THE IMMUNE SYSTEM
Definition of the Immune System
The human immune system is a collective network of tissues, glands, and organs that work in a coordinated effort with each other to guard our bodies from foreign antigens such as viruses, bacteria, and infection causing microorganisms. For the immune system to work properly, two things must happen: first, the body must recognize that it has been invaded, either by pathogens or toxins or by some other threat. Second, the immune response must be activated quickly, before the invaders destroy many body tissue cells. For the immune system to respond effectively, several conditions must be in order, including the proper interaction of non-specific and specific defenses. The nonspecific defenses on the skin do not identify the antigen (a substance able to manipulate an immune response or reaction) that is attacking or potentially attacking the body; instead, these defenses simply react to the presence of what it identifies as something foreign. Often, the nonspecific defenses effectively destroy microorganisms, but if these defenses prove to be ineffective and the microorganisms manage to infect tissues, the specific defenses go into action. The specific defenses function by locating the antigen in question and mounting a response that targets it for destruction. Organs of the Immune System
The organs of our immune system are located all throughout our bodies. The main organs of the immune system are bone marrow, the thymus, the tonsils, the spleen, and the lymph nodes. Bone marrow is the soft tissue that is found inside of most of our bones. Every cell of the human immune system originate from stem cells in the bone marrow. The bone marrow then goes through a process called hematopoiesis, which produces B-lymphocytes (B-cell), immature thymocytes, red blood cells, white blood cells, and platelets. Hematopoiesis is the process wherein hematopoietic stem cells (HSC) differentiate into either lymphoid or myeloid progenitor cells under the influence of growth factors and cytokines produced in hematopoietic tissues. The aforementioned specialized cells all play vital roles in targeting and wiping out foreign antigens.
The thymus is an organ that is found in the upper anterior section of the chest cavity just behind the breastbone. The main function of the thymus, is to produce mature T-lymphocytes, or T-cells. The T-cells play a very important role in the immune system. It is composed of two types of tissues: cortical and medullary. The cortical tissue is an area of intense T-cell development activity. It is where the T-cells develop their antigen receptors. Loss of the thymus, or T-cells, at an early age of life via surgical process or genetic mutation, can result in a severe deficiency of the immune system. The medullary tissue serves as a staging area where T-cells migrate before they are released into the bloodstream.
The tonsils are gland-like structures on the sides of the throat that carry lymph (the fluid that covers the cells in water and nutrients). Their main function is to help your immune system by catching bacteria and viruses that are passing through your throat. The tonsils located at the back of the throat and under the tongue, contain large numbers of lymphocytes and filter out potentially harmful bacteria that might enter the body via the nose and mouth. Unfortunately, sometimes tonsils don’t perform their job very well, and they can often become a hindrance on your health. Treatment for infected tonsils depends on the severity of the infection. In case of acute or mild tonsil infection, one can find relief by practicing some remedies at home, but the course of treatment for chronic tonsillitis can only be decided after thorough physical examination with a sensitivity test. The health care provider examines the inflammation, enlargement and severity of the infected tonsils and decides the basic path of medication. In case of chronic tonsillitis, a...
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