The most important cells in type I hypersensitivity:
High-Yield Explanation
Ans. is 'b' i.e., Mast cells(Ref: Ananthanarayan, 9th/e, p. 162; Robbin's 7th/e, p. 206)* Priming Ag - Antigen presenting cell - T cell - Th 2 - B cell - IgE - Mast cell coated with IgE (Fc).* Shocking dose - IgE (Fab) binds to Ag - Mast cell degranulation.* Primary mediator (Histamine, Serotonin, chemotactic factor) and secondary factor (PG and cytokines) - Typical manifestations like Anaphylaxis etc.