Abstract
Background House dust mites are important allergen sources and some of these allergenic proteins may contain carbohydrate moieties, which are able to be isolated using lectins, as Concanavalin A (ConA). This study aimed to investigate allergenicity (IgE) and antigenicity (IgG1 and IgG4) of ConA-unbound and ConA-bound Dermatophagoides pteronyssinus (Dpt) crude extracts using sera of mite-allergic patients as well as inhibition capacity of antibody binding. Material and Methods We obtained mannose-enriched and mannose-depleted fractions from Dpt by ConA affinity chromatography. Both ConA-bound and ConA-unbound fractions were evaluated by ELISA and Western Blotting for specific IgE, IgG1, and IgG4 reactivity with sera obtained from 95 mite-allergic patients (DP+) and 92 nonallergic (NA) subjects. Inhibition ELISA was used to assess cross-reactivity between Dpt extract and its fractions. Results Among the DP+ patients, no difference was found between ConA-unbound and ConA-bound fractions regarding the levels of specific IgE, IgG1, and IgG4. Nonallergic subjects had the same levels of specific IgG1 to both ConA-unbound and ConA-bound fractions, although for specific IgG4, values were higher for ConA-bound. A positive correlation was found among specific IgE, IgG1, and IgG4 levels when Dpt was compared to ConA-unbound and ConA-bound fractions. Recognition of crude Dpt by IgE, IgG1, and IgG4 was highly inhibited by ConA-unbound and ConA-bound fractions. Western Blotting revealed a broad spectrum of bands ranging from 14 to 116 kDa recognized by specific IgE and IgG4. However, IgG1 reached higher frequency values on high molecular weight polypeptides. Conclusion ConA-unbound and ConA-bound fractions derived from D. pteronyssinus crude extract revealed important components involved in the IgE recognition in allergic patients as well as IgG1 and/or IgG4 in allergic and healthy subjects.
Highlights
House dust mites (HDM) have been described as important allergen sources causing respiratory allergies, such as asthma and rhinitis, and this association has led to the realization of several studies aiming to elucidate the role of the exposure to these allergens on the synthesis of components of the immune system, including cytokines, such as IL-4, IL-5, and IL-13 as well as different immunoglobulin classes [1]
BioMed Research International is a glycosylated protein with cysteine-protease function that exhibits high identity to Der f 1, from D. farinae, and it is involved in the barrier disruption and Th2 cell differentiation [9] while Der p 2 is likely associated with Tolllike receptors, TLR-4, by triggering components in the innate immunity [10]
Concanavalin A (ConA)-bound fraction presented the lowest amount of total protein and carbohydrate (500 μg/ml and 200 μg/ml, respectively) and the highest protein/carbohydrate ratio (2.5), indicating that carbohydrate levels in relation to protein levels are lower in this fraction, comparing to ConA-unbound either Dermatophagoides pteronyssinus (Dpt) extract
Summary
House dust mites (HDM) have been described as important allergen sources causing respiratory allergies, such as asthma and rhinitis, and this association has led to the realization of several studies aiming to elucidate the role of the exposure to these allergens on the synthesis of components of the immune system, including cytokines, such as IL-4, IL-5, and IL-13 as well as different immunoglobulin classes [1]. This study aimed to investigate allergenicity (IgE) and antigenicity (IgG1 and IgG4) of ConA-unbound and ConA-bound Dermatophagoides pteronyssinus (Dpt) crude extracts using sera of mite-allergic patients as well as inhibition capacity of antibody binding. We obtained mannoseenriched and mannose-depleted fractions from Dpt by ConA affinity chromatography Both ConA-bound and ConA-unbound fractions were evaluated by ELISA and Western Blotting for specific IgE, IgG1, and IgG4 reactivity with sera obtained from 95 mite-allergic patients (DP+) and 92 nonallergic (NA) subjects. ConA-unbound and ConA-bound fractions derived from D. pteronyssinus crude extract revealed important components involved in the IgE recognition in allergic patients as well as IgG1 and/or IgG4 in allergic and healthy subjects
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
