Matching blood groups

[sdekivit]

I'm aware of how blood groups are matched but what I can't understand is WHY blood group O may donate to blood group A when blood group O contains agglutinin a!!!! I was wondering if the agglutinins were removed by some process before being transfused into another person!

why can O donate to A --> thus: why can A receive O. You also must remeber: blood clotting occurs when the receiver produces agglutinins against the donated bloodgroup

--> O doesn't contain any agglutinogen and therefore can be donated to blood type A patient (which produces agglutinine B but there's no agglutinogen B in blood type O )

--> it's in the same cases with other blood types --> O is universal donor.

[biostudent84]

why can O donate to A --> thus: why can A receive O. You also must remeber: blood clotting occurs when the receiver produces agglutinins against the donated bloodgroup

--> O doesn't contain any agglutinogen and therefore can be donated to blood type A patient (which produces agglutinine B but there's no agglutinogen B in blood type O )

--> it's in the same cases with other blood types --> O is universal donor.

Good answer! It also helps to explain how O is a universal reciever!

[Dr.Stein]

Just little notes:

1. O is NOT a universal donor anymore, and AB is NOT a universal recipient anymore. Those statements are nonsense now. O must be only for O and AB must be only for AB. The explanation for this is based on immunological view that is about antigen-antibody. I think most of you already know about this, but if someone wants more explanation I will help you with all my pleasure

2. It is TOTALLY different between agglutination and blood clotting. Agglutination is blood clumping whereas blood clotting also known as coagulation. Agglutination is when blood corpuscles are bond together by the presence of their antibody (agglutinogen-agglutinin reaction). Coagulation is when blood corpuscles are trapped in fibrin network resulted from wounds that break vessels.

[zenith_beth]

Thanks! Actually today I came across this statement on a textbook : "Although group O possesses a and b antibodies, when the donated blood forms a relatively small proportion of the total blood volume, there will be very little agglutination of the recipients's cells because the donated plasma is diluted so much by the recipient's blood. However in major transfusions the blood group must be matched more accurately." So Dr. Stein is this statement correct please?

[MrMistery]

Yeap, generally only one transfusion from O type is allowed, and even then, it should be under 500mL

[sdekivit]

Just little notes:

1. O is NOT a universal donor anymore, and AB is NOT a universal recipient anymore. Those statements are nonsense now. O must be only for O and AB must be only for AB. The explanation for this is based on immunological view that is about antigen-antibody. I think most of you already know about this, but if someone wants more explanation I will help you with all my pleasure

also depends on rhesusfactor, but there excists a universal donor and acceptor, knwon to be O(-) and AB(+).

indeed agglutination is different then blood clotting. But agglutination is the correct term, but in the view of the patient it's the same complication as blood clotting.

[Dr.Stein]

Thanks! Actually today I came across this statement on a textbook : "Although group O possesses a and b antibodies, when the donated blood forms a relatively small proportion of the total blood volume, there will be very little agglutination of the recipients's cells because the donated plasma is diluted so much by the recipient's blood. However in major transfusions the blood group must be matched more accurately." So Dr. Stein is this statement correct please?

Yeah. When O donated to A, the antibody a from O will react with antigen A from A. When O donated to B, the antibody a from O will react with antigen B from B. The agglutination is not much but, however, it is harmful. That's the background.

sdekivit: Thanks again You are a good partner

[zenith_beth]

Thanks you guys!!!

[nora2310]

hi, can anyone describe the strucutes of:
A antigen
B antigen
H antigen

is it basically that they are glycoproteins?

i found 2 conflicting meaning for H antigens- one source mentions that it is found in bacterial flagella and is heat labile and another source mentions it is a precursor of A and B and is expressed on O group individuals!

i would appreciate if someone can clarify this for me
thanks

[MrMistery]

The antigene in O group is called 0 antigene. This is where A and B antigenes are created from. No idea what H antigene is

[nora2310]

thanks alot