IMMUNE SYSTEM 3 Flashcards
Symptoms of the lymphatic system
Lymphoedema—
• Lymphangitis—
• Elephantiasis—
Lymphoedema
swelling (oedema) of tissues caused by blockage of lymph
vessels
• Lymphangitis
inflammation of lymph vessels, may progress to septicaemia
blood infection
• Elephantiasis
severe lymphoedema of limbs resulting from parasite infestation
of lymph vessels (can be reversible with medication when acute, but after time,
blockage becomes chronic and can not be reversed)
Tonsils lymphatic system
• Composed of three masses of lymphoid tissue around the openings of the mouth
and throat
• Palatine tonsils (“the tonsils”)
• Pharyngeal tonsils (adenoids)
• Lingual tonsils
• Subject to chronic infection
• Enlargement of pharyngeal tonsils may impair breathing
Spleen lymphatic system
Largest lymphoid organ in body
• Located in upper left quadrant of abdomen
• Often injured by trauma to abdomen
• Surgical removal called splenectomy
• Functions include phagocytosis of bacteria
and old RBC’s; acts as a blood reservoir
Splenomegaly—
enlargement of the spleen
When an antigen enters your body, it:
ü first produces mucous which tries to flush it out and stop more from entering the body
ü then sends WBC’s to surround the virus
ü produces special cells called antibodies that lock on and destroy the virus
Vaccines
produce an immune response in the body without causing illness by using dead or severely
weakened (attenuated) viruses to trick the cells into believing you’ve had the disease. So, when given a
vaccine, your immune system responds to these weakened ‘invaders’ and creates antibodies to protect you
against future infection. It has special ‘memory’ cells that remember and recognise specific germs or viruses.
• Then, when you are exposed to the live virus again, the circulating antibodies fight against the antigens to
destroy them.
• Sometimes you will still have signs and symptoms of the illness, but it should be a less serious form of the
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Artificial active immunity - types of vaccine
(i) Vaccine containing dead pathogens. Antigen is still recognised and an immune response made
• Salk polio vaccine (IV Polio vaccine)
• Influenza
• Whooping cough
(ii) Vaccine containing a toxin
• Diptheria
• Tetanus
(iii) Vaccine containing an attenuated (modified or weakened) organism which is alive but has been modified so that it
is not harmful
• Sabin polio vaccine (Taken orally, syrup or on sugar lumps)
• Purified antigen - genetically engineered vaccine
• Hepatitis B
REACTIONS OF THE IMMUNE SYSTEM
üImmediate allergic responses usually involve humoral immunity
üDelayed allergic responses usually involve cell-mediated immunity
Hypersensitive reaction: immune system
to an allergen is initiated by immunological mechanisms
which is usually mediated by IgE antibodies
Allergy: immune system
an inappropriate often harmful response of the immune system to normally
harmless substances
Allergen:
the substance that causes the allergic response
