Question

What type of immune response does poison ivy primarily induce, leading to the activation of CD4+ T cells and an inflammatory response?

A. Type IV (delayed-type) hypersensitivity
B. Type I (immediate) hypersensitivity
C. Type III hypersensitivity
D. Type II hypersensitivity

Answer 1

Poison ivy primarily induces a Type IV (delayed-type) hypersensitivity immune response, activating CD4+ T cells and causing an inflammatory response.

Step-by-step explanation:

The immune response that poison ivy primarily induces, leading to the activation of CD4+ T cells and an inflammatory response, is Type IV (delayed-type) hypersensitivity.

During the initial exposure to poison ivy, sensitization occurs, stimulating helper T cells and resulting in the production of memory helper T cells. Upon secondary exposure, these memory T cells become reactivated and release inflammatory cytokines that stimulate macrophages and cytotoxic T cells, causing an inflammatory lesion at the exposed site.

This type of immune response is characterized by a cell-mediated immune response that takes approximately one to two days after secondary exposure to manifest fully.