Immunology Flashcards
What is the immune system?
The body’s ability to resist or eliminate potentially harmful foreign materials.
What is immuinity?
Protection from harmful diseases.
Define innate immuinity.
Cells that are always ready to attack.
Why doesn’t innate immuinity always work?
Pathogenic microbes have evolvedto resist innate immuinity.
Define pathogen
Any microorganism that causes harm.
Name five pathogens.
Virus, bacteria, parasites, fungi and protozoa.
Are innate repsonsesspecific?
No, they are non-specific.
describe innate responses.
Innate responses can distinguish between human cells and pathogens but not the type of pathogen. They respond v quickly but have no memory and will create the same response.
How is adaptive immuinity stimulated?
By exposure to a microbe.
Name some external barriers.
Skin, mucus.
Name some of the body’s flushing features.
Saliva, tears, urine.
Describe adaptive immuinity responses.
Slow and can take a few days but remember pathogens.
Name the two types of immuinity.
Innate and adaptive.
Name the two types of inate immuinity.
Humoral and cellular.
Name external barriers relating to the following-
- Sweat
-Stomach
-Tears/ saliva
Sweat- high NaCl, lysozymes.
Stomach- digestive enzymes, gastric acid.
Tears/saliva- lysozymes.
Name some cells which are important in cellular innate immuinity.
Basophils, phagocytes.
Define phagocytes.
Cells which track down, engulf and destroy bacteria and pathogens.
Describe the six stages of phagocytosis.
- Movement of the pathogen towrads the microbe.
- Attachment of microbes to phagoyte surface.
- Endocytosis of microbe and formation of phagosome.
- Fusion of phagosome and lysosome.
- Killing of microbe through digestion by enzymes.
- Discahrge of waste materials.
Describe neutrophils.
Must abundant WBC.
Contains granules filled w many digestive enzymes which kill and destroy bacteria and other pathogens.
Describe monocytes.
Make up 5% of WBC’s.
Larger than neutrophils and can digest a lot more.
Describe macrophages.
Break down pathogens.
They process antigens and present them to the cells of the adaptive immunity to produce specific immune responses in the form of Ab and cytotoxic T cells.
What do CD4 cells do?
CD4 cells help control the activity of other cells and can help with triggering the immune system.
What disease can impact CD4 cells and how?
HIV
infects CD4 cells and makes more copies of itself.
What do CD8 cells do?
CD8 T cells mediate viral clearance by utilizing a variety of effector mechanisms to induce the apoptosis of virus-infected cells
Name two types of phagocyte/
Neutrophils
Marophages
Name some types of enzyme found in the granules of neutrophils.
Peroxidase enzymes
Acid and alkali phosphatases
What type of infection do neutrophils fight?
Bacterial
Fungi
What type of infection do lymphocytes fight?
Viruses
What part of the immune system are eosinphils part of?
Innate
What part of the immune system are mast cells part of?
Innate
What is the function of eosinphils?
Help against parasitic infections.
Name a feature of eosinphils.
Granules filled w digestive enzymes.
Assist w allergy and asthma
Name two features of mast cells.
Have enzyme filled granules
Have immunogloblin receptors.
What does immunoglobulin E play a part in?
Allergy sensitization
What does the immunoglobulin E antibody recognise?
Allergy related antigens.
What is histamine?
A compound which is released by cells in allergic and inflammatory reactions, causing contraction of smooth muscle and dilation of capillaries.
What is histamine considered to be?
Modulator
Sometimes considered a neurotransmitter.
When histamine reaches you skin, what does it cause?
Itchiness
What happens when histamine reaches blood vessels?
Causes them to vasodilate
What will histamine promote when it reaches the stomach?
Gastric acid secretion
What will happen when histamine reaches your lungs?
Causes contraction of the respiratory ways
Which cell is the least common WBC?
Basophils
Describe some features of basophils.
Contain large cytoplasmic granules with inflammatory mediators.
Where are basophils found?
In parasitic infection
