IGHE and cold urticaria: There is precedent for synthesis of IgE that is either intrinsically abnormal or perhaps reactive with an unknown autoantigen; for example, it has been shown that isolated monomeric IgE of some patients with cold urticaria can passively transfer the disease,[41] that is, the IgE binds to normal mast cells of a recipient and renders them "cold sensitive" so that mast cells then degranulate upon a change in temperature.