Vaccination

Abstract

Immunisation is the process of introducing material into a host in order to elicit a protective response by the immune system. The material used in the vaccine is typically derived from a pathogenic microorganism that is modified in some way so that it does not cause disease. This material contains antigens (i.e. molecules recognised by lymphocytes). After immunisation, the T and B lymphocytes capable of recognising the material in the vaccine become activated, differentiate into effector cells and act to remove the antigens from the body. Activated B cells begin to produce antibody and eventually become long‐lived memory B cells that migrate to the bone marrow and continue to secrete antibody. Activated T cells recognise and destroy infected cells and can also develop into long‐lived memory T cells. On subsequent exposure to the same pathogen (and antigens), the memory response is quicker and far stronger than a primary response. It is this memory response that protects the host from disease.

Key Concepts

  • Vaccines have saved more lives than any other medical invention.
  • Vaccines simulate a real infection so that the immune system can develop a protective response against a specific pathogen.
  • Vaccination provides long‐lived immunologic memory so that the immune response during a subsequent exposure to a pathogen is more rapid and much stronger.
  • Protective immunity is a complex process that differs for each pathogen.
  • While orders of magnitude safer than the diseases they prevent, vaccines may cause side effects.

Keywords: immunisation; vaccination; vaccines; adjuvants; antigen; immune response; humoral immunity; antibodies; cellular immunity

Figure 1. Overview of vaccination. Disease‐causing microorganisms are combined with adjuvants (immunostimulatory compounds) and injected into healthy individuals in order to provoke an immune response. The vaccine elicits pathogen‐specific immunity through the development of long‐lived memory cells (B cells producing antibodies and T cells capable of destroying infected cells). These memory cells are primed to immediately respond when the vaccine recipient encounters the pathogen again. The response to this subsequent exposure is typically so strong that the pathogen is eliminated before infection and clinical disease can occur.
close

References

College of Physicians of Philadelphia (2017), Timeline of Vaccines. Philadelphia, PA.

Cova L (2017) Present and future DNA vaccines for chronic hepatitis B treatment. Expert Opinion on Biological Therapy 17: 185–195.

FDA (2017) List of Vaccines Licensed for Use in the United States, vol. 2017. FDA. https://www.fda.gov/BiologicsBloodVaccines/Vaccines/ApprovedProducts/ucm093833.htm

Fenner F (1988) Smallpox and Its Eradication. Geneva: World Health Organization.

Geison GL (1978) Pasteur's work on rabies: reexamining the ethical issues. Hastings Center Report 8: 26–33.

Gordon S (2016) Elie Metchnikoff, the man and the myth. Journal of Innate Immunity 8: 223–227.

Holmgren J, Parashar UD, Plotkin S, et al. (2017) Correlates of protection for enteric vaccines. Vaccine 35: 3355–3363.

Jenner E (1798) An Inquiry into the Causes and Effects of the Variolae Vaccinae: A Disease Discovered in Some of the Western Counties of England, Particularly Gloucestershire, and Known by the Name of the Cow Pox. London: Sampson Low.

Leroux‐Roels G (2010) Unmet needs in modern vaccinology: adjuvants to improve the immune response. Vaccine 28 (Suppl 3): C25–C36.

Oberg AL, Kennedy RB, Li P, Ovsyannikova IG and Poland GA (2011) Systems biology approaches to new vaccine development. Current Opinion in Immunology 23: 436–443.

Owen JA, Punt J and Stranford SA (2013a) The immune response in space and time. In: Kuby Immunology, 7th edn. New York: W.H. Freeman and Company.

Owen JA, Punt J and Stranford SA (2013b) Infectious diseases and vaccines. In: Kuby Immunology, 7th edn. New York: W.H. Freeman and Company.

Plotkin SA (2010) Correlates of protection induced by vaccination. Clinical and Vaccine Immunology 17: 1055–1065.

Plotkin SA (2013) Complex correlates of protection after vaccination. Clinical Infectious Diseases 56: 1458–1465.

Plotkin SA, Orenstein WA and Offit PA (2017) Vaccines, 7th edn. Philadelphia, PA: Elsevier/Saunders.

Pulendran B (2014) Systems vaccinology: probing humanity's diverse immune systems with vaccines. Proceedings of the National Academy of Sciences of the United States of America 111: 12300–12306.

United States Department of Health and Human Services (2017), vol. 2017. https://vaers.hhs.gov/

Zafack JG, De Serres G, Kiely M, et al. (2017) Risk of recurrence of adverse events following immunization: a systematic review. Pediatrics 140 (3): e20163707. DOI: 10.1542/peds.2016-3707.

Further Reading

NIAID (2012) The Jordan Report: Accelerated Development of Vaccines 2012. US Department of Health and Human Services, National Institutes of Health, National Institute of Allergy, Immunology, and Infectious Diseases.

Owen JA, Punt J and Stranford SA (2013) Kuby Immunology, 7th edn. New York: W.H. Freeman and Company.

Paul WE (2013) Fundamental Immunology, 7th edn. Philadelphia, PA: Lippincott Williams and Wilkins.

Plotkin SL and Orenstein WA (2017) Vaccines, 7th edn. China: Elsevier Saunders.

Contact Editor close
Submit a note to the editor about this article by filling in the form below.

* Required Field

How to Cite close
Kennedy, Richard(Apr 2018) Vaccination. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1002/9780470015902.a0000489.pub3]