Lymphocytes: The Key Players in the Adaptive Immune System
Definition
Lymphocyte
Lymphocytes are a type of white blood cell critical for the adaptive immune response.
- Lymphocytes are a type of white blood cell that make up about 25% of the white blood cells in your body.
- They are small cells with a large, round nucleus and a thin rim of cytoplasm.
- Lymphocytes are found in two main places:
- Bloodstream: They circulate throughout the body, ready to respond to infections.
- Lymphatic System: This network of vessels and nodes drains excess fluid from tissues and acts as a hub for immune activity. Lymph nodes, in particular, are rich in lymphocytes and swell during infections as these cells multiply to fight pathogens.
The lymphatic system is like a highway for immune cells, allowing them to travel quickly to sites of infection.
Types of Lymphocytes
There are two primary types of lymphocytes, each with a unique role in the immune response:
- B-Lymphocytes (B-Cells):
- Function: Produce antibodies, proteins that specifically target and neutralize pathogens.
- Location: Mature in the bone marrow.
- T-Lymphocytes (T-Cells):
- Function: Assist in activating B-cells and directly attack infected or abnormal cells.
- Location: Mature in the thymus.
B-cells produce antibodies, while T-cells help coordinate the immune response.
How Do Lymphocytes Produce Antibodies?
- Antibodies are Y-shaped proteins that bind to specific molecules on pathogens, called antigens.
- This binding is highly specific, like a lock and key.
Steps in Antibody Production
- Recognition:
- Each B-cell is programmed to produce one type of antibody.
- When a pathogen enters the body, its antigens are recognized by a matching B-cell.
- Activation:
