Which white blood cell type is associated with allergic reactions and makes up about 2% of white blood cells?

Which white blood cell type is associated with allergic reactions and makes up about 2% of white blood cells?

• A. Eosinophils
• B. Neutrophils
• C. Lymphocytes
• D. Monocytes

Answer: (A)

Eosinophils are the white blood cell type most linked with allergic reactions. In allergic inflammation, they are recruited to the tissues and release toxic granule proteins, such as major basic protein, that help fight parasites but can also amplify tissue irritation and damage in allergies. They also release enzymes that modulate other inflammatory mediators from mast cells and basophils, helping to shape the late-phase allergic response. In a healthy adult, eosinophils normally make up about 1–6% of circulating white blood cells, with about 2% being a common approximation, which fits the prompt. Neutrophils are the primary responders to bacterial infections and comprise the majority of white blood cells, not specifically tied to allergy. Lymphocytes are the adaptive immune cells (T and B cells) involved in targeted immunity, not the typical 2% in allergies. Monocytes are the circulating precursors to macrophages and have a different role in phagocytosis and inflammation. Basophils can contribute to allergic reactions, but they are far less abundant than 2%.

Eosinophils are the white blood cell type most linked with allergic reactions. In allergic inflammation, they are recruited to the tissues and release toxic granule proteins, such as major basic protein, that help fight parasites but can also amplify tissue irritation and damage in allergies. They also release enzymes that modulate other inflammatory mediators from mast cells and basophils, helping to shape the late-phase allergic response. In a healthy adult, eosinophils normally make up about 1–6% of circulating white blood cells, with about 2% being a common approximation, which fits the prompt.

Neutrophils are the primary responders to bacterial infections and comprise the majority of white blood cells, not specifically tied to allergy. Lymphocytes are the adaptive immune cells (T and B cells) involved in targeted immunity, not the typical 2% in allergies. Monocytes are the circulating precursors to macrophages and have a different role in phagocytosis and inflammation. Basophils can contribute to allergic reactions, but they are far less abundant than 2%.