Peanut allergy was induced in mice on the C57Bl/6 background (IAb) with 4 weekly oral gavage feedings of peanut protein and cholera toxin. After a two-week rest period, sensitized animals were challenged by intraperitoneal injection with crude peanut extract (CPE) and monitored for anaphylaxis. Clinical indicators of peanut allergy include decreased body temperature, scratching, swollen eyes, decreased movement and responsiveness, and moribund condition. We evaluated plasma histamine, total IgE, peanut-specific IgE, and peritoneal albumin levels as in vivo indicators of mast cell degranulation and vascular permeability.
Targeted genes and phenotypes
CD34-/-
Normally a surface marker of hematopoietic stem cells, mast cells, eosinophils and DCs, required for efficient cell migration. Mice exhibit attenuation of most mucosal inflammatory disease models.
CD103-/-
Alpha-chain of integrin expressed by mucosal DCs and T cells which facilitates binding to mucosal epithelial cells; Mice exhibit exacerbated Th2 inflammatory responses.
IL7-Ra-/-
Required for T cell homing and efficient T and B cell development. Mice exhibit impaired adaptive immune responses.
L-Selectin-/-
Adhesion molecule required for appropriate localization of naïve lymphocytes to primary lymphoid tissue. Mice exhibit impaired primary adaptive immune responses.
PSGL-1-/- and E-Selectin-/-
Adhesion molecules required for efficient homing of inflammatory cells to the sites of inflammation. Mice exhibit attenuated inflammatory responses.