1. The Lymphatic and Immune Systems

2. The Lymphatic and Immune Systems
Main structures of the lymphatic system
Lymphatic vessels
Main components of the immune system
Lymphocytes
Lymphoid tissue
Lymphoid organs

3. The Lymphatic System
Lymphatic vessels collect tissue fluid from loose connective tissue
Carry fluid to great veins in the neck
Fluid flows only toward the heart
Figure 20.1

4. Functions of Lymphatic Vessels
Collect excess tissue fluid and blood proteins
Return tissue fluid and blood proteins to bloodstream

5. Orders of Lymphatic Vessels
Lymph capillaries
- smallest lymph vessels
first to receive lymph
Lymphatic collecting vessels
collect from lymph capillaries

6. Orders of Lymphatic Vessels
Lymph nodes
scattered along collecting vessels
Lymph trunks
collect lymph from collecting vessels
Lymph ducts
empty into veins of the neck

7. Lymphatic Capillaries
Located near blood capillaries
Receive tissue fluid from Connective Tissue
- increased volume of tissue fluid
- minivalve flaps open and allow fluid to enter
Highly permeability allows entrance of
tissue fluid
bacteria, viruses, and cancer cells

8. Lymphatic Capillaries
Lacteals
– specialized lymphatic capillaries
- located in the villi of the small intestines
- receive digested fats
- fatty lymph – chyle

9. Lymphatic Capillaries
Figure 20.2a, b

10. Lymphatic Collecting Vessels
Accompany blood vessels
Composed of the same three tunics as BVs
Contain more valves than veins do
helps direct the flow of blood
Lymph propelled by
bulging of skeletal muscles
pulsing of nearby arteries
tunica media of the lymph vessels

11. Lymph Nodes Cleanse the lymph of pathogens
Human body contains around 500
Lymph nodes are organized in clusters

12. Lymph Nodes
Figure 20.3

13. Microscopic Anatomy of a Lymph Node
Fibrous capsule – surrounds lymph nodes
Trabeculae – connective tissue strands
Lymph vessels
Afferent lymphatic vessels
Efferent lymphatic vessels

14. Lymph Node Microscopic Anatomy
Figure 20.4a

15. Lymph Trunks Lymphatic collecting vessels converge
Five major lymph trunks:
Lumbar trunks - receives lymph from lower limbs
Intestinal trunk - receives chyle, digestive organs
Bronchomediastinal trunks - collects lymph from thoracic viscera
Subclavian trunks - receive lymph from upper limbs and thoracic wall
Jugular trunks - drain lymph from head & neck

16. Lymph Nodes, Trunks, and Ducts
Figure 20.3

17. The Lymphatic Trunks
Figure 20.6a

18. Lymph Ducts Cisterna chyli Thoracic duct Right lymphatic duct
located at the union of lumbar and intestinal trunks
Thoracic duct
Ascends along vertebral bodies
Empties into venous circulation
Junction of left internal jugular and left subclavian veins
Drains three quarters of the body
Right lymphatic duct
empties into right internal jugular and subclavian veins

19. Palpation

20. Mononucleosis (aka Mono or ‘the kissing disease’)
What is it?
Mononucleosis is a viral infection causing fever, sore throat, and swollen lymph glands, especially in the neck.

21. Mono
Mononucleosis, or mono, is often spread by saliva and close contact. It is known as "the kissing disease," and occurs most often in those age 15 to 17. However, the infection may develop at any age.

22. Mono
Mono is usually linked to the Epstein-Barr virus (EBV), but can also be caused by other organisms such as cytomegalovirus (CMV).

23. Mono
Blood work often reveals a higher-than-normal white blood cell (WBC) count and unusual-looking white blood cells called atypical lymphocytes, which are seen when blood is examined under a microscope. Atypical lymphocytes and abnormal liver function tests are a hallmark sign of the disease.
A monospot test will be positive for infectious mononucleosis.

