Immunity and Disease Flashcards
What is innate immunity?
A fast response.
A defence mechanism that is place before infection.
e.g skin, mucous membranes, phagocytic cells, fever.
What is an adaptive immune response?
A slower response that occurs after infection.
Cell-mediated or humoral immunity.
What are non-specific defences?
Prevent infections from viruses and bacteria.
e.g infarct skin, mucus and cilla.
Explain the defence mechanism of skin.
The outer later of skin is made up of keratin. Forms a mechanical barrier that is hard to penetrate and is waterproof.
Dead skin cells are continuously shed, making it hard for bacteria to colonise.
Sweat and oil contain anti-microbial chemicals.
Explain the defence mechanisms of the mucous membranes.
Flow of mucus washes bacteria and viruses off the mucus membrane.
Cilla in respiratory tract lines and moves mucus.
Acid in the stomach and vagina acts as a protective layer.
Enzymes in the saliva and eye breakdown bacteria.
List some examples of non-specific responses to infection.
Macrophages release IL1 and IL6 inflammatory mediators.
Fever- most bacteria grow optimally at lower than body temp. Fever fries them.
Pain, swelling and redness- increases capillary permability and blood flow brings more phagocytotic cells to the area of infection.
Acute phase proteins released from liver bind to bacteria and activate complement proteins.
List specific adaptive responses to immunity.
Relies on antigens.
Lymphocytes travel quickly around the body in the blood or lymphatic system.
What are lymphocytes?
Produced in the bone marrow.
B-cells are produced in the bone marrow but then concentrate in the lymph nodes and spleen.
T- cells mature in the thymus.
What do B-lymphocytes do?
Produced in bone marrow.
Concentrate in the lymphnodes and sleep.
Secrete antibodies that are involved in humeral activities and recognise pathogens outside of cells.
What do T-lymphocytes do?
Destroy antigens and recognise and destroy cancer cells.
Stimulate B cells.
How do T-cells signal immune response.
Helper T-cells are stimulated by an antigen.
Are cytotoxic cells that stimulate B-cell division.
How do B-cells signal immune response.
Glycoproteins.
List some examples of primary immunodeficiency.
Chemotherapy
HIV- leading to AIDS due to a decline in CD4T cells.
Spleonectomy
Bone Marrow Dysfunction.
List some examples of secondary immunodeficiency.
Malnutrition Burns Uremia Diabetes Drugs AIDS
List some examples of a hyperactive immunodeficiency.
Hypersensitivity- Anaphylaxis/Allergy
Autoimmunity- Diabetes, coeliac, MS, hasimotos thyriodits.
