Transcript Lymphatic system - davis.k12.ut.us

Lymph & Immunity
Endocrine System
Ch 7 & 15
Objectives
• Diagram and label organs of the lymphatic, immune, and endocrine
systems.
• Describe the function of the organs in the lymphatic, immune, and
endocrine systems.
• Describe some tissues in the lymphatic, immune, and endocrine
systems.
Lymphatic system
• Consists of vessels and organs.
• Lymphatic capillaries absorb excess tissue fluid and return it to the
bloodstream.
• Lymphatic capillaries in the small intestines called lacteals absorb fats
(lipoproteins) and send them to the blood stream.
• Lymphatic organs make, maintain, and distribute lymphocytes.
• Lymphatic system helps defend the body against pathogens.
Cells of Lymphatic system- made in bone
marrow
• Macrophages-phagocytic, eat up cancer cells that don’t have the body’s antigens.
Present pathogen antigens to T cells.
• Neutrophils- Phagocytic, Most abundant white blood cell, produce antibodies
that fight microbes, last 5-90 hours.
• Eosinophils- allergic response, fight parasites, fight viruses by breaking up RNA.
• Basophils- allergic response, phagocytic, store histamine, may regulate T cells
• Dendritic cell- in skin, nose, lungs; controls the immune response, present
antigens to T cells so they can kill pathogens.
• B cell- Made in bone marrow, mature in thymus. memory, tagger, identifier/spy
• T cell- killer, helper, memory
• Lymph nodes are where B and T cells and Dendritic cells get coordinated in their
immune response.
Lymphatic system
Tonsils
Lymphatic organs
• Tonsils- nodules surrounded by a
capsule ring around the pharynx. First
line of defense against pathogens that
enter the mouth.
Function of Lymphatic vessels
• Have valves that keep fluid moving in one direction.
Lymphatic organs
• Red bone marrow- produces all blood cells. (Red and white blood
cells)- Adults- sternum, vertebrae, ribs, pelvis, upper ends of humerus
and femur. Children have bone marrow in most bones.
• B cells- mature in bone marrow
• T cells- mature in the Thymus near the heart
Lymphatic system organs
• Thymus gland- in thoracic cavity anterior to heart, between the
trachea and sternum. It is smaller in an adult than in a child. It is like
the Basic Training Barracks for Soldiers.
• Produces hormones (thymosin) helps T cells mature
• Help T cells mature. 5% leave the thymus.
• If they react with body cells they die in the thymus.
• If they can kill pathogens they leave the thymus.
Lymph organs
• Spleen- filters blood. Largest lymph organ. Upper left abdominal
cavity posterior to stomach.
• Red pulp- cavities containing macrophages filter pathogens and old red blood
cells from veins
• White pulp- ? function
Lymphatic system organs
• Lymph nodes- along lymph vessels, in sinuses. Filter lymph.
Macrophages engulf pathogens, cancer cells, and debris.
Lymphatic organs
• Peyer’s Patches- segments of intestine and appendix that contain
lymphocytes that fight infection.
Disorders of the Lymphatic system
Lupus
Anti-DNA antibodies
Disorders
• Rheumatoid arthritis- T and B cells break down joint proteins.
Disorders
• Myasthenia gravis- antibodies attach to and stop neuromuscular
junctions.
• Multiple sclerosis- T cells attack myelin sheath in nerve fibers.
Immune cells & Chemical defenses
• Chemical defense
• Lysozyme- enzyme that is anti-bacterial
• Perspiration, Saliva, Tears
• Acid of stomachdoesn’t kill Helicobacter pylori that causes ulcers
• Acid level in vagina
• Antigens- proteins that attach to pathogens.
• B cell lymphocytes-recognize specific antigens
• T cell lymphocytes-recognize specific antigens
Antibodies-fit on antigen to neutralize it
B cells
• Have plasma proteins that produce antibodies
which bind to specific antigens.
