: The ability to limit or shut down the immune response once the threat is neutralized to prevent tissue damage. 3. Clinical Importance and Future Directions
: This "second line" of defense is highly specific and develops over time. It relies on B cells , which produce antibodies, and T cells , which can directly kill infected cells. A hallmark of adaptive immunity is its ability to create "immunological memory," allowing the body to respond faster and more effectively upon re-exposure to the same pathogen. 2. Core Principles of Immunology Immunology
: The ability to identify and fight off foreign infections. : The ability to limit or shut down
: Where the system mistakenly attacks "self" tissues. It relies on B cells , which produce
The immune system is generally categorized into two interconnected systems: innate and adaptive immunity.
Immunology is the branch of biomedical science that explores the complex network of cells, tissues, and organs that constitute the immune system. Its primary function is to protect the host from pathogens such as bacteria, viruses, and parasites while maintaining a delicate balance of "self-recognition" to avoid attacking the body's own tissues. This essay explores the fundamental principles of immunity, the distinction between its two primary arms, and the importance of this field in modern medicine. 1. The Two Arms of the Immune System
To function correctly, a healthy immune system must adhere to four essential principles: