Why O blood can transfuse to A blood?

[silvermoon]

although there is anti A in O blood, can it attack A red blood cell?

[victor]

Actually, it cannot now....it's only theorically like that...

[silvermoon]

The answer is anti A in O blood can attack A red blood cell in A blood, sure 100%. But the question is why?why we can transfuse blood O to A or O to B harmlessly?

[rg]

actually the theory is like that o blood group lacks both A and B antigens but has both a and b antibodies.since there are no A and B antigens to cause incompatibility and hence agglutination,so there is no danger of donation of o blood group and hence it is called a "universal donor".....this theory is approved correctly by all..

[kiekyon]

The answer is anti A in O blood can attack A red blood cell in A blood, sure 100%. But the question is why?why we can transfuse blood O to A or O to B harmlessly?

You are correct, people with type O blood have antibodies to group A and group B antigens. If a type O person is transfused with type A blood, the antibodies present in the type O person's blood will bind to the erythrocytes (red blood cells) in the transfused blood. This will lead to a hemolytic depletion of the transfused blood. Mismatched blood transfusion can also lead to renal damage (due to attempted clearance of the erythrocyte degradation products) and loss of circulatory stability.

So, in short, a person who has type O blood **will** "attack" type A blood, if they are unlucky enough to be transfused with it. This is why hospitals always type match and cross, to make sure that the blood they transfuse will not cause problems in the recipient. This is also why, in the absence of blood type screening, the default is to use Type O Rh- blood, as this is least likely to cause problems (and also why O Rh negative people are referred to as "universal donors" and type AB Rh positive people are referred to as "universal recipients" as theoretically, they could be transfused with any blood). There are more blood groups than A, B and O and Rh+/-, but these are the major ones.

[csin]

becasue blood type o have no antigens. blood type o is a universal donor BUT it cannot recieve blood from other types other than type o.

[weesper]

In answer to the primary question to argument thats been lacking so far is that when we talk of transfusing blood we are actually hanging on erythrocytes and not just 'total blood' that would also contain hemostatic factors and, also, the antibodies directed at other antigens that are indeed present in type O blood yet these are not transfused since its only this donors erythrocytes that are transfused. This is why they are universal donors. good luck