Lymphatic System Physiology PDF

ANATOMY AND PHYSIOLOGY WITH PATHOPHYSIOLOGY CLINICAL INSTRUCTOR: RAFAEL SIEGFRED B. FONTANILLA, RN. LYMPHATIC SYSTEM also known as “the Body’s sewage system” a subsystem of both the CIRCULATORY SYSTEM and IMMUNE SYSTEM It removes excess fluid from body tissues and returns it to the...

ANATOMY AND PHYSIOLOGY WITH PATHOPHYSIOLOGY CLINICAL INSTRUCTOR: RAFAEL SIEGFRED B. FONTANILLA, RN. LYMPHATIC SYSTEM also known as “the Body’s sewage system” a subsystem of both the CIRCULATORY SYSTEM and IMMUNE SYSTEM It removes excess fluid from body tissues and returns it to the bloodstream it is an one direction, open-ended, network of vessels 3 MAIN DUTIES OF THE LYMPHATIC SYSTEM 1. Contains white blood cells called “ Lymphocytes,” 2 3 which are used to fight infection 3 MAIN DUTIES OF THE LYMPHATIC SYSTEM 2. Acts as a “ one- way drainage 1 system,” 3 transporting fluid from body tissues into the blood circulation. 3 MAIN DUTIES OF THE LYMPHATIC SYSTEM 3. Removes waste products produced by cells. 1 2 PARTS OF THE LYMPHATIC SYSTEM These parts work together to: a. Support the immune system b. Maintain f luid balance, and; c. Filter harmful substances in the body  1. LYMPH a clear fluid that f lows throughout the lymphatic system. I t contains white blood cells I t helps transport nutrients, oxygen, and waste products between the blood and tissues  2. SPLEEN an organ located in the upper left abdomen. I t filters blood, removing damaged blood cells and pathogens ( disease- causing agents). I t also stores platelets and white blood cells, and i t plays a role in immune response.  3. TONSILS Are collections of lymphoid tissue in the throat. Acts as the first line of defense against pathogens that enter the body through the mouth and nose. I t also helps in trapping and destroying bacteria and viruses. TYPES OF TONSILS  4. THYMUS gland located in the thoracic region, posterior to the breastbone. I t is responsible forthe maturationand development of T lymphocytes ( T cells), which are essential to the immune system. 5. LYMPHATIC VESSELS Network of thin tubes Carry lymph throughout the body. They collect excess t issue f luid, f i l ter i t , and return i t to the bloodstream. 6. BONE MARROW Serves as the primarysite for the production and maturation of certain types of immune cells known as “ lymphocytes.” Specifically, B cells and T cells which are critical components of the immune system, which helps the body defend against infections and diseases. 7. LYMPH NODES Small, bean- shaped structures Located along the lymphatic vessels. They f i l ter lymph, removing pathogens, damaged cells, and foreign particles. They also contain immune cells l ike lymphocytes, which f ight infections. Lymph nodes are located in specific areas: When a pathogen is under attack by the lymph node’s lymphocytes, the lymph node may become swollen and painful to the touch. This condition is called lymphadenitis. PHYSIOLOGY OF THE LYMPHATIC SYSTEM FUNCTIONS OF THE LYMPHATIC SYSTEM The lymphatic system helps maintain the fluid balance in the blood. The lymphatic system distributes lymph to wash over tissues (as interstital fluid) to deliver nutrients and remove wastes. The lymphatic system carries absorbed products of lipid digestion. The lymphatic system provides specific immunity against specific pathogens. THREE LINES OF DEFENSE  NONSPECIFIC RESISTANCE VERSUS SPECIFIC IMMUNITY  INFLAMMATION 1.Chemicals (vasodilators) are released by damaged tissues and basophils. The chemicals diffuse across the surrounding tissues and affect any blood vessels in the area. The increased blood flow accounts for the signs of redness and heat, while the increased permeability accounts for the swelling and pain. 2. WBCs stick to the walls of the dilated vessels in the inflamed area (margination). 3. WBCs crwal through the vessel walls (diapedesis) 4. WBCs move to where the concentration of chemicals from damage tissues is the greatest (chemotaxis). 5. WBCs phagocytize foreign material, debris, and pathogens along the way (phagocytosis). ANTIMICROBIAL PROTEINS Interferons are chemicals released by virally infected cells. They do not help the cell that produced them. Instead, interferons encourage surrounding healthy cells to make antiviral proteins so that the virus will not invade them. Interferons also active macrophages and NK cells to fight cancer cells. The complement system includes 20 inactive proteins (always present in the blood) that may be activated bye the presence of a pathogen. Once activated, the proteins initiate one of several different pathways to ensure pathogen destruction through increased inflammation, breaking apart of the pathogen (cytolysis), or coating a pathogenic cell to make it easier for a macrophage to phagocytize it (opsonization) FEVER -A fever is initiated by the production of chemicals (pyrogens) from activated macrophages. These pyrogens travel to the hypothalamus, which the raises the set point for body temperature. The body responds by shivering to produce more heat, whiole the blood vessels in the skin constrict to preserve the heat being generated. Other active attacks This line of defense refers to the functions of leukocytes other than lymphocytes. Neutrophils fight bacteria. Basophils release histamine to promote inflammation. Eosinophils attack worm parasites. Monocytes become macrophages to phagocytize bacteria Specific Immunity ▪ Differs from nonspecific resistance because it requires a prior exposure to a pathogen in order to work. ▪ During the first exposure, the immune system recognizes the specific pathogen as being foreign, reacts to it, and then remembers it. 1. Humoral (Antibody-Mediated) Immunity -involves B cells producing antibodies. 