Which statement is true about eosinophils?

Which statement is true about eosinophils?

• A. They are involved in parasitic infections and allergic responses
• B. They are the most abundant white blood cells
• C. They function primarily as phagocytes
• D. They release histamine

Answer: (A)

Eosinophils are a type of white blood cell whose main roles include defense against parasitic infections and participation in allergic reactions. They contain granules with proteins that can damage parasites, especially helminths, and their activity is heightened in parasitic infections as well as in allergic states when IgE-coated targets recruit them to tissues. They are not the most abundant white blood cells—that distinction goes to neutrophils in a normal blood count. They’re also not primary phagocytes; neutrophils do most of the phagocytosis, while eosinophils contribute by releasing toxic granule contents to attack parasites and modulate inflammation. Histamine release is mainly a function of basophils and mast cells, not eosinophils. So, the statement that eosinophils are involved in parasitic infections and allergic responses is the accurate one.

Eosinophils are a type of white blood cell whose main roles include defense against parasitic infections and participation in allergic reactions. They contain granules with proteins that can damage parasites, especially helminths, and their activity is heightened in parasitic infections as well as in allergic states when IgE-coated targets recruit them to tissues. They are not the most abundant white blood cells—that distinction goes to neutrophils in a normal blood count. They’re also not primary phagocytes; neutrophils do most of the phagocytosis, while eosinophils contribute by releasing toxic granule contents to attack parasites and modulate inflammation. Histamine release is mainly a function of basophils and mast cells, not eosinophils. So, the statement that eosinophils are involved in parasitic infections and allergic responses is the accurate one.