Question

3. Acquired lmmunity

A) Discuss immunity acquired by vaccination

B) Discuss immunity acquired by disease exposure

C) Discuss. Acquired immunity Deficiency syndrome

D) Discuss the function of T-Cells

Answer 1

Acquired immunity/Adaptive immunity

It is the defense mechanism of our body which are not present at birth and acquired during the life .

It can be achieved from

• Vaccination
• Disease exposure
• Another person's antibodies

A) Immunity acquired by vaccination

By vaccination we can get artificial acquired immunity. It can be active or passive.

In active artificial immunity, antibodies are made by our own body in response to the vaccination. In this, we inject weakened or mild form of pathogen which stimulates immune system to create plasma cells and they produce specific antibodies.

In passive artificial immunity, antibodies produced by other animals are directly injected to our bloodstream. E.g: tropical diseases, rabies.

B) Immunity acquired by disease exposure

When a disease producing agent enters our body, our body's defence mechanisms recognize them as antigens and produce specific antigen against them. This is an example of natural active immunity.

Immune response occurring when the body encounters with the organism for the first time is termed as primary immune response and immune response imported on the subsequent exposures is termed as secondary immune response.

Primary response takes more time to get established, few antibodies are produced and it declines rapidly. But secondary response will take its action more rapidly , more antibodies will be produced and it will remain for a longer time.

C) Acquired Immunity deficiency syndrome

It is a condition caused by a virus called Human immunodeficiency virus (HIV)

This virus attack body's immune system and destroy the immune cells which plays important role in the defence. It will result in a deficiency of immunity.

When our immune system is not working properly, e will have an increased chance of infections. Even the mild pathogens will invade our immune mechanisms and cause serious illness.

So this will produce a spectrum of conditions ranging from mild influenza-like illness to serious life threatening opportunistic infections.

D) Function of T cells

There are several types of T cells and each have different functions

**Cytotoxic T cells

Destroy viral infected cells and tumor cells

**Helper T cells

Assist other white blood cells in immunologic processes(Stimulation of cytotoxic and suppressor T cells, stimulation of B cells)

**Memory T cells

Antigen specific T cells which persist long term after an infection has resolved.

**Regulatory T cells

Regulate our suppress other immune cells. These cells helps to prevent autoimmune disorders.