How does nose cilia fight pathogens to protect the body?
1. Filtration and Trapping: The nasal passages are lined with mucus-producing cells and tiny hair-like projections called cilia. The mucus secreted by these cells acts as a sticky barrier that traps dust, pollen, bacteria, viruses, and other particles that enter the nose during inhalation. The cilia, which are constantly moving in a wave-like motion, help to move the trapped particles and mucus towards the back of the throat.
2. Physical Barrier: The cilia themselves form a physical barrier that prevents pathogens from reaching the deeper parts of the respiratory system, including the lungs. The constant movement of the cilia helps to sweep away pathogens and prevent their colonization in the nose.
3. Immunoglobulin Coating: The mucus lining of the nasal passages contains immunoglobulins, which are antibodies that can recognize and bind to specific pathogens. The cilia help to distribute these immunoglobulins throughout the mucus, enhancing the immune response against invading microorganisms.
4. Mucociliary Clearance: The coordinated movement of cilia and mucus is known as mucociliary clearance. This mechanism helps to clear away trapped pathogens, dust, and debris from the nasal passages. The mucus, carrying the captured particles, is either expelled through the nose by sneezing or swallowing or directed to the back of the throat, where it is either swallowed or coughed up.
5. Activation of Immune Response: Cilia also play a role in initiating an immune response when they come into contact with pathogens. Certain receptors on the cilia can detect and bind to specific molecular patterns associated with bacteria and viruses. This interaction triggers the release of chemical signals that activate immune cells, such as neutrophils and macrophages, to engulf and destroy the invading pathogens.
Overall, nose cilia act as a first line of defense against pathogens by physically blocking their entry, trapping them in mucus, facilitating their removal through mucociliary clearance, and activating the immune response. By working together with other immune mechanisms in the respiratory system, nose cilia help to protect the body from infections and maintain respiratory health.