
AU - Tisler, Christopher
AU - Pappas, Tressa E.
AU - Roberg, Kathy A.
AU - Anderson, Elizabeth
AU - Evans, Michael D.
AU - Gangnon, Ronald
AU - Lemanske, Robert F.
AU - Gern, James E.
PY - 2010/9
Y1 - 2010/9
N2 - IgE plays an essential role in type I allergy, however, there is less information about the relationship between other immunoglobulins (IgA and IgG) and atopic phenotypes in early childhood. We hypothesized that levels of circulating IgA in early childhood would be inversely related to the number of respiratory infections and the risk of becoming sensitized to allergens. Immunoglobulin levels were analyzed (ELISA) in plasma samples (IgG, IgA), and in nasal secretions (IgA) from children participating in a high-risk birth cohort study. Samples were available from 264 children at age 2 yr and 257 children at age 4 yr, and results were compared to rates of respiratory illnesses, allergic sensitization, atopic dermatitis (AD), and asthma. Children who were sensitized to allergens had higher rather than lower levels of circulating IgA. A subgroup analysis showed that IgA levels were increased in relationship to foods sensitization (58 vs. 50 mgdl, p = 0.003) but not aeroallergen sensitization (52 vs. 53 mgdl, p = 0.11). IgA levels in the plasma correlated with levels of IgE levels (rs =0.19, p = 0.003). Levels of IgE, but not IgG or IgA, were positively correlated with rates of respiratory illnesses, AD, and the risk of developing asthma. Finally, there were no significant relationships between IgA in nasal secretions and infectious outcomes. In conclusion, low-normal concentrations of plasma IgA are associated with a reduced prevalence of allergic sensitization in infancy. Further, levels of IgA and IgG in plasma within the range of normal, and IgA in nasal secretions, do not appear to influence the risk of subsequent respiratory illnesses. Further studies to define relationships between IgA and allergic sensitization are likely to provide new insights into the pathogenesis of allergic diseases in infancy.
AB - IgE plays an essential role in type I allergy, however, there is less information about the relationship between other immunoglobulins (IgA and IgG) and atopic phenotypes in early childhood. We hypothesized that levels of circulating IgA in early childhood would be inversely related to the number of respiratory infections and the risk of becoming sensitized to allergens. Immunoglobulin levels were analyzed (ELISA) in plasma samples (IgG, IgA), and in nasal secretions (IgA) from children participating in a high-risk birth cohort study. Samples were available from 264 children at age 2 yr and 257 children at age 4 yr, and results were compared to rates of respiratory illnesses, allergic sensitization, atopic dermatitis (AD), and asthma. Children who were sensitized to allergens had higher rather than lower levels of circulating IgA. A subgroup analysis showed that IgA levels were increased in relationship to foods sensitization (58 vs. 50 mgdl, p = 0.003) but not aeroallergen sensitization (52 vs. 53 mgdl, p = 0.11). IgA levels in the plasma correlated with levels of IgE levels (rs =0.19, p = 0.003). Levels of IgE, but not IgG or IgA, were positively correlated with rates of respiratory illnesses, AD, and the risk of developing asthma. Finally, there were no significant relationships between IgA in nasal secretions and infectious outcomes. In conclusion, low-normal concentrations of plasma IgA are associated with a reduced prevalence of allergic sensitization in infancy. Further, levels of IgA and IgG in plasma within the range of normal, and IgA in nasal secretions, do not appear to influence the risk of subsequent respiratory illnesses. Further studies to define relationships between IgA and allergic sensitization are likely to provide new insights into the pathogenesis of allergic diseases in infancy.
KW - IgA
KW - IgE
KW - allergy
KW - infants
KW - respiratory illnesses
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U2 - 10.1111/j.1399-3038.2010.01041.x
DO - 10.1111/j.1399-3038.2010.01041.x
M3 - Article
C2 - 20444149
AN - SCOPUS:77955788228
SN - 0905-6157
VL - 21
SP - 990
EP - 996
JO - Pediatric Allergy and Immunology
JF - Pediatric Allergy and Immunology
IS - 6
ER -