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Overview of the Lymphatic System

By

The Manual's Editorial Staff

Medically Reviewed May 2021 | Modified Sep 2022
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What is the lymphatic system?

The lymphatic system is a network of lymphatic vessels and lymph nodes that carry fluid called lymph. The lymphatic system is part of your immune system Overview of the Immune System The immune system is your body's defense system. It helps protect you from illness and infection. The immune system's job is to attack things that don’t belong in your body, including: Germs... read more , which helps defend against infection and cancer.

Lymph is fluid that oozes out of your tiniest blood vessels. The fluid goes between your cells and brings nourishment and carries away damaged cells, cancer cells, and germs.

Lymphatic vessels are tiny tubes that carry lymph from your tissues to lymph nodes and then from the lymph nodes back into your blood vessels.

Lymph nodes are collection points full of specialized white blood cells White Blood Cells The main components of blood include Plasma Red blood cells White blood cells Platelets read more White Blood Cells that filter out the germs and cells from lymph. These nodes and white blood cells help your body defend against infection and cancer. That's why sometimes an infection or cancer makes nearby lymph nodes swell up Swollen Lymph Nodes Lymph nodes are part of your lymphatic system, which helps fight infection and cancer. Lymph nodes are pea-sized collection points that filter out germs and cells from lymph fluid. Lymph nodes... read more . For example, a throat infection can make lymph nodes in your neck swell up. People call these "swollen glands," but lymph nodes aren't really glands.

You have lymphatic vessels all around your body. Lymph nodes tend to cluster in certain places such as on the side of your neck, under your arms, or in your groin.

Lymphatic System: Helping Defend Against Infection

Lymphatic System: Helping Defend Against Infection

What is the immune system?

  • Germs, such as bacteria, viruses, and fungi

  • Parasites

  • Cancer cells

  • Other things that can get inside your body, such as pollen

The important parts of your immune system include:

  • White blood cells

  • Antibodies

  • The lymphatic system

What can go wrong with the lymphatic system?

The lymphatic system may not work well because of:

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