There are more than 100 lymph nodes or glands along the lymphatic capillaries, especially in the neck, groin and armpit of the body. Each lymph node has a series of fibrous valves, and lymph flows out of these valves, filtering out microorganisms and toxins and destroying them to prevent the spread of infection.
When the virus invades the human body and is infected, the lymph nodes will be swollen and painful. For example, when your throat is inflamed, you will feel two lumps under your chin, which are lymph nodes. After the inflammation disappears, the lymphatic lump will naturally shrink.
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Main functions of lymph nodes
1, filter lymph. Lymph nodes are located in lymphatic reflux channels. When pathogens, foreign bodies and other harmful components invade the superficial connective tissue of the body, these harmful components easily enter the lymphatic capillaries of the whole body with the tissue fluid and return to the lymph nodes with the lymph. With the increase of the volume of lymphatic sinus, the lymphatic flow velocity slows down. When harmful components in lymph flow in the circulation direction, they are in complete contact with macrophages in sinus.
2. Most of them are excised or confined to lymph nodes, effectively preventing harmful components from entering the blood circulation and invading other parts of the body. Participate in the immune response. Lymph nodes play an important role in specific immune responses such as humoral immunity and cellular immunity. Lymphatic reflux can make lymph nodes quickly receive antigen stimulation that invades the body.
3. Lymphatic reflux initiates antigen-specific immune response through a series of complex cellular and humoral factors. Lymph nodes can not only remove antigen components from lymph nodes through immune response, but also trigger immune response in other parts of the body, especially in the parts where harmful components invade, thus reducing the harm to the body in time.
4. Whether the antigen-specific memory cells produced by lymph nodes invade these harmful components again after immune response can be monitored at any time through lymphocyte circulation.
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