Question

The antibody-dependent cytotoxicity seen in?
A) Local anaphylaxis
B) Generalise anaphylaxis
C) Immune complex reaction
D) Non-compatible-blood transfusion

Answer 1

Hint: Antibodies can cooperate with the cellular branch of the immune system by binding and recruiting the activities of cytotoxic cells, most often natural killer cells this is called antibody-dependent cell-mediated cytotoxicity.


Complete step-by-step answer:

If we receive blood that is not compatible with our blood, then our body produces antibodies to destroy the donor’s blood cells. This is done by antibodies-dependent cell-mediated immunity. This is called a transfusion reaction. The blood that we receive in a transfusion must be compatible with our blood. This is a part of type II hypersensitivity. It destroys host cells, either by lysis or toxic mediators so Type II hypersensitivity is also called a cytolytic or cytotoxic reaction.
Local Anaphylaxis or atopy is a very rapid, life-threatening, severe whole-body allergic reaction. It shows Ig-E mediated humoral antibody responses.
Generalize anaphylaxis affects multiple organ systems, severe, immediate –type, and is characterized at its most severe by branchospasm, and upper airway.
Immune complex reaction: In type III hypersensitivity reactions, an abnormal immune response is mediated by the formation of antigen-antibody aggregates called immune complexes. They can precipitate in various tissues such as joints, and vessels and trigger the classical complement pathway.


Therefore the correct answer is Option A.

Note: > Infected cells with antibodies bound to them can be killed by natural killer cells(NK cells ). NK cells can recognize and destroy antibody-coated target cells in a process called antibody-dependent cell-mediated cytotoxicity(ADCC). This is triggered when the antibody bound to the surface of the cell interacts with Fc receptors on the NK cell. NK cells express the receptor, which recognizes the Ig1 and Ig-3 antibody subclasses. The binding of antibodies to this receptor activates the NK cells. The NK cells release cytoplasmic granules containing perforin and granzymes and induce the death of antibody-coated target cells.