Prausnitz-kustner (PK) reaction was used to demonstrate -: (A) IgA, (B) IgG, (C) IgM, (D) IgE
Answer is D. Ans. is 'd' i.e., IgE o IgE is homocytotropic i.e. species specific. Only human IgE can fix to the surface of human cells. This is the basis of the Prausnitz-Kustner (PK) reaction, which was the original method for detecting atopic antibody.