OBJECTIVE LIFE SCIENCE
SIGNALLING IMMUNOLOGY CANCER
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
early
|
|
|
late
|
|
|
Either A or B
|
|
|
None of the above
|
Detailed explanation-1: -This reaction is also known as delayed-type hypersensitivity due to its characteristic longer time period to appear following antigen exposure. The reaction takes longer than all other types because of the length of time required to recruit cells to the site of exposure – around 24 to 72 hours.
Detailed explanation-2: -Delayed-type hypersensitivity (DTH) is defined as the recruitment of T cells into tissues to be activated by antigen-presenting cells to produce cytokines that mediate local inflammation. CD8+ T cells are now known to mediate DTH responses in allergic contact dermatitis, drug eruptions, asthma, and autoimmune diseases.
Detailed explanation-3: -Type IV hypersensitivity is a type of delayed-type immune response, in which the immune system responds to an antigen several hours or days after exposure. It is also known as cell-mediated hypersensitivity because tissue damage involves T cells.