Which dermal cells are involved in allergic reactions?

Mast cells play a crucial role in allergic reactions due to their ability to release histamine and other chemical mediators in response to allergens. When an allergen enters the body and is recognized by the immune system, mast cells are activated and degranulate, which releases substances that cause the symptoms associated with allergies, such as itching, swelling, and inflammation.

While cells like lymphocytes are involved in the immune response and help develop the body’s adaptive immunity, they do not have the direct role that mast cells do in the immediate response to allergens. Langerhans cells are part of the skin’s immune defense, but they primarily function as antigen-presenting cells and do not directly mediate allergic responses. Fibroblasts are involved in the maintenance of connective tissues and wound healing, and are not directly implicated in allergic reactions either.

Therefore, the significance of mast cells in allergens and their immediate hypersensitivity reactions validates them as the correct choice for this question.