Spread the love
Reading Time: 3 minutes


… after 2 weeks of persistent cough with blood-stained sputum, constant fatigue, weight loss, and fever. He visited the physician who recommended him for the Mantoux test. He was injected with tuberculin intradermally and observed after 2 days for induration.

Positive Mantoux Reaction
Positive Mantoux Reaction

Delayed immune reaction is also known as hypersensitivity type 4. Unlike hypersensitivity type 1, 2 and 3. Delayed hypersensitivity does not involve the activities of antibodies. It is a cell-mediated reaction that involves the T-cells, Macrophages and the natural killer cells. When macrophages and dendritic cells recognize the antigen in the body. They engulf it and present it on their surface either as major histocompatibility II  or major histocompatibility I. The former is recognized by CD4+ T-helper cells which release cytokine that attracts more T- cells to the scene of action, subsequent inflammation of the skin ensues.

On the other hand, if the engulfed antigen is presented on the surface of macrophages or dendritic cells in form of MHC I, the natural killer is attracted to antigen presenting cells which eventually disrupt the antigen presenting cell.

natural killer cells


Examples of delayed immune reactions are observed in the following:

  • Contact dermatitis
  • Mantoux test
  • Crohn Disease
  • Diabetes mellitus type I

Contact dermatitis

Contact with the certain chemical as well as plants such as poison oak, poison ivy, and metals such as nickel has been implicated with causing itching, skin rashes and blisters. Individuals

Mantoux test   

This is a diagnostic test for tuberculosis. Tuberculin (a sterile solution containing inactivated products of the causal agent of tuberculosis: Mycobacterium tuberculosis). The solution is intradermally injected into patients showing symptoms of tuberculosis, and induration (hardening of the skin surface where tuberculin is injected) is observed 2 days.


Crohn Disease

This is also known as inflammatory bowel disease. It is accompanied by abdominal pain, diarrhea, and weight loss.

Diabetes mellitus type I

Diabetes is an ill-health condition caused by lack of insulin (a hormone responsible for making sugars in the body readily available to body cells where it is utilized for energy). In the case of Diabetes mellitus type 1, the body’s immune system attacks the beta cells in the pancreas which are responsible for insulin production.

See Also:

Cite this article as: Fagbohun, S.O., "HYPERSENSITIVITY: DELAYED IMMUNE REACTIONS," in ATG Ventures, 07/04/2019,

Help us improve our articles, we will appreciate your comment.



Attaincom Global Ventures Quiz, Let's get started!
Let’s get started!

Meet Bionuggets

Join BioNuggets on Facebook

Patronize Us



Type IV hypersensitivity reaction information | myVMC. myVMC. Published October 11, 2005. Accessed April 7, 2019.
Delayed Hypersensitivity Reactions: Background, Pathophysiology, Epidemiology. Emedicine. Accessed April 7, 2019.
ScienceDirect. Type IV hypersensitivity. Accessed April 7, 2019.

You may also like...