Why Doesn't Agglutination Occur in Blood Transfusions from O Group Donors?

[Entanglement]

I'm really confused about blood transfusion, I know that O group is a universal Donner but how since it has both antibodies A,B, why doesn't agglutination happen? For an example o group is donated to an individual with A blood group why doesn't the antibody A of O group cause Agglutination in the recipient blood since a got antigenes A

 

[Simon Bridge]

afaik: Type O is no longer considered to be a strict "universal donor" for just the reasons you point out.
See, for eg. http://www.mayoclinic.com/health/universal-blood-donor-type/HQ00949

 

[Entanglement]

I can't understand how can O group be donated to any other group without transfusion ??

 

[Simon Bridge]

You don't donate blood to another blood group - you donate it to a blood bank.
You mean you don't understand how O blood can be transfused into a patient with another blood type - ever?

It is because type O has neither A nor B antigen.
http://anthro.palomar.edu/blood/ABO_system.htm

 

[Entanglement]

Yes I mean how can it be given to another patient of another blood group without agglutination

 

[Simon Bridge]

Yes I mean how can it be given to another patient of another blood group without agglutination

Well...

It is because type O has neither A nor B antigen.
http://anthro.palomar.edu/blood/ABO_system.htm

...
There's two parts to blood typing.

 

[Enigman]

 

[Evo]

I'm really confused about blood transfusion, I know that O group is a universal Donner but how since it has both antibodies A,B, why doesn't agglutination happen? For an example o group is donated to an individual with A blood group why doesn't the antibody A of O group cause Agglutination in the recipient blood since a got antigenes A

This might help, the rest of the page has additional useful information.

By way of example: considering the transfusion of O Rh D negative blood (universal donor blood) into a recipient of blood group A Rh D positive, an immune reaction between the recipient's anti-B antibodies and the transfused RBCs is not anticipated. However, the relatively small amount of plasma in the transfused blood contains anti-A antibodies, which could react with the A antigens on the surface of the recipients RBCs, but a significant reaction is unlikely because of the dilution factors. Rh D sensitization is not anticipated.

Additionally, red blood cell surface antigens other than A, B and Rh D, might cause adverse reactions and sensitization, if they can bind to the corresponding antibodies to generate an immune response. Transfusions are further complicated because platelets and white blood cells (WBCs) have their own systems of surface antigens, and sensitization to platelet or WBC antigens can occur as a result of transfusion.

With regard to transfusions of plasma, this situation is reversed. Type O plasma, containing both anti-A and anti-B antibodies, can only be given to O recipients. The antibodies will attack the antigens on any other blood type. Conversely, AB plasma can be given to patients of any ABO blood group due to not containing any anti-A or anti-B antibodies.

http://en.wikipedia.org/wiki/Blood_type#Universal_donors_and_universal_recipients