Defense against Infectious Disease (6.3)
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Notes, Review & ExtensionsImmunology Notes (HL)HL Extension (11.1): Antibody Production and Vaccination |
First Line of Defense
100s of microorganisms live on and within your body
The skin:
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Blood Clotting
Cuts in your skin are sealed by blood clotting
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Coronary Thrombosis
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Coronary Thrombosis (CT) = Blood clots form in the coronary arteries
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Antigens vs. Antibodies
Antibodies are
Antigens vs Antibodies Antibodies production |
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Blood Typing using Antigens/ Antibodies
Blood typing uses antigens and antibodies. The "antigens" are protein markers on the outside of our red blood cells. Depending on what blood type you have, you will have different protein markers. These markers then react with specific antibodies which allow doctors, nurses, and hospitals to determine what blood type you have. You have 4 blood types (A, B, AB, and O) plus each can be positive (+) or negative (-) giving us 8 different blood groups.
Blood Type
Someone with A blood produced A antigens on their blood cells (triangles), but their immune system produces B antibodies as a way to recognize non-self and attack it. Vice versa for B blood. AB blood has both A and B antigens and as a result produces no antibodies, as this would mean attacking itself. O blood contains neither A nor B on the outside of their cells, and therefore the body produces both A and B antibodies.
- If you bodies produces the antibodies then you can not recieve this kind of blood.
- Hence, AB being the universal recipient as they can recieve blood from any other type and O blood being the universal donor because they can give blood to any other type, but can not recieve from any accept themselves.
Rh Group
The Rh group is a seperate antigen produced on the cells surface. This is what defines the positive and negative aspect of blood typing. If you have the antigen present you are positive (+), if the antigen is missing you are negative (-). This antigen can be present with any of the 4 blood types.
How antibodies are used to determine blood type in a lab (or emergency room):
Isolated antibodies from different people are used. When an unknown blood sample is presented, it is presented with the three different kinds of antibodies: A, B, and Rh. A reaction (coagulation) at any of these antibodies means it is positive for this antigen. Example:
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WHY IT MATTERS?
Blood type matters due to things like blood transfusions and transplants. If you put the wrong blood into a person their body will recognize it as foreign, and attack it. Usually this will kill them. However, if you replace depleted blood with the same type or one that will not react to the naturally occuring antibodies in the person, they will survive. When it comes to transplants this is a bit more complicated, as there are more categories than just blood type to consider. But the principle is the same. |
Antibiotics vs Vaccines
Antibiotics often work by blocking processes that only bacteria cells carry out. Viruses who do very little of their own processes, therefore can not be harmed via antibiotics because they do not contain cells or carry out these processes
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Vaccines work by boosting your immune system so that the immune system into a secondary response. This means if your body comes in contact with the disease, your immune system is already primed to deal with it. The reaction of attack is faster and strong usually resulting in you being unable to get sick. (For more information See Antibody Production and Vaccination, 11.1)
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AIDS & HIV
Human Immunodeficiency Virus (HIV) is the virus that causes the disease Acquired Immunodeficiency Syndrome (AIDS).
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COVID-19
Sars-CoV-2 is the virus that causes COVID-19
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