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Differences in blood

  1. Dec 24, 2007 #1
    Human blood is human blood right? So is the blood of caucasians, white people, black people etc all the same? What are the differences between the blood of some humans and the blood of others, other than blood type and having infections like aids?

  2. jcsd
  3. Dec 24, 2007 #2


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    Here is some information on blood types.

    see entire paper

  4. Dec 24, 2007 #3
    I mean I know that say...one type of blood will be different from other types, ie AB and O...but when the blood types are identical what are the differences between them
  5. Dec 24, 2007 #4
    The only differences may be the RH {rhesus} factors.
  6. Dec 24, 2007 #5
    Is the rhesus factor something to be concerned about if you're getting a blood transfusion, like if you were in a car accident? Does anything involving the rhesus factor matter regarding the blood, if you're getting it in a transfusion or something? I thought all you needed to worry about was blood type, and whether it was disease/drug free?
  7. Dec 24, 2007 #6
    would animal blood in a human kill the human, or damage it in some way? Like if somebody got animal blood instead of human blood after a car accident?
  8. Dec 25, 2007 #7
    How much blood would you lose before dying? I mean how much blood do people normally have in them and how little would you have to have in you to die?
  9. Dec 26, 2007 #8
    The amount of blood depends on the body size. A large person can have as much as 12 pints, the loss of 4 or 5 pints would have grim results.
    If Rh-positive blood is transfused into an Rh-negative person, the latter will gradually develop antibodies called anti-Rh agglutinins, that attach to the Rh-positive red blood cells, causing them to agglutinate. Destruction of the cells (hemolysis) eventually results.
    Last edited: Dec 26, 2007
  10. Dec 26, 2007 #9
    I've heard that people often die from blood transfusions
    Is that because they've lost blood/had injuries? Is that why blood transfusions are so bad for the immune system?
  11. Dec 26, 2007 #10
    What things, other than diseased blood, other than rhesus factors, but like the rhesus factor, would be an issue regarding the content of the blood?
  12. Dec 27, 2007 #11
    For blood transfusions, type and rh are the only tests performed for compatibility. There may certainly be proteins and other blood products that are not disease related but nonetheless pathogenic to a specific individual, but they are not routinely tested for these (I'm no geneticist, but I worked in a lab that performed type and rh for transfusions, pregnancies, etc.).
  13. Dec 27, 2007 #12

    jim mcnamara

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    Other factors:
    pathogens that are not tested for, e.g., various flavors of hepatitis like hepatitis C or uncommon (in temperate zones) tropical diseases.
    abnormal levels of hormones
    medicines like antibiotics

    A lot of this is stuff is screened out one way or another, but there is no absolute guarantee that when you need blood it will not cause problems for you. An example:Early on in the HIV epidemic, blood supplies became unkowingly contaminated with HIV virus from donors. The people who received the blood became HIV positive. HIV is screened out now.

    Look up nosocomial or iatrogenic.
    Last edited: Dec 27, 2007
  14. Dec 27, 2007 #13


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    It's not "often" that they die from blood transfusions, but mismatches can occur. People may die from blood loss in spite of a transfusion, if the blood can't be replaced quickly enough, or too much damage has already occurred before they got to the hospital for the transfusion.

    If a mismatch in blood occurs, the immune system will react to the "foreign" substance (i.e., the transfused blood cells). When this happens throughout the entire body, because something like blood goes everywhere in the body, this would be severe and potentially lethal.

    Blood from other species would not be compatible because proteins either composing the blood cells, or carried in the blood, would be somewhat different, and thus would be recognized as "foreign" when transfused.

    The same considerations are made for organ transplants. There are other antigens on the surfaces of cells called Major Histcompatibility Complexes (MHCs) other than those used for simple blood typing. For a transplant, because you're not just temporarily replacing cells that will die and be replaced by the body in a short time, it's important to get more of them matched than is done for blood transfusions (the blood cells in the transfusion don't have to live very long). People receiving organ transplants are also put on very powerful immune suppressing drugs to further prevent the immune system from being activated by introduction of the "foreign" organ.

    Something I've read about somewhat recently, but have not had a chance to look into in more depth, is that there may be some issues of using whole blood from women who have already had children for transfusions (other components can still be used, so no reason for women to stop donating blood). If I'm recalling that correctly, the issue was that there is just enough crossing of cells across the placenta (one of the reasons Rh factor is an important consideration during pregnancy) that antibodies are present in their blood that can attack the recipient even if they are type matched.

    What one has to keep in mind is that someone who is being given a transfusion is getting it because they are already critically injured/ill and the risk of a complication from the transfusion is less than the risk of dying from the blood loss itself.
  15. Dec 27, 2007 #14
    So do you have to consider Major Histcompatibility Complexes (MHCs) when getting a blood transfusion, what do those have to do with blood transfusion?

    How often does the body replace/create blood and how much does it replace/create when it does that?

    How old are the people who donate to red cross etc- what's the minimum donor age?

    If you get a blood transplant do you have to take immune suppressing drugs? What if it's a big transplant, do you have to take immune suppressing drugs even if the blood type etc is the same?
  16. Dec 27, 2007 #15
    if somebody loses half their blood or something like that, but they're in a hospital, how quickly can it be replaced in a blood transfusion?
    I think with red cross blood, you can be like 80 and give blood right? But minors can't give blood to legal reasons? Does the age of a person you're getting blood from matter at all? Like if an 80 year old got a 10 year old's blood or a 5 year old's blood would that mess the 80 year old up or would it not cause any problems?
  17. Dec 28, 2007 #16
    I guess one question I had is, I read about where they hooked an old mice up to the blood circulatory system of a young mouse and the old mouse healed fast and all that and then they said well there would be a huge immune response if humans did that because the mice were genetically identically. But if the blood type was compatible, and the rhesus factor was compatible, would there be a huge response if the blood systems of two humans were connected? I mean I suppose you couldn't do that without risks, what would the risks be if the systems were disease free and stuff? And how different would that be from getting blood but not being hooked up to another human?
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