ANTIGENS, ANTIBODIES AND THE IMMUNE RESPONSE Essay

ANTIGENS, ANTIBODIES AND THE IMMUNE RESPONSE - Essay Example This essay shall discuss antigens, antibodies, and the immune response, including what can happen when a patient has an immune reaction to a blood transfusion. First and foremost, the skin itself is the body’s first line of defence. The skin defends the body as it makes it impenetrable to organisms (Kauffman, et.al., 2002). The oil and sweat glands of the skin helps prevent the growth of microorganisms; moreover, sweat has lysozymes which then break down bacterial cell walls. Aside from the skin, the digestive and respiratory tracts also have natural defence mechanisms (Raven, 2006). The cells lining these tracts contain bronchi and bronchioles where mucus is secreted and where microorganisms are then trapped. They are then naturally expelled through coughing, sneezing, vomiting, and diarrhoea. The second line of defence of the body is the cellular level line of defence. Such line of defence includes cells of the body which mostly function for the specific management and elimination of microorganisms (Gorbach, et.al., 2003). The macrophages are the large and irregularly shaped cells. They usually eliminate microbes by ingesting them using the process of phagocytosis. In the macrophage, the lysosome is fused with the bacteria and the microbe is then killed with free radicals in significant quantities released (Raven, 2006). Macrophages also consume viruses and dust particles. They are located in the extracellular fluid and their actions support the actions of other parts of the body, mostly the spleen and the bone marrow. The neutrophils are another type of cell which helps fight off microorganisms (Hornef, et.al., 2002). These are leukocytes which ingest and then kill bacteria, also applying the process of phagocytosis. They also release chemicals which kill the bacteria. The natural killer cells do not directly attack the