Study note
MicrobiologyImmune Response

Cell-mediated immunity and delayed hypersensitivity

THE CONTEXT
Cell-mediated immunity is an antigen-specific response mediated by effector T cells. Delayed hypersensitivity illustrates its cellular basis.

Effector cells

•
Cell-mediated immunity (CMI)* is mediated by effector T cells generated in response to the antigen.
•
Both activated helper T cells and cytotoxic T lymphocytes (CTLs) serve as effector cells in CMI.

Delayed hypersensitivity

•
Delayed hypersensitivity (DH) produces a skin lesion 48–72 hours after antigen administration.
•
The lesion is an indurated nodule with mononuclear cell infiltration.
•
DH is immunologically specific, has no relation to antibodies, and cannot be transferred passively by serum.
•
Its cellular basis was demonstrated by passive transfer in guinea pigs using leucocytes from sensitised donors.
Explore this chapter
NEETx
Learn. Practise. Remember.
HomeSubjectsPapersStudy notesQuick quiz