24. To relieve typical symptoms:
Drink plenty of fluids.
Gargle with warm salt water to ease a sore throat.
Get plenty of rest.
Take acetaminophen or ibuprofen for pain and fever.
You should also avoid contact sports while the spleen is swollen (to prevent it from rupturing).

25. The Immune System Recognizes specific foreign molecules
Destroys pathogens effectively
Key cells – lymphocytes
Also includes lymphoid tissue and lymphoid organs

26. Lymphocytes Infectious organisms attacked by inflammatory response
macrophages, then lymphocytes
Cytotoxic T lymphocytes
Attack foreign cells directly
Binds to antigen-bearing cells
Perforates cell membrane
Signals cell to undergo apoptosis

27. Lymphocytes B lymphocytes - become plasma cells
- secrete antibodies, mark cells for destruction by macrophages

28. Figure 20.7

29. Lymphocyte Activation
Lymphocytes originate in bone marrow
T lymphocytes travel to the thymus gland
B lymphocytes stay in bone marrow
Able to recognize a unique antigen
Gain immunocompetence
travels through blood stream
meets and binds to a specific antigen

30. Lymphocyte Activation
Activating T or B cells produce
Effector lymphocytes
Short-lived, attack immediately
Memory lymphocytes
Wait until body encounters their antigen again
Basis of acquired immunity
Guard against subsequent infections

31. Figure 20.8

32. Lymphoid Tissue Most important tissue of the immune system
Two general locations:
Mucous membranes of digestive, urinary, respiratory, and reproductive tracts
- Mucosa-associated lymphoid tissue (MALT)
Lymphoid organs (except thymus)

33. Lymphoid Organs Primary lymphoid organs Secondary lymphoid organs
Bone marrow
Thymus
Secondary lymphoid organs
Lymph nodes, spleen, tonsils
Aggregated lymphoid nodules
Appendix

34. Lymphoid Organs Designed to gather, destroy infectious microorganisms
Figure 20.10

35. Thymus Immature lymphocytes develop into T lymphocytes
- secretes thymic hormones
- most active in childhood
Functional tissue atrophies with age
- composed of cortex and medulla
- medulla contains Hassall’s corpuscles (thymic corpuscles)
Differs from other lymphoid organs
- functions strictly in lymphocyte maturation
- arises from epithelial tissue

36. Thymus
Figure 20.11

37. Lymph Nodes Functional pathway Lymph percolates through lymph sinuses
Most antigenic challenges occur in lymph nodes
Antigens destroyed – activate B and T lymphocytes

38. Spleen Largest lymphoid organ Two main blood-cleansing functions
Removal of blood-borne antigens
Removal and destruction of old or defective blood cells
Site of hematopoiesis in the fetus

39. Spleen Destruction of antigens
Site of B cell maturation into plasma cells
Phagocytosis of bacteria and worn-out RBCs, WBCs and platelets
Storage of platelets

40. White pulp – thick sleeves of lymphoid tissue
Red pulp - surrounds white pulp
- composed of venous sinuses
- splenic cords

41. Spleen
Figure 20.12

42. Tonsils Simplest lymphoid organs Four groups of tonsils
palatine, lingual, pharyngeal, and tubal tonsils
Arranged in a ring to gather and remove pathogens
Underlying lamina propria consists of MALT

43. Palatine Tonsil
Figure 20.13

45. Aggregated Lymphoid Nodules and Appendix
MALT – abundant in walls of intestines
Fight invading bacteria
Generate a wide variety of memory lymphocytes
- aggregated lymphoid nodules (Peyer’s patches)
- located in the distal part of the small intestine
Appendix – tubular offshoot of the cecum

46. Aggregated Lymphoid Nodule
Figure 20.14

47. Lymphoma Neoplasm (tumor/abnormal growth) in the lymph tissue.
Two types: Hodgkin’s disease or non-Hodgkin’s disease.

48. Hodgkin’s Disease
Malignant lymphoma which has been linked to viral infections such as EBV (Epstein-Barr virus {mono}), HIV, and exposure to wood and wood products.
Most often occurs in young adults.
Most common symptom is painless, swelling of the lymph nodes in the neck, armpit, or groin. Other symptoms include fatigue, unexplained fever, night sweats, and indigestion.

