How do mice show allergic reactions? - briefly
Mice manifest allergic responses through measurable signs such as elevated serum IgE, eosinophil infiltration, tissue swelling, and intensified scratching or respiratory distress, which are quantified by cytokine assays, histology, and behavioral monitoring.
How do mice show allergic reactions? - in detail
Mice manifest allergic responses through observable physiological and behavioral changes that can be quantified in laboratory settings. Typical signs include rapid scratching or grooming of the site of antigen exposure, erythema and edema of the ear or paw, increased respiratory rate, wheezing, and reduced body temperature during systemic anaphylaxis. In severe cases, mice may exhibit lethargy, loss of righting reflex, and rapid death.
Immunological markers provide objective evidence of hypersensitivity. Elevated serum IgE specific to the allergen is detected by ELISA. Mast cell degranulation releases histamine, prostaglandins, and leukotrienes, which can be measured in tissue extracts or plasma. Cytokine profiles shift toward a Th2 pattern, with increased IL‑4, IL‑5, IL‑13, and decreased IFN‑γ, detectable by multiplex assays or quantitative PCR.
Standard experimental models illustrate these manifestations:
- Passive cutaneous anaphylaxis – serum from sensitized mice is injected intradermally, followed by systemic antigen challenge; localized vascular leakage appears as a blue dye extravasation.
- Active systemic anaphylaxis – mice are sensitized and later challenged intraperitoneally; drop in core temperature and increased mortality quantify the reaction.
- Airway hyperresponsiveness model – aerosolized allergen induces bronchoconstriction; lung resistance is measured with plethysmography.
- Ear swelling assay – antigen injection into the ear pinna produces measurable thickness increase using a micrometer.
Histopathological examination corroborates clinical findings. Tissue sections reveal eosinophil infiltration, mast cell hyperplasia, and mucus hypersecretion in the respiratory tract. Flow cytometry of spleen or lymph node cells identifies expansion of IgE‑producing B cells and Th2 CD4⁺ T cells.
Collectively, the combination of behavioral observations, physiological recordings, immunological assays, and tissue analysis provides a comprehensive picture of how rodents display allergic reactions, enabling precise evaluation of allergen potency and therapeutic interventions.