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What is Delayed hypersensitivity involves: and explain in detail?
Ans. is 'd' i.e., Lymphocytes (Ref: Ananthanarayan, 9th/e, p. 167 and 8th/e, p. 168)* Reaction is mediated by sensitized T-lymphocytes which, on contact with specific antigen, release lymphokines that cause biological effects on macrophages, leucocytes and tissue cells.* Delayed type by CD4 Th1 cell.