49. Hodgkin’s Disease Diagnosis Often shows up on a CAT scan.
Confirmed by biopsy.
Treatment usually includes chemotherapy and radiation.

50. Non-Hodgkin’s Lymphoma
Patients with HIV/AIDS or those who have received immune suppressive therapy are at higher risk for developing non-Hodkin’s lymphoma.
Same presenting symptoms as Hodgkin’s and treatment is similar.

51. Chemotherapy
Works by killing fast-growing cancer cells. Unfortunately, chemo can't always tell the difference between cancer cells and fast-growing healthy cells, including RBCs and WBCs.

52. Chemotherapy
Nurses will wear special gloves and gowns when preparing and giving you chemotherapy drugs. Additionally, pharmacists prepare the drugs in areas with special ventilation systems. Special procedures are used for disposing of materials after mixing and administrating the drugs. There are separate plastic containers to dispose of sharp items, syringes, IV tubing and medication bags.

53. Radiation
 Cancer treatment that uses high doses of radiation to kill cancer cells and stop them from spreading. 

54. Immunity
The ability of the body to defend itself against infectious agents, foreign cells, and even abnormal body cells, such as cancer.
Immunity can be acquired, like when you get chicken pox and then you are protected from getting it again.
Immunity can be artificially acquired like when you get a vaccination.

55. Nonspecific Immunity Innate-you are born with it.
Provides immediate and general protection against invaders.

56. Nonspecific Immunity Physical and chemical barriers:
Intact skin is a physical barrier
Skin also produces chemical barriers to infection (sweat, tears, oil) .
Mucus membranes produce mucus which trap foreign material and form a barrier to invaders.
Cilia sweep out debris and impurities.

57. Nonspecific Immunity
Phagocytosis: Leukocytes (WBC) can destroy infectious agents “cell eating.”
Natural Killer Cells: Type of WBC that recognizes body cells with abnormal membranes. Cell membranes can become altered from cells being infected with foreign invaders like viruses.

58. Nonspecific Immunity
Fever: When phagocytes destroy invaders, they release a substance that raises the body temperature. Fever aids the immune system by stimulating phagocytosis, increasing metabolism.

59. Nonspecific Immunity
Interferon: Group of substances that boost the immune system.
First found in flu cells infected with the flu virus and was named for its ability to interfere with viral multiplication.
Virus-infected cells and other agents produce interferon.

60. Nonspecific Immunity Inflammation
1500 B.C. Egyptians used dried myrtle to relieve back pain. In 200 B.C. Hipprocrates prescribed willow tree bark to relieve fever and pain. Today the active ingredient in aspirin, acetylsalicylic acid, is derived from a related anti-inflammatory chemical (salicylic acid) found in myrtle leaves and willow tree bark.

61. Nonspecific Immunity Inflammation:
The signs and symptoms of inflammation are redness, swelling, heat, and pain.
Protective tissue response to injury or invaders. Blood vessels dilate to increase blood flow (hyperemia) to the area. That causes the heat and redness.

62. Inflammation

64. Nonspecific Immunity
Inflammation: As blood flow increases, more leukocytes reach the area. The damaged tissue releases a substance called histamine that causes the capillary walls to become more permeable (“leaky”). This increased permeability enables plasma and leukocytes to move out of the blood vessels and into the tissues (exudate). This is what causes pain (exudate pressure on the nerve endings) and swelling.

65. Nonspecific Immunity
Inflammation: Bacterial infections may cause inflammation. The toxin-producing bacteria triggers an inflammatory response. The bone marrow and lymph nodes release large quantities of leukocytes. So an increase in a WBC (white blood cell count) can indicate a inflammatory response.

66. Specific Immunity
Acquired-protects against particular identified foreign agent and develops in response to that agent.
Once established against a foreign agent, specific immunity is able to respond to future exposures to that same agent.

