Terrelysin, a potential biomarker of exposure to Aspergillus terreus.
Nayak-AP; Green-BJ; Beezhold-DH
J Allergy Clin Immunol 2012 Feb; 129(2)(Suppl):AB81
RATIONALE: Exposure to airborne fungi has been associated with a variety of adverse health effects ranging from allergies and asthma, to opportunistic infections. However, not all species are equally problematic and improved diagnostics are essential to develop exposure and surveillance information. Here, we describe the development of monoclonal antibodies (mAbs) to a hemolysin (terrelysin) using Aspergillus terreus as a model species for development of a specific biomarker of exposure. METHODS: Sixteen murine IgG mAbs were developed after immunization of mice with recombinant terrelysin and tested for reactivity in ELISA (screening) and Western blot assays (cross-reactivity). Epitopes for 3 of the mAbs were determined using synthetic peptides immobilized onto cellulose supports. Microscopic methods were used to monitor fungal growth and immunohistochemistry methods were utilized to study immunolocalization of terrelysin. RESULTS: mAbs showed reactivity towards multiple strains of Aspergillus terreus and cross-reactivity analysis identified 3 mAbs to be species-specific. Furthermore, epitope analysis showed that 2 mAbs of different isotypes recognize the same epitope while the other mAb recognizes a different epitope. Immunolocalization studies demonstrated that terrelysin is localized more abundantly at hyphal tips. Time course studies showed that unlike fungal proteolytic enzymes, terrelysin was expressed during early hyphal growth but reduced after mycelial expansion. Terrelysin was also detected early during growth in the culture supernatant, suggesting secretion. CONCLUSIONS: Our goal is to better understand the adverse health effects caused by fungal exposures. The species-specific mAbs will be useful tools in determining the potential of terrelysin as a potential biomarker for Aspergillus terreus exposure.
Exposure-levels; Exposure-limits; Fungi; Airborne-particles; Allergies; Breathing; Respiration; Respiratory-infections; Respiratory-irritants; Respiratory-system-disorders; Pulmonary-function; Pulmonary-system-disorders; Biomarkers; Laboratory-animals; Monitors
Healthcare and Social Assistance; Services
Journal of Allergy and Clinical Immunology