Immune cells are the body's defense force, working tirelessly to protect against infections and diseases. They are a crucial part of the immune system, a complex network also involving organs, proteins, and chemicals. These cells originate from stem cells in the bone marrow and differentiate into various types of white blood cells, each with specialized roles.
Types of Immune Cells
Several key categories of immune cells exist, each contributing to the body's defense mechanisms:
- Lymphocytes: These are a major player, including:
- T cells: Coordinate immune responses and directly attack infected cells.
- B cells: Produce antibodies that neutralize pathogens.
- Natural Killer (NK) cells: Identify and destroy infected or cancerous cells.
- Granulocytes: These cells contain granules filled with enzymes that help destroy pathogens. Examples include:
- Neutrophils: The most abundant type, quickly responding to infections.
- Basophils & Eosinophils: Involved in allergic reactions and parasitic infections.
- Monocytes/Macrophages: These cells engulf and digest pathogens and cellular debris. Monocytes circulate in the blood, while macrophages reside in tissues.
How Immune Cells Work
Immune cells use various methods to combat threats:
- Phagocytosis: Cells like neutrophils and macrophages engulf and destroy pathogens.
- Antibody Production: B cells create antibodies that bind to specific pathogens, marking them for destruction.
- Cell-Mediated Immunity: T cells directly attack infected cells or help coordinate other immune responses.
- Cytokine Release: Immune cells release signaling molecules (cytokines) that regulate immune responses and communicate with other cells.
The immune system's response is a carefully orchestrated process involving the coordinated action of various immune cells and other components. (As stated in the provided text: "Your immune system is a network of organs, white blood cells, proteins and chemicals that work together to protect you from invaders (like germs) that can…") The immune system detects and responds to a vast array of threats, from viruses and bacteria to cancer cells and parasitic worms. (As stated in the provided text: "It detects and responds to a wide variety of pathogens, from viruses to bacteria, as well as cancer cells, parasitic worms, and also objects such as wood…") Immune cells are sometimes referred to as white blood cells or leukocytes. (As stated in the provided text: "Immune cells are sometimes called white blood cells or leukocytes.")
