Measurement of IgE and IgG subclass antibodies to whole body antigen and two major allergens (Der fI & Der fII) of Dermatophagoides farinae in normal subjects and asthmatics

Influence of the Adjuvants and Genetic Background on the Asthma Model Using Recombinant Der f 2 in Mice

Der f 2 is the group 2 major allergen of a house dust mite (Dermatophagoides farinae) and its function has been recently suggested. To determine the optimal condition of sensitization to recombinant Der f 2 (rDer f 2) in murine model of asthma, we compared the effectiveness with different adjuvants in BALB/c and C57BL/6 mice. Mice from both strains sensitized with rDer f 2 by intraperitoneal injection or subcutaneous injection on days 1 and 14. The dosage was 20 µg. Freund's adjuvants with pertussis toxin (FP) or alum alone were used as adjuvants. On days 28, 29, and 30, mice were challenged intranasally with 0.1% rDer f 2. We evaluated airway hyperresponsivenss, eosinophil proportion in lung lavage, airway inflammation, and serum allergen specific antibody responses. Naive mice were used as controls. Airway hyperresponsiveness was increased in C57BL/6 with FP, and BALB/c with alum (PC200: 13.5±6.3, 13.2±6.7 vs. >50 mg/ml, p<0.05). The eosinophil proportion was increased in all groups; C57BL/6 with FP, BALB/c with FP, C57BL/6 with alum, BALB/c with alum (24.8±3.6, 20.3±10.3, 11.0±6.9, 5.7±2.8, vs. 0.0±0.0%, p<0.05). The serum allergen specific IgE levels were increased in C57BL/6 with FP or alum (OD: 0.8±1.4, 1.1±0.8, vs. 0.0±0.0). C57BL/6 mice were better responders to rDer f 2 and as for adjuvants, Freund's adjuvant with pertussis toxin was better.

House dust mite allergy in Korea: the most important inhalant allergen in current and future

The house-dust mite (HDM), commonly found in human dwellings, is an important source of inhalant and contact allergens. In this report, the importance of HDM allergy in Korea and the characteristics of allergens from dust mite are reviewed with an emphasis on investigations performed in Korea. In Korea, Dermatophagoides farinae is the dominant species of HDM, followed by D. pteronyssinus. Tyrophagus putrescentiae is also found in Korea, but its role in respiratory allergic disease in Korea is controversial. The relatively low densities of mite populations and concentrations of mite major allergens in dust samples from Korean homes, compared to westernized countries, are thought to reflect not only different climatic conditions, but also cultural differences, such as the use of 'ondol' under-floor heating systems in Korean houses. HDM are found in more than 90% of Korean houses, and the level of exposure to HDM is clinically significant. About 40%-60% of Korean patients suffering from respiratory allergies, and more than 40% of patients suffering from atopic dermatitis, are sensitized to HDM. Mite allergens can be summarized according to their inherent auto-adjuvant activities and/or their binding affinities to the adjuvant-like substances: proteolytic enzymes, lipid binding proteins, chitin binding proteins, and allergens not associated with adjuvant-like activity. In general, allergens with a strong adjuvant-like activity or adjuvant-binding activity elicit potent IgE reactivity. In Korea, Der f 2 is the most potent allergen, followed by Der f 1. Immune responses are modulated by the properties of the allergen itself and by the adjuvant-like substances that are concomitantly administered with the antigens. Characterization of allergenic molecules and elucidation of mechanisms by which adjuvant-like molecules modulate allergic reactions, not only in Korea but also worldwide, will provide valuable information on allergic diseases, and are necessary for the development of diagnostic tools and therapeutic strategies.

[The levels of IgG subclasses in respiratory allergic pathology in the childhood]

OBJECTIVES

To assess the existence of immunologic alterations, referring to IgG subclasses, in the respiratory allergic pathology in the childhood.

MATERIAL AND METHODS

This is a prospective study that compares the IgG subclasses levels in a sample of patient with allergic breathing illness (n = 169) and a group control (n = 130) with ages range from one month to 13 years old. The statistical analysis includes a descriptive statistic and a comparative statistic carrying out comparison of means between both groups with the Welch test and the Student's T test.

RESULTS

The mean rate of IgG1 in the group with breathing allergic pathology being of 578,1 mg/dl and in the control group, being of 632,78 mg/dl. The mean rate of IgG2 in the group with breathing allergic pathology being of 106,12 mg/dl and in the control group, being of 142,38 mg/dl. The mean rate of IgG3 in the group with breathing allergic pathology being of 53,73 mg/dl and in the control group, being of 63,78 mg/dl. The children with breathing allergic pathology have significantly decreased IgG1, IgG2, IgG3 levels in comparison to the control group (p < 0.001). The mean rate of IgG4 in the group with breathing allergic pathology being of 25,86 mg/dl and in the control group, being of 13,89 mg/dl. The children with breathing allergic pathology have significantly elevated IgG4 levels in comparison to the control group (p < 0.001).

CONCLUSIONS

The findings obtained suggest that an relation exists in the breathing allergic processes with the IgG subclasses levels disturbances and also that there is an alteration of the immune response maturation in relation to subclasses IgG1, IgG2, IgG3. The valuation of the levels of these immunoglobulins can be useful in the pathogenic diagnosis of the allergic processes.

Seasonal variation of IgG subclass antibodies to house dust mite in sera from mite-sensitive asthmatic patients

BACKGROUND

House dust mite is an important cause of bronchial asthma. Seasonal variation of environmental house dust mite allergen levels and the specific IgE antibody to house dust mite have been reported.

OBJECTIVE

We studied the changes in IgG subclass antibodies to house dust mite associated with seasonal variation of house dust mite allergen levels in houses of mite-sensitive asthmatic patients.

METHODS

In 14 mite-sensitive asthmatic patients, house dust mite allergen (Der f 1) contents in bedding were measured monthly, and IgG subclass antibodies to house dust mite, Dermatophagoides farinae (D. farinae), were determined by enzyme-linked immunosorbent assay (ELISA) every 3 months from July to December.

RESULTS

The concentration of Der f 1 in dust from bedding reached maximum levels in August and September, and significantly decreased in November and December compared with August and September (P < .05). Levels of D. farinae-specific IgG4 antibodies significantly decreased in December compared with September (P < .05) with no statistically significant change between September and June (P > .05). Levels of D. farinae-specific IgG2 antibodies decreased significantly in December compared with June (P < .05). The levels of IgG1 and IgG3 antibodies to D. farinae showed no significant differences during the study period.

CONCLUSION

These findings suggest that seasonal changes in natural exposure to house dust mite allergen might lead to concurrent changes in specific IgG4 antibodies to house dust mite in mite-sensitive asthmatic patients and each IgG subclass antibodies to house dust mite might have a different kinetics.