Serum and Salivary IgE, IgA, and IgG4 Antibodies to Dermatophagoides pteronyssinus and Its Major Allergens, Der p1 and Der p2, in Allergic and Nonallergic Children

Allergic rhinitis (AR) is a public health problem with high prevalence worldwide. We evaluated levels of specific IgE, IgA, and IgG4 antibodies to the Dermatophagoides pteronyssinus (Dpt) house dust mite and to its major allergens (Der p1 and Der p2) in serum and saliva samples from allergic and nonallergic children. A total of 86 children were analyzed, from which 72 had AR and 14 were nonallergic healthy children. Serum IgE and serum/salivary IgG4 levels to Dpt, Der p1, and Der p2 were higher in allergic children whereas serum/salivary IgA levels to all allergens were higher in nonallergic children. IgE levels positively correlated with IgG4 and IgA to all allergens in allergic children, while IgA levels negatively correlated with IgG4 to Dpt and Der p1 in nonallergic children. In conclusion, mite-specific IgA antibodies predominate in the serum and saliva of nonallergic children whereas mite-specific IgE and IgG4 are prevalent in allergic children. The presence of specific IgA appears to have a key role for the healthy immune response to mucosal allergens. Also, specific IgA measurements in serum and/or saliva may be useful for monitoring activation of tolerance-inducing mechanisms during allergen specific immunotherapeutic procedures, especially sublingual immunotherapy

Serum and Salivary IgE, IgA, and IgG 4 Antibodies to Dermatophagoides pteronyssinus and Its Major Allergens, Der p1 and Der p2, in Allergic and Nonallergic Children

Allergic rhinitis (AR) is a public health problem with high prevalence worldwide. We evaluated levels of specific IgE, IgA, and IgG4 antibodies to the Dermatophagoides pteronyssinus (Dpt) house dust mite and to its major allergens (Der p1 and Der p2) in serum and saliva samples from allergic and nonallergic children. A total of 86 children were analyzed, from which 72 had AR and 14 were nonallergic healthy children. Serum IgE and serum/salivary IgG4 levels to Dpt, Der p1, and Der p2 were higher in allergic children whereas serum/salivary IgA levels to all allergens were higher in nonallergic children. IgE levels positively correlated with IgG4 and IgA to all allergens in allergic children, while IgA levels negatively correlated with IgG4 to Dpt and Der p1 in nonallergic children. In conclusion, mite-specific IgA antibodies predominate in the serum and saliva of nonallergic children whereas mite-specific IgE and IgG4 are prevalent in allergic children. The presence of specific IgA appears to have a key role for the healthy immune response to mucosal allergens. Also, specific IgA measurements in serum and/or saliva may be useful for monitoring activation of tolerance-inducing mechanisms during allergen specific immunotherapeutic procedures, especially sublingual immunotherapy

Early Exposure to Respiratory Allergens by Placental Transfer and Breastfeeding.

The relationship between allergen exposure and the onset of or protection from allergic diseases remains unclear. Many factors could be related to immunological responses, such as the age when the exposure occurs, type of allergen, timing, dose, and allergen route. In this study, we investigated whether exposure to respiratory allergens could occur in pregnancy or early life. In particular, we assessed whether Der p 1 and Blo t 5, as well as specific antibodies against these allergens, could be detected in 90 paired cord blood and colostrum samples. Der p 1 was detected in 58.6% of colostrum and 29% of cord blood samples, whereas Blot 5 was positive in 41.3% and 9.6% of the samples, respectively. Similar to specific IgA, which could be detected in all samples for both mites, specific IgG was found in a high number of colostrum samples, 93.5% and 94.8% for Dp and Bt, respectively. Although allergens were not detected in all cord blood samples, a high percentage of them (≥95%) were positive for specific IgM to both mites in cord blood samples, suggesting that neonates can be exposed and sensitized to airborne allergens during pregnancy. Many studies have attempted to correlate allergen exposure or its prevention in early infancy with the onset of or protection from allergic diseases. However, conflicting and inconsistent data do not show a clear correlation with or suggest a way to prevent allergen sensitization. Nevertheless, these unconvincing results could be better understood if the relationship with many aspects of allergen exposure after pregnancy could be clarified. Thus, it is necessary to address basic issues related to allergen exposure, including the development of reproducible, standardized and reliable methods, and to determine how and where the exposure occurs

Correlations between Der p 1 and Blo t 5 in colostrum samples.

<p>Correlation coefficients were determined using Spearman’s tests.</p

Specific IgM to <i>B</i>. <i>tropicalis</i> and <i>D</i>. <i>pteronyssinus</i> in cord blood samples.

<p>* For only positive samples. Detection limit, 1 AU/mL.</p><p>Specific IgM to <i>B</i>. <i>tropicalis</i> and <i>D</i>. <i>pteronyssinus</i> in cord blood samples.</p

Levels of Der p 1 and Blo t 5 allergens in the cord blood and colostrum samples.

<p>Horizontal lines represent the median detected allergen levels. All <i>p</i>-values were determined using the Wilcoxon signed rank test; ** <i>p</i> < 0.01; ***<i>p</i> < 0.001. </p

Correlation between specific IgA or IgG to Dp (A) or Bt (B) and Der p 1 (A) or Blo t 5 (B) allergens.

<p>Correlation coefficients were determined using Spearman’s tests; ** <i>p</i> < 0.01.</p

Specific IgG subclasses to <i>B</i>. <i>tropicalis</i> and <i>D</i>. <i>pteronyssinus</i> in maternal serum and cord blood samples.

<p>* For only positive samples. MB, Maternal blood; CB, Cord blood. Detection limit, 1 AU/mL.</p><p>Specific IgG subclasses to <i>B</i>. <i>tropicalis</i> and <i>D</i>. <i>pteronyssinus</i> in maternal serum and cord blood samples.</p

Mother and child data.

<p>* ImmunoCap score (ICS—<b>0</b> <0.35kU/L; <b>1</b> 0.35–0.7kU/L; <b>2</b> 0.7–3.5kU/L; <b>3</b> 3.5–17.5kU/L; <b>4</b> 17.5–50.0kU/L; <b>5</b> 50.0–100.0kU/L; <b>6</b> >100.0kU/L).</p><p>Mother and child data.</p

Antibody and sample dilution for specific IgA, IgG and IgM antibodies against <i>B</i>. <i>tropicalis</i> and <i>D</i>. <i>pteronyssinus</i>, as measured by ELISA assays.

<p>Antibody and sample dilution for specific IgA, IgG and IgM antibodies against <i>B</i>. <i>tropicalis</i> and <i>D</i>. <i>pteronyssinus</i>, as measured by ELISA assays.</p