Primary vs Secondary Immune Response- 12 Differences

In a primary immune response, naive B cells are stimulated by antigen, become activated, and differentiate into antibody-secreting cells that produce antibodies specific for the eliciting antigen. A secondary immune response is elicited when the same antigen stimulates memory B cells, leading to the production of greater quantities of specific antibodies that are produced in the primary response.

Some of the differences between Primary and Secondary Immune Responses are as follows:

Differences between Primary and Secondary Immune Response
Figure: A schematic diagram showing a primary and secondary response, Source: Textbook of Microbiology and Immunology, 2/e, Parija

Primary vs Secondary Immune Response

S.N.CharacteristicsPrimary Immune Response Secondary Immune Response
1DefinitionThe primary Immune Response is the reaction of the immune system when it contacts an antigen for the first time.Secondary Immune Response is the reaction of the immune system when it contacts an antigen for the second and subsequent times.
2AppearanceAppears mainly in the lymph nodes and spleen.Appears mainly in the bone marrow and then, in the spleen and lymph nodes.
3OccurrenceThis occurs in response to the primary contact of the antigen.This occurs in response to the second and subsequent exposure to the same antigen.
4Antibody PeakThe antibody level reaches its peak in 7-10 days.The antibody level reaches its peak in 3-5 days.
5Affinity of AntibodyLow affinity to their antigens.High affinity to their antigens.
6Responding CellsNaive B cells and T cellsMemory B cells
7AntibodiesBoth thymus-dependent and thymus-independent antibodies are involved in the primary immune response.Only thymus-dependent antibodies are involved in the secondary immune response.
8Lag PhaseLong (4-7 days)Short (1-4 days)
9Types of AntibodiesA large amount of IgM and a small amount of IgG are produced during the primary immune response.A large amount of IgG, a small amount of IgM, IgA, and IgE are produced during the secondary immune response.
10Amount of AntibodyFew antibodies are produced in the primary immune response.100-1000 times more antibodies are produced in the secondary immune response.
11Strength of the ResponseThe primary immune response is usually weaker than the secondary immune response.The secondary immune response is stronger.
12Antibody levelAntibody level declines to the point where it may be undetectable.The antibody level tends to remain high for longer.
Differences between Primary and Secondary Immune Response
Figure: Primary and secondary humoral immune responses, Source: Cellular and Molecular Immunology, Abbas, 9th Edition.

References

  1. http://www.microbiologynotes.com/differences-between-primary-and-secondary-immune-response/
  2. https://www.mytutor.co.uk/answers/867/A-Level/Biology/What-is-the-difference-between-the-primary-and-secondary-immune-response
  3. http://pediaa.com/difference-between-primary-and-secondary-immune-response/
  4. https://www.differencebetween.com/difference-between-primary-and-vs-secondary-immune-response/
  5. http://www.yourarticlelibrary.com/difference/difference-between-primary-immune-response-and-secondary-immune-response-explained/11492
  6. http://www.yourarticlelibrary.com/immunology/difference-between-primary-and-secondary-immune-response-immune-response/27758
  7. http://biotech4you.com/important-summary/136-difference-between-primary-immune-response-and-secondary-immune-response
  8. https://sites.ualberta.ca/~pletendr/tm-modules/immunology/70imm-primsec.html
  9. http://www.els.net/WileyCDA/ElsArticle/refId-a0000947.html
  10. https://www.quora.com/What-is-primary-and-secondary-immune-response
  11. http://www.biologydiscussion.com/immunology/primary-and-secondary-immune-responses/56016
  12. http://www.chegg.com/homework-help/questions-and-answers/differences-primary-secondary-immune-response-q5742519
  13. https://forums.studentdoctor.net/threads/primary-vs-secondary-immune-response.288539/
  14. http://www.newhealthadvisor.com/Primary-Immune-Response.html

3 thoughts on “Primary vs Secondary Immune Response- 12 Differences”

Leave a Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.