On subsequent encounter with the drug, a hapten–carrier complex is formed again, which then crosslinks preformed drug-specific IgE on mast cells, activating a cascade for allergic reaction.

Mast cells preform and store approximately 500 secretory granules and many others which are made de novo and are released locally and in systemic circulation when specific antigens react with IgE ...

Mast said there is a “real threat” of sleeper cells by operatives "from a host of different countries,” but suggested the Trump administration can garner major intelligence by addressing this.

Iran had warned Washington about the activation of terrorist sleeper cells in the United States a few days before the U.S. attack, NBC News reported on Monday, citing unnamed sources. U.S ...

Urticaria pigmentosa is a rash, most common in children and young adults, characterized by reddish-brown, gray, or purple lesions. Learn about its causes, symptoms, diagnosis, treatment, and more.