SH10: Immunity Flashcards Preview

BS1040: Microbiology and Cell Biology > SH10: Immunity > Flashcards

Flashcards in SH10: Immunity Deck (7)
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1

What is Collateral damage

The immune response causing pathogenesis

2

Two main arms of the immune system

1. Innate immunity- Deals with the fact that microorganisms grow very quickly. Immediate response, low specifity. Depend upon pathogen associated molecular patterns (PAMPS) (molecular features such as proteins, carbohydrates made, peptidoglycan presence and genome that a unique to the bacteria and viruses) These are all recognised as foreign from our innate and adaptive immune system
• Skin (barrier to pathogens) (also contain amphiphilic proteins which degrade pathogens and disrupt their membrane)
• Body secretions and fluids (barrier)
• Iron is essential for us but limiting for bacteria, so lactoferrin is a protein that helps us release iron
• Fever (optimum temp for immune enzymes to work, and try and kill pathogens)
• Phagocytes (cells engulf and destroy)
• Dendritic cells (go around the body looking for pathogens, find infected cell, kill cell and pathogen)
• Complement protein components identify bacteria and viruses, then start a cascade to kill them
2. Adaptive immunity- Deals with a more specific response that develops slowly. Slow response, high specifity and develops memory.
• Humoral (b lymphocytes, recognise and bind to pathogens, divide and make antibodies)
• Cell-mediated (t lymphocytes recognise cells infected, divide and bind to infected tissues and kill tissue and pathogen)

3

What is the immune system dependant upon?

Pathogen associated molecular patterns (PAMPS) (molecular features such as proteins, carbohydrates made, peptidoglycan presence and genome that a unique to the bacteria and viruses) These are all recognised as foreign from our innate and adaptive immune system.

4

Innate immunity has made factors that aid it

• Complement are blood bourn system of proteins have bad and good effects.
Mutations of the genes coding for the proteins can make you predisposed to a bacterial infection. If you have a heart attack or stroke, complement will start to attack your own body tissue.
They are activated in many ways (sugars/carbohydrates on the surface of bacteria_ and their job is to degrade/ punch holes in the membranes of viruses and bacteria to kill them.
• Interferon synthesis is stimulated by viruses making ds DNA. Interferons are made inside the cell, and move to other cells, binding to interferon receptors on the cell surface producing a cascade to the nucleus where genes are made that establish the anti-viral state of the cell. This prevents virus replication. This give the adaptive immune system to kick in.
• Natural killer cells bind to cells at random, looking for a naturally made proteins called MHC 1 (major histocompatibility complex)- if present, cell is not killed, but if it is not then proteins are released to kill the infected cell.

5

White blood cell types:

• Neutrophils; engulf cells and do phagocytosis.
• Monocytes/macrophages; phagocytosis present antigens on cell surface (APC) stimulate B cells and T cells
• Dendritic cells; phagocytosis present antigens on cell surface (APC) stimulate B cells and T cells
• Basophils; histamines and inflammation (localisation
• Mast cells; release histamine (inflammation), increase blood flow to increase localisation. Increase lymph flow
• Eosinophils; kill parasites

6

Describe B cells

Lymphocytes. Made when stem marrow cells pass through the bone marrow. Naive cells recognise pathogens make antibodies/ immunoglobulins. Leave memory cells.

7

Describe T cells

Lymphocytes. Made when bone marrow stem cells pass through the thymus. Bind to infected cells and kill cell. Leave memory cells.