Specific IgE and IgG antibody-binding patterns to recombinant cockroach allergens.
BACKGROUND
The specificity of serum antibody responses to different cockroach allergens has not been studied.


OBJECTIVE
We sought to quantitate serum IgE and IgG antibodies to a panel of purified cockroach allergens among cockroach-sensitized subjects.


METHODS
IgE antibodies to recombinant cockroach allergens (rBla g 1, rBla g 2, rBla g 4, rBla g 5, and rPer a 7) were measured in sera containing IgE antibodies to Blattella germanica extract (n = 118) by using a streptavidin CAP assay and a multiplex flow cytometric assay. Specific IgG antibodies were determined by using radioimmunoprecipitation techniques.


RESULTS
Specific IgE antibodies measured by means of CAP assay and multiplex assay were strongly correlated ( r = 0.8, P < .001). The sum of IgE antibodies (in international units per milliliter) against all 5 allergens equated to IgE antibodies to cockroach extract. Although the prevalence of IgE antibodies was highest for rBla g 2 (54.4%) and rBla g 5 (37.4%), patterns of IgE antibody binding were unique to each subject. Surprisingly, only 16% of cockroach-sensitized subjects with IgE antibodies to house dust mite exhibited IgE antibody binding to cockroach tropomyosin (rPer a 7). Specific IgE antibodies were associated with increased IgG antibody levels, although detection of IgG in the absence of IgE was not uncommon.


CONCLUSIONS
The techniques described offer a new approach for defining the hierarchy of purified allergens. IgE antibodies directed against 5 allergens constitute the majority of the IgE antibody repertoire for cockroach. Such distinct patterns of IgE-IgG responsiveness to different cockroach allergens highlight the complexity of B-cell responses to environmental allergens.
Satinover
Shama M
SM
Asthma and Allergic Diseases Center, University of Virginia Health System, Charlottesville, VA 22908-1355, USA.
Reefer
Amanda J
AJ
Pomes
Anna
A
Chapman
Martin D
MD
Platts-Mills
Thomas A E
TA
Woodfolk
Judith A
JA
D000293:Adolescent; D000328:Adult; D000485:Allergens / Q000276:immunology; D000595:Amino Acid Sequence; D000818:Animals; D000918:Antibody Specificity; D002648:Child; D002675:Child, Preschool; D003058:Cockroaches / Q000276:immunology*; D003429:Cross Reactions; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D007073:Immunoglobulin E / Q000097:blood / Q000276:immunology*; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology*; D019476:Insect Proteins / Q000276:immunology*; D008875:Middle Aged; D011994:Recombinant Proteins / Q000276:immunology; D017386:Sequence Homology, Amino Acid; D014335:Tropomyosin / Q000276:immunology
D000485:Allergens; D007074:Immunoglobulin G; D019476:Insect Proteins; D011994:Recombinant Proteins; D014335:Tropomyosin; D007073:Immunoglobulin E