IgE Mediated, Acute

Type Type I
Time frame (exogenous exposure) few minutes (– 8-12 hours)(can be biphasic)
Immune Reactant IgE mediated
Antigen Soluble
Effector forDamage  Pathway Mast CellsNaïve B-cell as APC (IL4, IL5): Naïve CD4+  TH2 (IL4)  Plasma B cell (IgE)  coat Mast cells  release histamine. After removal of Ag: continued release of cytokine + recruitment of granulocytes  delayed/biphasic response
Note o   Often has genetic pre.o   EFAR (onset order): Eczema → Food Allergy → Asthma → Rhinitis o   Onset can be any age