A male volunteer named Conan was passively sensitized with IgE specific for Der f 1 (a potent house dust mite antigen/allergen). After an intradermal challenge with Der f 1, Conan displayed a typical skin lesion due to an immediate hypersensitivity reaction. Assess as either factually correct (= “true”) or incorrect (= “false”) the hypothetical results (11-20) obtained if the injection with sensitizing IgE was first preceded by an injection (at the same site) of Fc fragments of human IgE and then followed by the intradermal injection of allergen (Der f 1):
11. The reaction would be exacerbated due to the increased local concentration of IgE Fc fragments.
12. The reaction would be exacerbated due to the activation of complement.
13. The reaction would be exacerbated due to the augmented release of cytokines.
14. The reaction would be exacerbated due to the activation of macrophages and dendritic cells. 15. The reaction would be exacerbated, because the Fc fragments would activate NK cells.
16. The reaction would be exacerbated, because the Fc fragments would activate mast cells and/or basophils.
17. No reaction would occur because the Fc fragments would interact with the allergen and prevent it from gaining access to the sensitized mast cells.
18. No reaction would occur because the Fc fragments would interact with the IgE antibodies making their antigen-binding sites unavailable for binding to antigen.
19. No reaction would occur because the Fc fragments would interact with Fc? receptors on mast cells.
20. Conan would develop anaphylaxis.