Primary and secondary immune response

What does primary immune response respond to

newly encountered antigen

What does secondary immune response respond to

previously encountered antigen

During clonal expansion, what do T and B cells form?

memory cells

How would antibody concentration fluctuate depending on the primary and secondary response?

Why does the primary immune response take so long?

A lot of time and energy is required for:

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* clonal selection and expansion of specific T and B cells
* antibody synthesis

Roughly how long does it take for antibodies to appear in the blood after the foreign antigen has entered the body?

10-17 days

What does the time delay of the primary immune response cause?

Patient experiences symptoms

What is the life span of plasma cells

short

How does the secondary immune response work?

* If the ^^**same foreign antigen**^^ is found in the body a **second time**, the ^^**B memory cells**^^ **recognise** the antigen

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* B memory cells divide very quickly and differentiate into plasma cells (to produce antibodies) and more memory cells

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* This response is **very quick**, meaning that **the** ^^**infection can be destroyed and removed** ^^before the pathogen population increases too much and symptoms of the disease develop

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* This response to a previously encountered pathogen is, **relative to the primary immune response, extremely fast**

What do you call the immunity you were born with

Innate immunity

What do T memory cells produce?

Memory helper T cells

Memory killer T cells