Topic 6 - Pack 4 Flashcards
What are the 4 main processes in the non-specific immune response?
Inflammation, lysozyme, antimicrobial properties (interferon), phagocytosis
What are the main purposes of the four processes in the non-specific immune response?
To destroy, prevent multiplication and spread of invading pathogens
What can happen if the four processes in the non-specific immune response fail?
Can lead to blood poisoning or widespread infection known as septic shock(as bacteria can get carried away from the site in the blood or in the lymph)
What is inflammation also known as?
Inflammatory response
Describe the process of the inflammatory response
– Infection/damage caused white blood cells and mast cells to release histamine
– histamine causes vasodilation of arterioles
– histamine causes increase in probability of capillaries
– plasma fluid and white blood cells and antibodies leak from blood to infection
– white blood cells begin to destroy pathogen
– interleukin released from white blood cells attracts more phagocytic cells to infection
– becomes red and hot
– causes oedema
Where is the enzyme lysozyme found?
Tears, nasal secretions, saliva
What is the substrate for the enzyme lysozyme?
The bacterial peptidoglycan cell wall
What is the result of lysozymes action?
– cell wall get broken down
– water enter cell
– cell bursts
– cells destroyed
What are interferons?
What does the protein interferon provide defence against?
They’re a group of proteins made by cells infected with a virus
Viral replication
Describe interferons mode of action
Diffuses out of cell into surrounding cells
Stimulates a pathway which makes cell resistant to infection by preventing viral replication
- inhibits viral protein synthesis
- limits the formation of new viral particles
What cells carry out the process of phagocytosis?
Phagocytes
– neutrophils
– macrophages
Describe the process of phagocytosis
– Bacterium binds to membrane receptors on the phagocyte
– membrane processes surround bacterium and engulfing it into phagosome
– lysosomes containing digestive enzymes fuse with the phagosome to form a phagolysome and bacterium is digested
– small vacuole buds off containing parts of bacterium
Definition of infection
Pathogen / microorganisms inside cells/tissues, they have evaded barriers
Definition of non specific response
Reacting and defending against a pathogen/something that is non self
What happens, regarding antigens, when a pathogen invades the body
– The antigens on its cell surface are recognise as foreign by white blood cells
– immune system is now activated
– immediate non-specific response is activated (general attack of anything foreign)
