Allergic potency of recombinant Fel d 1 is reduced by low concentrations of chlorine bleach.
BACKGROUND
Sodium hypochlorite (NaOCl), the primary component of household bleach, has been shown to alter the purified mouse allergen Mus m 1, such that antibody recognition, or immunogenicity, is lost. Results of initial experiments suggest that antibody recognition is lost at lower concentrations of NaOCl than those required to fragment Mus m 1.


OBJECTIVE
We sought to determine whether NaOCl had similar effects on recombinant (r)Fel d 1 and whether the loss of antibody recognition correlated with the loss of biologic activity, as measured with a basophil histamine release assay.


METHODS
Recombinant Fel d 1 was treated with increasing amounts of NaOCl, and the product of the reaction was analyzed by using SDS-PAGE, Western blotting, and ELISA. The biologic activity of NaOCl-treated rFel d 1 was analyzed with a basophil histamine release assay.


RESULTS
The protein fragmented at an NaOCl/rFel d 1 molar ratio of 7000, whereas cat-specific IgG recognition was lost at a lower molar ratio of 560. Basophil histamine release assays were performed to determine the effect of NaOCl on the biologic activity of rFel d 1. An NaOCl/protein molar ratio of 70 caused a significant reduction in histamine release from basophils of subjects with cat allergy. A molar ratio of 140 further inhibited histamine release by rFel d 1, suggesting a dose-response relationship between NaOCl and loss of biologic activity.


CONCLUSIONS
NaOCl modifies rFel d 1, resulting in loss of immunogenicity and attenuation of biologic activity, as measured by its ability to stimulate basophil histamine release.
Matsui
Elizabeth
E
Departments of Pediatrics and Medicine, Johns Hopkins School of Medicine, Johns Hopkins Hospital, 600 N. Wolfe Street, Baltimore, MD 21287, USA.
Kagey-Sobotka
Anne
A
Chichester
Kristin
K
Eggleston
Peyton A
PA
D000485:Allergens / Q000187:drug effects*; D000818:Animals; D001491:Basophils / Q000187:drug effects / Q000276:immunology; D002415:Cats; D006023:Glycoproteins / Q000187:drug effects* / Q000276:immunology*; D006197:Hair / Q000276:immunology; D006636:Histamine Release / Q000187:drug effects; D006801:Humans; D066298:In Vitro Techniques; D051379:Mice; D011994:Recombinant Proteins / Q000187:drug effects / Q000276:immunology; D012973:Sodium Hypochlorite / Q000494:pharmacology*
D000485:Allergens; D006023:Glycoproteins; D011994:Recombinant Proteins; D012973:Sodium Hypochlorite; C059296:Fel d 1 protein, Felis domesticus