Peanut- and cow's milk-specific IgE, Th2 cells and local anaphylactic reaction are induced in Balb/c mice orally sensitized with cholera toxin.
BACKGROUND
The development of animal models developing specific immunoglobulin (Ig)E presenting the same specificity as human IgE and similar clinical symptoms as those observed in allergic patients are of great interest for the understanding of mechanisms involved in the induction and regulation of food allergy.


METHODS
Balb/c female mice were sensitized with whole peanut protein extract (WPPE) by means of intraperitoneal (i.p.) injections with alum or gavages with cholera toxin (CT). The WPPE specific IgE, IgG1 and IgG2a were monitored. Th2 cells activation was analysed assaying interleukin (IL)-4 and IL-5 vs IFNgamma on reactivated splenocytes. Local anaphylactic reaction was evaluated by assaying histamine in faecal samples. The oral sensitization protocol was further extended to cow's milk proteins (CMP).


RESULTS
Balb/c mice developed high peanut-specific IgE and IgG1 responses either after i.p. or oral sensitizations. In both cases, antibodies were specific to polymer of glycinin fragments, containing polypeptides from Ara h3/4, and to a lesser extent to Ara h1 and Ara h2. Interleukin-4 and IL-5 production were evidenced. Balb/c mice could also be sensitized to CMP, as demonstrated by CMP-specific IL-4 and IL-5 secretions and induction of IgE specific for whole caseins, beta-lactoglobulin, serum bovine albumin and lactoferrin. Of interest was the occurrence of a local anaphylactic reaction in the peanut and CM models.


CONCLUSIONS
In contrast with previous authors, Balb/c mice were sensitized and evidenced an allergic reaction after oral administrations of peanut or CMP plus CT, providing an interesting model for further studies on immunopathogenic mechanisms.
Adel-Patient
K
K
Laboratoire Inra d'Immuno-Allergie Alimentaire, CEA de Saclay, Gif sur Yvette cedex, France.
Bernard
H
H
Ah-Leung
S
S
Créminon
C
C
Wal
J-M
JM
D000707:Anaphylaxis / Q000209:etiology*; D000818:Animals; D000918:Antibody Specificity; D010367:Arachis / Q000737:chemistry; D002772:Cholera Toxin / Q000276:immunology*; D016207:Cytokines / Q000378:metabolism; D005243:Feces / Q000737:chemistry; D005260:Female; D006632:Histamine / Q000032:analysis; D007114:Immunization; D007073:Immunoglobulin E / Q000032:analysis* / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D016269:Milk Hypersensitivity / Q000276:immunology* / Q000473:pathology; D008894:Milk Proteins / Q000276:immunology; D009061:Mouth Mucosa / Q000276:immunology*; D021183:Peanut Hypersensitivity / Q000276:immunology* / Q000473:pathology; D010936:Plant Extracts / Q000276:immunology; D013154:Spleen / Q000276:immunology / Q000378:metabolism; D018418:Th2 Cells / Q000473:pathology*
D016207:Cytokines; D008894:Milk Proteins; D010936:Plant Extracts; D007073:Immunoglobulin E; D006632:Histamine; D002772:Cholera Toxin