THE HUMAN IMMUNE SYSTEM
IMMUNE RESPONSE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Mast Cell
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T-Cell
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Plasma Cell
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B-Cell
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Detailed explanation-1: -Mast cells are fascinating, multifunctional, bone marrow-derived, tissue-dwelling cells. They can be activated to degranulate in minutes, not only by IgE and antigen signaling via the high-affinity receptor for IgE, but also by a diverse group of stimuli.
Detailed explanation-2: -The high affinity IgE receptor (FcepsilonRI) expressed on the cell surface of mast cells and basophils is the key molecule in triggering the IgE-mediated allergic reaction.
Detailed explanation-3: -Mast cells express the activating IgG receptor FcRIIa (CD32a) in the resting state, and, in the presence of interferon-, the high affinity activating FcRI (CD64).
Detailed explanation-4: -The high-affinity receptor for IgE, FcRI, as expressed by mast cells and basophils, consists of an IgE-binding chain, in which the two extracellular domains bind IgE, a chain, which spans the plasma membrane four times and functions as a signal amplifier37, and two identical and largely intracellular chains38.
Detailed explanation-5: -Type I hypersensitivity is also known as an immediate reaction and involves immunoglobulin E (IgE) mediated release of antibodies against the soluble antigen. This results in mast cell degranulation and release of histamine and other inflammatory mediators.