67. Specific Immunity
Specific immunity or the immune system is connected to the body via the lymphatic system.
Specific immunity is based on the ability to recognize and respond to foreign elements that triggers the immune response (anitgens).
The specificity of acquired immunity is its ability to recognize these different antigens.

68. Specific Immunity
Specific immunity against antigens includes humoral and cell-mediated immunity.
Humoral includes antibodies. (B cells)
Cell-mediated includes activated lymphocytes. (T cells)
Acquired immunity includes both antibodies and activated lymphocytes.

69. Cell Mediated-Immunity(T cells)
T lymphocytes (several types): *Cytotoxic (CD8)-”Killers”-release poison into ‘bad’ cell. Important in killing cells that have been invaded by virus. Also can destroy cancer cells. *Helper (CD4)-Boost, stimulate other cells. *Memory-rapid mobilization to repeat offender *Suppressor-dampen immune response.

70. Humoral Immunity (B cells)
Plasma cells (Immunoglobulins) IgG-neutralizes toxins, bacteria, viruses IgM-protects newborns IgA-localized protection at mucosal surface IgE-Allergy IgD-Activates B lymphocytes Memory cells

73. Viral Infection

74. Bacterial Infection

75. Hypersensitivity (Allergies)
Some diseases result from an individual’s immune response, which causes tissue damage and destruction rather than immunity. The immune phenomena are destructive rather than defensive in an individual who is hypersensitive or allergic to an antibody.
Can be local (like a welt) or systemic (like anaphylaxis).

76. Hypersensitivity (Allergies)
Abnormal sensitivity to allergens result in the overproduction of IgE.
IgE (immoglobulin from B cells) attaches one end to a cells called basophils and mast cells; its other end points away, where IgE can bind to the allergens.
When allergens enter the body and bind to the IgE antibodies, the cells break down and release chemicals.

77. Hypersensitivity Histamine is one of the chemicals released.
Histamine causes dilation of the blood vessels, making them leak plasma into the tissues. This tissue fluid causes edema (swelling). Examples: nasal congestion, welts, hives.
Treatment would include anti-histamine medications.

78. Hives

79. Hypersensitivity
Anaphylaxis is systemic reaction which follows the same underlying cellular mechanisms of a local reaction but on a ‘global’ scale. The cell permeability is body wide causing low blood pressure (hypotension) and shock. Smooth muscle contraction in the airway may cause respiratory distress.
Epinephrine, glucocorticoids, or cortisone are used to reduce the immune response.

81. Autoimmunity
The immune system response normally recognizes the difference between the individual’s own tissues and those of invaders; this is known as tolerance.
When tolerance fails, an autoimmune disease is the result.
Autoimmunity occurs when individuals develop antibodies (called autoanitbodies) to their own tissues or self-anitgens.

82. Lupus Chronic inflammatory disease. It is an autoimmune disease.
90% are women.
Affects many different body systems including joints, skin, kidneys, blood cells, heart, and lungs.
Causes: Exact cause is unknown. Likely due to a combination of factors including genetics and exposure to a certain unknown trigger.

83. Lupus
Signs and Symptoms: extreme fatigue, headaches, painful or swollen joints, fever, anemia, edema, pleurisy, butterfly-shaped rash across cheeks and nose, sun- or light-sensitivity (photosensitivity), hair loss, abnormal blood clotting, fingers turning white and/or blue when cold (Raynaud’s phenomenon), mouth or nose ulcers…. ALMOST EVERY SYMPTOM IN OTHER WORDS!!!!!

84. Lupus With all those symptoms, how do you diagnosis Lupus?
It’s hard. Lupus is known as “the great imitator,” because its symptoms mimic so many other illnesses. The doctor will look for signs of inflammation, your lab results, medical history, and family history. Test results can suggest Lupus, but may be positive or negative depending upon inflammation at the time.

85. Lupus
How is it treated?
-Corticosteroids (prednisone, methylprednisolone, hydrocortisone)
-Monoclonal antibodies
-Aspirin
People with lupus are generally treated by a rheumatologist (specializes in diseases of the joints and muscles).

