Question

Mast cells are filled with granules that contain histamine and involved in allergies. If antihistamines are used against the hay fever, which mechanism causes the allergic reaction?

• A. When an allergen binds to specific receptors on a mast cell, it induces cellular degranulation and the release of histamine into the tissue
• B. Seasonal allergens irritate the nasal mucosa and cause cellular infiltration by mast cells
• C. Mast cells phagocytose allergens that include cellular proliferation
• D. Mast cells move through tissues removing both histamines and antihistamines that may be causing the allergy
• E. Antihistamines are antibodies that bind to histamine to produce a complex, which is then removed from the tissue by mast cells

Answer 1

The correct option is A When an allergen binds to specific receptors on a mast cell, it induces cellular degranulation and the release of histamine into the tissue

Mast cells have IgE antibodies on their surface. Binding of allergen to the IgE antibodies on these cells drives the release of histamine from mast cells release that brings about the allergic symptoms. Histamines and other substances released from mast cells are responsible for allergic responses. Thus, the correct answer is option A.