Primary response

Definition

The primary response is the body's initial immune reaction to a novel antigen. It involves the activation of naive B and T cells and takes longer to develop compared to subsequent exposures.

5 Must Know Facts For Your Next Test

1. The primary response typically takes about 7-14 days to peak.
2. Memory cells are formed during the primary response, which help in faster secondary responses.
3. During the primary response, IgM antibodies are produced first, followed by IgG antibodies.
4. The primary response can be elicited by natural infection or vaccination.
5. A major characteristic of the primary response is that it involves a lag phase where no detectable antibody is present.

Related terms

Secondary Response:

A faster and more robust immune reaction upon re-exposure to an antigen due to memory cell activation.

Memory Cells: Long-lived lymphocytes that remember past infections and enable a quicker immune response upon re-exposure.

Antigen:

Any substance that elicits an adaptive immune response by being recognized as foreign by the immune system.