86. Lupus
Prognosis: There is no cure for lupus, and some people do die. However, people with non-organ threatening aspects of lupus can look forward to a normal life-span if they follow their treatment plan.

87. Lupus

89. Immune Deficiency
AIDS (acquired immunodeficiency syndrome) destroys the individual’s immune system. This makes a person remarkably susceptible to infection.
What causes it? It is caused my the human immunodeficiency virus (HIV). HIV is a retrovirus; that is, it carries its genetic information as RNA rather than DNA.

90. AIDS
The virus (HIV) infects primarily helper or CD4 lymphocytes. The virus replicates within the lymphocytes, killing them and spreading them to others. The lymphocytes normally activate B-lymphocytes; so this basically cripples the body’s immune system. The body then is more susceptible to infections and tumors that could easily be controlled by a healthy immune system.

91. AIDS
How do I get it? It is transmitted via contaminated body fluids, including blood, semen, vaginal secretions, and breast milk. It can be transmitted by unprotected anal, oral, or vaginal intercourse; birth; breast feeding; and the sharing of needles.

92. AIDS

93. AIDS
Many people don’t develop signs or symptoms immediately after HIV infection. The length of the asymptomatic period may last from months to many years. The long latency period increases the risk of spreading the disease because the infected person is unaware they have it.

94. AIDS
The virus continues multiplying, infecting and killing CD4 lymphocytes. Once the immune symptom is weakened enough the person will develop signs and systems. Eventually, a threshold is crossed a person moves from being HIV-infected to having AIDS. (CD4 count less that 200).

95. AIDS How is it diagnosed?
HIV anitibodies are detected with the enzyme-linked immunosorbent assay (ELISA).
AIDS is usually diagnosed by CD4 count less than Healthy people have CD4 count of 1000.

97. AIDS Opportunists
Kaposi's sarcoma is a type of cancer that mainly affects the skin, mouth, and lymph nodes.  
Due to weakened immune systems, people with HIV are more likely to develop certain cancers.

98. AIDS Opportunists
Candidiasis (Thrush) is a fungal infection of the mouth, throat, or vagina. CD4 cell range: can occur even with fairly high CD4 cells.
Cytomegalovirus (CMV) is a viral infection that causes eye disease that can lead to blindness.CD4 cell range: under 50.

99. Thrush (Candidiasis)

100. AIDS Opportunists
Herpes simplex viruses can cause oral herpes (cold sores) or genital herpes. These are fairly common infections, but if you have HIV, the outbreaks can be much more frequent and more severe. They can occur at any CD4 cell count.

101. Herpes Simplex Virus

102. AIDS Opportunists
Pneumocystis pneumonia (PCP) is a fungal infection that can cause a fatal pneumonia. CD4 cell range: under 200. Unfortunately this is still a fairly common in people who have not been tested or treated for HIV.

103. PCP Pnuemonia

104. AIDS
How is it treated? Drug treatment started shortly after infection increases the chances the immune system will not be destroyed by HIV. There is no cure for AIDS, but anti-HIV medications are used to control the replication of the virus and progression of the disease.

105. AIDS Medication
Highly active antiretroviral therapy (HAART)-combines three or more anti-HIV medications in a daily regimen. Target HIV replication and entry. (Altripla, Travada, Vreead, etc)

106. Comfort Care/Hospice
Comfort care is usually terminally ill and have DNRs; we provided hydration (PO/IV), pain medication, O2 therapy, medications that pt can tolerate taking. In other words, do what you can to make them comfortable until they pass.

107. Vaccinations Provides artificial immunity.
Two types: Active and Passive.
Active: Person forms anitbodies (given a weakened or attenuated organism or deactivated organism).

108. Vaccinations
Passive: What happens when a person is exposed to a serious disease like hepatitis, tetanus, or rabies and has no immunity built up?
It would take too long to build up antibodies in response to the disease, so the person is given passive immunity……doses of preformed antibodies (usually from a horse) are given to the person. Breast milk is considered passive.