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Updated: Jun 24, 2026

Isolation and Th17 Differentiation of Naïve CD4 T Lymphocytes
Published on: September 27, 2013
An overview of the immune system
1Department of Immunology, St Bartholomew's and the Royal London Hospital School of Medicine and Dentistry, Queen Mary and Westfield College, West Smithfield, EC1A 7BE, London, UK. Jackie.Parkin@bartsandthelondon.nhs.uk
The immune system defends against pathogens, but its dysfunction causes disease. This review covers normal immune functions in recognizing and fighting foreign invaders.
Area of Science:
- Immunology
- Microbiology
Background:
- Humans constantly encounter microorganisms via inhalation, ingestion, and skin contact.
- Disease development depends on pathogen virulence and host defense integrity.
Purpose of the Study:
- To review the normal function of the immune system.
- To explain how the immune system recognizes, repels, and eradicates pathogens.
Main Methods:
- Literature review of immune system function.
- Analysis of host-pathogen interactions.
Main Results:
- The immune system is a complex network of organs, cells, and molecules.
- Immune system dysfunction leads to immunodeficiency, infections, tumors, allergies, and autoimmune diseases.
Conclusions:
- Understanding normal immune function is crucial for comprehending disease states.
- The immune system's role in host defense is vital.
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