2. Cellular (Cell-Mediated) Immunity involves T cytotoxic cells directly killing cells with foreign antigens.  Forms of Acquired Immunity 1. Active Immunity ▪ Active immunity is when the body’s own immune system mounts an adaptive immune response following direct exposure to a disease organism or antigen. ▪ Active immunity, takes time to develop but is long-lasting as it produces memory lymphocytes that recognize the disease and promptly produce the antibodies needed to fight it.  types of acquired immunity: Natural active immunity Natural active immunity occurs when the body encounters a pathogen during everyday activities, and forms a memory for a faster, stronger response upon re-exposure. Example: catching a cold from a classmate. The body recognizes the virus, activates T cells to destroy infected cells, and retains memory to prevent reinfection by the same virus. Artificial active immunity Occurs when the body acquires a pathogen in an artificial way and then develops its own humoral or cellular immunity. Examples: smallpox, polio, and chicken pox vaccinations.  Forms of Acquired Immunity 2. Passive Immunity ▪ Passive immunity relies on antibodies rather than memory cells. In brief, It involves the introduction of ready-made antibodies to a non-immune individual. ▪ Passive immunity is short-lived (because there are no memory cells) but beneficial where there is a high risk of infection, and the body is unable to develop its own immune response or synthesize its’ own antibodies. Natural passive immunity Natural passive immunity occurs when antibodies are transferred from one individual to another, such as from mother to child through breast milk, providing temporary protection against specific pathogens. An example: breastfeeding. Artificial passive immunity Artificial passive immunity is gained through an injection of antibody-rich serum from another source, like a person, animal, or synthetic production. It provides temporary protection, as the body does not produce its own antibodies. Examples: tetanus, rabies, or snakebite treatment.  IMPORTANCE OF T helper CELLS IN NONSPECIFIC RESISTANCE AND SPECIFIC IMMUNITY T helper cells activate macrophages for nonspecific defense such as inflammation and fever. T helper cells recognize what is foreign and release interleukin-2 to activate B cells in humoralo immunity T helper cells recognize what is foreign and releases interleukin-1 to activate Tcytotoxic cells in cellular immmunity DISEASES AND DISORDERS OF LYMPHATIC SYSTEM Allergies Autoimmune Disorders Elephantiasis Immunodeficiency Disorders Lymphoma Multiple Myeloma Splenomegaly A. ALLERGIES - Hypersensitivities to a foreign antigen. B. AUTOIMMUNE DISORDERS -Disorders that result from the immune system attacking self-antigens. Or healthy cells and tissues Rheumatoid arthritis, Graves’ disease, and myasthenia gravis are examples of some of the autoimmune disorders D. IMMUNODEFICIENCY DISORDERS - Disorders that affect a part of the immune system, resulting in the inability of the immune system to adequately defend the body from pathogens. Congenital immunodeficiency disorders are those that develop Congenital immunodeficiency disorders are those present at birth. These disorders are usually inherited and are very rare. Acquired immunodeficiency disorders are those that develop from a disease or disorder acquired during one’s lifetime. Use of certain prescribed drugs can also cause an individual to develop an acquired immunodeficiency. EXAMPLE: AIDS is an acronym for acquired immune deficiency syndrome. Acquired means that it is not inherited. Immune deficiency means that the immune system fails to provide protection against pathogens. Syndrome refers to the collection of symptoms and signs of disease. Acquired immune deficiency syndrome is the final stage of an HIV (human immunodeficiency virus) infection. C. ELEPHANTIASIS - A tropical disease cause by a roundworm that blocks lymphatic drainage. E. LYMPHOMA - A type of cancer that affects white blood cells and can develop in the organs of the lymphatic system. There are two types of lymphoma: Hodgkin lymphoma and non-Hodgkin F. MULTIPLE MYELOMA - Cancer of the plasma cells in the bone marrow. G. SPLENOMEGALY - An enlargement of the spleen that can be caused by any number of pathological conditions, including anemia, cancers, and certain infections. THANK YOU!