title: Mixing compatibilities of Aspergillus and American cockroach allergens with other high-protease fungal and insect extracts.
abstract: BACKGROUND
  Recent studies have shown that Alternaria and German cockroach allergens can be degraded by endogenous proteases from other insect and fungal extracts when combined for immunotherapy, but data supporting the compatibilities of other high-protease products in comparable mixtures have not been reported.
  
  
  OBJECTIVE
  To assess the stabilities and compatibilities of Aspergillus fumigatus and American cockroach allergens after mixing with protease-rich extracts from other insects or fungi at concentrations similar to those recommended for subcutaneous immunotherapy.
  
  
  METHODS
  Mixtures containing A fumigatus, American cockroach, and other fungal or insect extracts were evaluated by quantitative (enzyme-linked immunosorbent assays) and qualitative (immunoblotting) methods. Test mixtures and control samples at 10% to 50% glycerin concentrations were analyzed after storage for up to 12 months at 2°C to 8°C.
  
  
  RESULTS
  Moderate to high recoveries of Aspergillus extract activities were retained in control samples and extract mixtures under all conditions examined. American cockroach extract controls were partly degraded at 10% to 25% glycerin, and cockroach allergen compatibilities were decreased significantly in mixtures with several fungal extracts at 25% glycerin. Mixing with other insects did not compromise the stability of American cockroach allergens at 25% to 50% glycerin.
  
  
  CONCLUSIONS
  Aspergillus extracts exhibited favorable stabilities after mixing with other high-protease products. American cockroach extract potencies were unstable in less than 50% glycerin, even in the absence of other protease-containing allergens, and were destabilized in mixtures with several fungal extracts. Addition of fungal and insect extracts to separate treatment vials or preparation of fungal-insect mixtures at elevated glycerin concentrations might be necessary to produce compatible patient formulations for allergen immunotherapy injections.
authors.affiliation: Research and Development Laboratory, Greer Laboratories, Inc, Lenoir, North Carolina. Electronic address: tgrier@greerlabs.com.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Grier
authors.affiliation: Research and Development Laboratory, Greer Laboratories, Inc, Lenoir, North Carolina.
authors.forename: Dawn M
authors.initials: DM
authors.lastname: Hall
authors.affiliation: Research and Development Laboratory, Greer Laboratories, Inc, Lenoir, North Carolina.
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Duncan
authors.affiliation: Research and Development Laboratory, Greer Laboratories, Inc, Lenoir, North Carolina.
authors.forename: Terrance C
authors.initials: TC
authors.lastname: Coyne
mesh_terms: D000485:Allergens / Q000276:immunology*; D000818:Animals; D000946:Antigens, Fungal / Q000276:immunology; D016282:Aspartic Acid Endopeptidases / Q000276:immunology; D001230:Aspergillus / Q000276:immunology*; D002457:Cell Extracts / Q000276:immunology*; D003888:Desensitization, Immunologic; D005656:Fungal Proteins / Q000276:immunology; D006801:Humans; D007073:Immunoglobulin E / Q000276:immunology; D019476:Insect Proteins / Q000276:immunology; D010526:Periplaneta / Q000276:immunology*
chemical_list: C474845:ALTB1 protein, Alternaria brassicicola; D000485:Allergens; D000946:Antigens, Fungal; D002457:Cell Extracts; D005656:Fungal Proteins; D019476:Insect Proteins; C105482:allergen Bla g 1; D007073:Immunoglobulin E; D016282:Aspartic Acid Endopeptidases; C094699:allergen Bla g 2