Serum and Salivary IgE, IgA, andIgG4Antibodies toDermatophagoides pteronyssinusand Its Major Allergens, Der p1 and Der p2, in Allergic and Nonallergic Children

Abstract

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.

Allergen-Specific IgG Antibodies Purified from Mite-Allergic Patients Sera Block the IgE Recognition ofDermatophagoides pteronyssinusAntigens: AnIn VitroStudy

“…A previous study in patients of the Triângulo Mineiro region, Brazil [21], showed high positivity percentages to HDM extracts, underlining D. pteronyssinus and D. farinae as relevant sensitizing agents in this region. IgE levels and seropositivity in atopic patients found in this study resembled those found in our previous work evaluating the levels of IgE, IgA, and IgG4 antibodies to D. pteronyssinus and to its major allergens, Der p1 and Der p2, in samples of serum and saliva from allergic and nonallergic children [14]. Although the mean levels of IgG4 to Dpt were higher in atopic than in nonatopic subjects of the present study, this difference was not statistically significant as that found in our previous studies with D. pteronyssinus [14] and Blomia tropicalis [22], reinforcing that antigens that induce IgE antibodies are also good inducers of IgG4 antibodies.…”

“…IgE levels and seropositivity in atopic patients found in this study resembled those found in our previous work evaluating the levels of IgE, IgA, and IgG4 antibodies to D. pteronyssinus and to its major allergens, Der p1 and Der p2, in samples of serum and saliva from allergic and nonallergic children [14]. Although the mean levels of IgG4 to Dpt were higher in atopic than in nonatopic subjects of the present study, this difference was not statistically significant as that found in our previous studies with D. pteronyssinus [14] and Blomia tropicalis [22], reinforcing that antigens that induce IgE antibodies are also good inducers of IgG4 antibodies. These findings were supported by significant positive correlation found between Dpt-specific IgE and IgG4 antibodies in atopic patients.…”

“…All serum samples were assessed by enzyme linked immunosorbent assay (ELISA) for measuring levels of IgE, IgG1, and IgG4 to Dpt as previously described [14, 15], with some modifications. Briefly, microtiter plates were coated with Dpt extract (2  μ g/well; Hollister-Stier Laboratories, Spokane, WA, USA), blocked with phosphate-buffered saline (PBS, pH 7.2) containing 0.05% Tween 20 and 1% bovine serum albumin (PBS-T-BSA) for IgE and PBS-T-BSA 0.1% for IgG1 and IgG4, and then incubated with serum samples diluted 1 : 2 (IgE), 1 : 10 (IgG1), or 1 : 5 (IgG4) for 2 hours at 37°C.…”

“…An indirect ELISA was carried out to determine the optimal concentrations of specific and nonspecific IgG fractions through detection of IgG1 and IgG4 anti-Dpt as well as residual specific IgE as previously described [14, 15], with modifications. Briefly, plates were coated with Dpt (2  μ g/well), blocked with PBS-T-BSA 0.1%, and subsequently incubated with specific and nonspecific IgG fractions diluted from 40 to 2.5  μ g/well.…”

Specific Antibodies in Oral Immunotherapy for Cow's Milk Allergy: Kinetics and Prediction of Clinical Outcome

“…In a study that compared children with allergic rhinitis and house dust mite sensitization to nonatopic children, low specific IgA levels in serum and saliva were associated with allergy [22]. Studies on grass pollen immunotherapy imply a role for specific IgA [23] and IgA2 [24] in the development of tolerance, since these serum levels increased as allergic symptoms improved.…”