Lymphatic System

1
Lymphatic System

• Lymph vessels or lymphatics
• Lymph nodes
• Lymph
• Lacteals
• Lymphatic capillaries
• Collecting vessels
• Trunks
• ducts
• What is the role of the lymph vessels and nodes?
• Return water and protein containing interstitial
  fluid to the bloodstream.

2
(No Transcript)
3
Lymph

• Lymphocytes
• Macrophages
• Immune role
• Lymphoid organs
• Spleen
• Thymus gland
• Lymph nodes

• Lymph nodes
• Act as lymph filters
• Activate immune cells
• Inflammed lymph nodes
• Buboes
• Black death
• Cancer
• metastasis

4
Lymphoid Organs

• Spleen
• Removes aged and defective blood cells
• Removes bacteria, viruses, and toxins
• Stores blood platelets
• Site of lymphocyte proliferation and immune
  surveillance.
• Splenectomy
• Regeneration in those under 12.

• Tonsils
• Remove pathogens entering the pharynx in air or
  food.
• Peyers patches
• Walls of small intestine
• Appendix
• Destroy bacteria
• Generate memory lymphocytes

5
Immune System

• Role
• Nonspecific Immunity
• Skin
• Barrier
• Secretions (acidic and antibacterial)
• Natural killer cells
• perforin
• Inflammation
• Histamine prostaglandins
• Complement
• Interferon
• Stomach acid
• Saliva (lysozyme)
• Mucous membranes

• Specific Immunity
• Antigen
• Antigenic determinants (specific parts of an
  antigen)
• Antibodies
• Plasma cells
• B-lymphocytes
• T-lymphocytes
• macrophages

6
Antibody Mediated or Humoral Immunity

• Macrophage engulfs a pathogen and displays its
  antigens on its cell membrane. (antigen
  presentation)
• Dendritic cell (connective tissue), Langerhans
  cells (skin), and some B lymphocytes also perform
  this function.
• B lymphocytes specific for that antigen recognize
  the antigen and transform into plasma cells.
• Clonal selection

• Plasma cells make antibodies specifically
  designed for the antigen.
• These proteins bind to the pathogens and mark
  them for death.
• Macrophages engulf and destroy them.
• Role of Helper T cells
• cytokines
• After the pathogens are destroyed, memory B cells
  are left behind.

7
(No Transcript)
8
(No Transcript)
9
Cell-Mediated Immunity

• Used to destroy infected cells.
• Viral or intracelluar bacterial infections
• Cytotoxic T cells
• perforins
• Helper T cells
• Suppressor T cells
• Memory T cells
• Thymus gland

10
More on Immunity

• Natural active immunity
• Natural passive immunity
• Artificial active immunity
• Artificial passive immunity

• Immunizations
• Vaccination
• Primary Immune Response
• Secondary Immune Response

11
(No Transcript)
12
Other Immune Characteristics

• SCIDS
• AIDS (1981)
• Pneumocystis pneumonia
• Kaposis sarcoma
• Dementia
• HIV
• Helper T cells
• Grafts
• Autograftself
• Allograftssame species
• Isograftidentical twin
• Xenograftsdifferent species
• Importance of MHC similarties
• Cytotoxic T cells
• Immunosuppression
• Antibiotics

• Vaccines
• How do they work?
• Attenuated Vaccines
• Dead virus vaccines
• Monoclonal antibodies
• Diagnosis
• Treatment of diseases

13
Autoimmune Diseases

• 5 of North American population is affected.
• Multiple sclerosis
• Graves diseaseexcess Thyroxine.
• Type I diabetes mellitus
• LupusAffects the kidneys, heart, lungs, and skin

• Glomerulonephritis
• Rheumatoid arthritis
• Thalidomide
• Causes
• Foreign antigens are similar to self antigens
• New self antigens
• Mutation or infections

14
Hypersensitivities

• Histamine flood is released
• Cause local and systemic inflammation
• Runny nose
• Watery eyes
• Hives
• Asthma
• GI discomfort
• Anaphylactic Shock
• Allergen directly enters the blood.
• Bronchioles constrict
• Sudden, extreme vasodilation and fluid loss.
• Epinephrine is used as a treatment.

• Immune system causes tissue damage as it fights
  off a perceived danger.
• Allergen
• Immediate Hypersensitivities
• Begin within seconds after contact
• Anaphylaxis
• IgE antibodies are produced in large numbers
• Problems occur on the second exposure

15
Hypersensitivities

• Delayed Hypersensitivities
• 1-3 after exposure
• Involve cytotoxic T cells
• Allergic contact dermatitis (poison ivy, heavy
  metal exposure)