Introduction to Lymphatic and Immune System

Immunity refers to the body’s ability to resist infections and diseases. All cells and tissues that provide immunity collectively form the immune system.

Immune responses can be innate — nonspecific defenses present at birth, or adaptive — specific responses acquired over time.

The lymphatic system is a vital component, facilitating the adaptive immune response and some elements of innate immunity.

It comprises four main components: lymph, immune cells, lymphatic vessels, and lymphatic tissues and organs.

Lymph is a clear fluid that transports immune cells and plasma proteins.

Immune cells include lymphocytes, macrophages, and dendritic cells, among others.

Lymphocytes are white blood cells that facilitate the adaptive immune response. Dendritic cells are antigen-presenting cells that activate the lymphocytes. Macrophages are phagocytes primarily involved in the innate immune response.

The lymphatic vessels form a network that transports lymph throughout the body.

The lymphoid tissues and organs, such as the spleen and thymus, provide the sites for the activation of lymphocytes.