Immunobiochemical analysis of cross-reactive glutathione-S-transferase allergen from different fungal sources.
Clinical observations suggest the presence of cross-reactive allergens. There is a need to identify these cross-reactive allergens to improve the treatment used for allergic disorders. The present study was aimed to identify and characterize a cross-reactive allergenic protein from fungi. Allergen extracts of various fungi viz. Alternaria alternata, Aspergillus fumigatus, Cladosporium herbarum, Curvularia lunata, and Epicoccum purpurascens showed GST enzymatic activity ranging from 0.765 to 1.004 delta340 nm/min/microg where as activity of rGST was 1.123 delta340 nm/min/microg. Immunoblot with GST antibodies showed a band of approximately 26 kDa in all these fungal extracts. Sera of fungal allergy patients showed the presence of IgE antibodies to GST. Rabbit antibodies raised against the fungal extracts reacted with rGST confirming the presence of GST-like protein in these extract. ELISA inhibition using GST antibodies revealed inhibition with C. herbarum, A. alternata, C. lunata, A. fumigatus, and E. purpurascens demonstrating that fungal GST competes for binding to anti-GST. In summary, a GST-like protein was recognized as cross-reactive allergen in these fungal extracts.
Shankar
Jay
J
Allergy and Immunology Section, Institute of Genomics and Integrative Biology, Delhi University Campus, Delhi, India.
Gupta
Paromita D
PD
Sridhara
Susheela
S
Singh
B P
BP
Gaur
S N
SN
Arora
Naveen
N
D000328:Adult; D000485:Allergens / Q000276:immunology*; D000818:Animals; D015153:Blotting, Western; D003429:Cross Reactions / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes / Q000276:immunology; D005658:Fungi / Q000201:enzymology / Q000276:immunology*; D005982:Glutathione Transferase / Q000276:immunology*; D006801:Humans; D006967:Hypersensitivity / Q000276:immunology*; D007073:Immunoglobulin E / Q000276:immunology*; D008875:Middle Aged; D011817:Rabbits
D000485:Allergens; D000939:Epitopes; D007073:Immunoglobulin E; D005982:Glutathione Transferase