Britannica Sources used in this answer

How does the lymphatic system help remove pathogens from the body?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Health monitoring — human disease The routine monitoring of blood pressure levels is an important part of assessing an individual's health. Blood pressure provides information about the amount of blood in circulation and about heart function and thus is an important indicator of disease.

The lymphatic system protects the body against infection by acting as both a production site for immune cells and a filtration network for pathogens.123

Immune Cell Production

The system is the primary site for the development, differentiation, and proliferation of lymphocytes—specifically B cells and T cells. These white blood cells are essential for identifying and neutralizing foreign microorganisms.124

Filtration and Destruction

The lymphatic system removes pathogens through the following processes:
* Collection: Lymph collects bacteria and other particulate matter from body tissues and carries them through lymphatic vessels toward lymph nodes.4
* Filtration: As lymph passes through the lymph nodes, bands of lymphoid tissue trap foreign antigens and microorganisms.54
* Immune Response: Within the nodes, macrophages ingest foreign matter, while lymphocytes are activated to proliferate and produce antibodies or directly attack the invaders.54

This filtration process is critical for immune defense, though it can cause lymph nodes to swell during an active infection as they work to eliminate the pathogen.4