• They then secrete cytokines (small signaling
proteins) which start cloning
• Each lymphocyte has only one type of receptor
that fit with an antigen like a lock and key.
Clumps of antibody/antigen attract white
blood cells
B cells
• Produce plasma cells that float in the blood and produce antibodies in
the blood using rough endoplasmic reticulum.
• Some B cells maintain the memory of the antigen so they can quickly
make antibodies if the body encounters a specific pathogen.
Plasma cells
• Produce about 2 million different protein antibodies
• Antibodies:
• IgG crosses the placenta to new baby, Helps White blood cells bind to
invaders. (Temporary immunity)
• IgM first antibody formed by a new infection. Clumps cells
• IgA antibody found in saliva and milk. Prevents pathogen from binding to
epithelial cells in lungs and digestive system.
• IgD antibody on growing B cells tells when they are mature.
• IgE antibody on basophils and mast cells. Allergic reactions.
T cells
• Kill viruses, cancer cells
• Helper T cells regulate
immunity
• Need a macrophage to help
them identify the pathogen.
• Memory T cells will
remember the antibody and
kill the pathogen in the
future.
T cell function
• Macrophages go to spleen after eating a
pathogen and present part of the broken down
pathogen in a lysosome (antigen) to the T cell
• There are 50+ human leukocyte antigens, that
identify the cell as itself.
• Make it difficult to transplant tissues from one
person to the next.
• T cells will destroy non-self cells that don’t carry
these 50 antigens.
• Some T cells have vacuoles with enzymes that
punch holes in virus infected cells and cause
apoptosis of the cell.
Immune system cells
Inflammation
• Neutrophils and Macrophages surround and kill pathogens
• Red, Heat, Swelling, Pain
• Histamine released by damaged cells and mast cells cause capillaries to dilate.
Increases blood flow.
• Complement proteins (C proteins) bind to mast cells and release histamine.
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• Other Complement proteins make holes in bacteria
• Interferon proteins warn non-infected cells there is a virus and prepare to disable virus
reproduction. (Hepatitis C)
White blood cells arrive to phagocytize pathogens and debris
Neutrophils die off and become pus.
Nearby cells secrete chemicals that repair and grow new tissue.
If neutrophils are overwhelmed, they’ll secrete cytokines which attract more white
blood cells, like monocytes, which turn into Macrophages and enlist lymphocytes to
kill specific pathogens.
Inflammatory response
Vaccines
• Disabled virus or bacteria that the body uses to make memory B cells.
• After a few days antibodies are no longer produced, so a second
booster shot gives a larger reaction than a first initial shot.
Gamma globulin
• Proteins that provide temporary immunity, because they aren’t
produced by the body’s B cells.
• Found in mother’s milk.
Monoclonal antibodies
• Proteins that bind to specific antigens.
• Produced by B cells.
• Diagnose pregnancy, flu, aids virus, respiratory virus.
• Human chorionic gonadotropin hormone is present in the urine of a pregnant woman.
• Antibodies bind to this hormone and produce a chemical color change in a test strip.
Immunity
• Vaccine- presents an inactive virus so the body can build antibodies
against the invader. Builds memory B and T cells. (Wanted poster)
• Antibodies- passive, can disable a pathogen by binding to the cell
wall/membrane/protein coat
• Transfer factors from mother or animal factories- Helps B cells identify
pathogen (Wanted posters from parent or other organism)
• Get sick from pathogen, build antibodies using B & T Cell memory.
HIV
• Virus attacks helper T cells, which help fight pathogens.
• The person is left with no immune defense.
Immune system videos
• https://www.youtube.com/watch?v=3UAo6V6EgoU
• HIV: https://www.youtube.com/watch?v=odRyv7V8LAE
• T Cells: https://www.youtube.com/watch?v=mzQy0CqjtNY
• Immune cartoon: https://www.youtube.com/watch?v=iVMIZy-Y3f8
• https://www.youtube.com/watch?v=zQGOcOUBi6s
• Measles https://www.youtube.com/watch?v=y0opgc1WoS4