BACKGROUND: Allergenic materials from Alternaria are significant causes of human disease. One 31-kD glycoprotein, designated Alt a1, has been described previously as being a significant allergen. OBJECTIVES: The purpose of this study is to characterize purified Alt a1 and to provide a method for measuring it in laboratory and environmental samples. METHODS: Monoclonal antibodies directed to the purified allergen were produced and used to construct a double monoclonal assay for Alt a1. The purified allergen detected by this assay was tested for IgE binding in vitro and in vivo. RESULTS: Purified allergen detected by this assay was shown to bind IgE from patients sensitive to Alternaria and gave a positive skin test in 15 of 16 patients skin test reactive to commercial Alternaria extracts. The assay is sensitive to Alt a1 concentrations as low as 0.2 microg/nmL and is very specific for the allergen. The three commercial Alternaria extracts assayed contained measurable quantities of the allergen varying from 12 to 84 microg/mL. CONCLUSIONS: Alt a1 is a significant Alternaria allergen. The ability to measure this allergen may assist in standardizing Alternaria extracts and lead to an understanding of the significance of exposure to this allergen.
BACKGROUND: Allergenic materials from Alternaria are significant causes of human disease. One 31-kD glycoprotein, designated Alt a1, has been described previously as being a significant allergen. OBJECTIVES: The purpose of this study is to characterize purified Alt a1 and to provide a method for measuring it in laboratory and environmental samples. METHODS: Monoclonal antibodies directed to the purified allergen were produced and used to construct a double monoclonal assay for Alt a1. The purified allergen detected by this assay was tested for IgE binding in vitro and in vivo. RESULTS: Purified allergen detected by this assay was shown to bind IgE from patients sensitive to Alternaria and gave a positive skin test in 15 of 16 patients skin test reactive to commercial Alternaria extracts. The assay is sensitive to Alt a1 concentrations as low as 0.2 microg/nmL and is very specific for the allergen. The three commercial Alternaria extracts assayed contained measurable quantities of the allergen varying from 12 to 84 microg/mL. CONCLUSIONS: Alt a1 is a significant Alternaria allergen. The ability to measure this allergen may assist in standardizing Alternaria extracts and lead to an understanding of the significance of exposure to this allergen.
Authors: Charles Barnes; Jay Portnoy; Michelle Sever; Samuel Arbes; Ben Vaughn; Darryl C Zeldin Journal: Ann Allergy Asthma Immunol Date: 2006-09 Impact factor: 6.347