A 30-year-old man is known for his large appetite. At a luncheon meeting, he notices that all the cookies contain nuts, which the other diners have ordered knowing that he would not eat them because he would develop blotchy, erythematous, slightly edematous, pruritic plaques on his skin. These plaques would form and then fade within 2 hours. If the man eats the cookies, which of the following sensitized cells would release a mediator that produces these skin lesions?
If the man eats the cookies, he will have hives, or urticaria, from an allergy to an antigen in the nuts. This causes a type I hypersensitivity reaction in which IgE antibodies are bound to the IgE receptor on mast cells. IgE-sensitized mast cells degranulate when the antigen is encountered. CD4+ helper lymphocytes are mainly part of the more extended cell-mediated or humoral immune reactions in adaptive immune responses. Natural killer cells mediate antibody-dependent cell-mediated cytotoxicity and lyse major histocompatibility complex class I-deficient target cells. Neutrophils may become attracted to this site, but they are not the sensitized cells. Plasma cells secrete the IgE antibodies but do not release the mediators for allergic reactions.
CD4+ lymphocyte
Mast cell
Natural killer cell
Neutrophil
Skin