Question

The antigen activates T-lymphocytes, which further secretes lymphokines. This kind of response can be seen in

• A. Hypersensitivity I.
• B. Hypersensitivity II.
• C. Hypersensitivity III.
• D. Hypersensitivity IV.

Answer 1

The correct option is D Hypersensitivity IV.

Hypersensitivity IV is also called as delayed type hypersensitivity which is cell-mediated and takes two to three steps to develop. In such a reaction the antigens are first recognized by CD4${}^{+}$ helper T-cells in a complex with antigen presenting cells. After the recognition of antigen, other Interleukins (IL), cytokines and lymphokines are produced by CD4${}^{+}$ cells. Therefore, the correct answer is option D.