Which WBC type is linked to allergic reactions and parasitic infections?

Which WBC type is linked to allergic reactions and parasitic infections?

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

Answer: (C)

Eosinophils are the WBC type that bridge both allergic reactions and parasitic infections. They are specialized for fighting parasites, especially helminths, and are recruited to sites of allergic inflammation as part of the late-phase response. When activated (often via IL-5 and IgE-related pathways), eosinophils release toxic granule proteins like major basic protein and eosinophil cationic protein that damage parasites and help control infection. In allergies, these same cells release mediators that sustain inflammation and contribute tissue-damaging effects if the response is excessive. Basophils mainly release histamine in allergies, neutrophils tackle bacterial infections, and monocytes/macrophages handle phagocytosis and chronic inflammation, but eosinophils uniquely address both parasite defense and allergic inflammation, making them the best fit.

Eosinophils are the WBC type that bridge both allergic reactions and parasitic infections. They are specialized for fighting parasites, especially helminths, and are recruited to sites of allergic inflammation as part of the late-phase response. When activated (often via IL-5 and IgE-related pathways), eosinophils release toxic granule proteins like major basic protein and eosinophil cationic protein that damage parasites and help control infection. In allergies, these same cells release mediators that sustain inflammation and contribute tissue-damaging effects if the response is excessive. Basophils mainly release histamine in allergies, neutrophils tackle bacterial infections, and monocytes/macrophages handle phagocytosis and chronic inflammation, but eosinophils uniquely address both parasite defense and allergic inflammation, making them the best fit.