10 replies to this topic

[caters]

 

How is it that O people can only get O blood but A, B, and AB people can get O blood?

I can see how Rh- is only compatible with Rh- but how is Rh+ compatible with Rh-?

It should be that because O+ blood(which is my blood type) has all antibodies but no antigens that all other blood types including O- would be incompatible making O not a universal donor.

Also if O is the universal donor it should be O+ that is the universal donor and O- that isn't because Rh+ is compatible with Rh+ and Rh-, not just Rh+ or Rh-.

It should also be that because AB- has all antigens and no antibodies that AB is not the universal recipient.

I can see how A is not compatible with B and vice versa but for blood groups how is O compatible with all blood types yet people with O blood can only recieve O blood?

Also how is AB not compatible with all other blood groups yet can recieve all blood groups so that AB+ is the universal recipient?

Here is what I would expect from blood group mixtures:

O-A: A clumping in O
O-B: B clumping in O
O-AB: AB clumping in O
and that being true for the reverse order as well
AB-A: AB clumping in A
AB-B: AB clumping in B
as well as the one that everybody knows which is A-B: A clumping in B and B clumping in A

I would also expect for Rh compatibility:
Rh- with Rh+: Rh- clumping in Rh+

How is all this except for the A-B compatibility wrong, especially the O being able to only receive O yet A, B, and AB can recieve O as well as other compatible blood groups.

Edited by caters, 25 May 2014 - 08:15 PM.

[pito]

Its the other way around: O- is the universal one, O+ not because "its" there (its +)

 

I dont have much time now to explain it more, but if you check the following websites, you should be able to understand it: http://www.worldbloo....org/groups.htm

http://www.redcrossb...ood/blood-types

http://en.wikipedia....wiki/Blood_type

 

AB can receive from all others because they have "everything" already in their blood.. especially AB+ ! AB- is a different story (they dont have the rh+ so can only receive from rh- bloodgroups (except the first time ever: they can receive fom all, but if they reveice from a rh+ group the first time.. they can develop antibodies and thus wont be able to receive from rh+ in the future.

[caters]

but positive is compatible with positive and negative whereas negative is only compatible with negative and from that standpoint it sounds like O+ should be the universal donor.

[Tabaluga]

An example (just consider AB system for the moment): If someone has 0, this means he has no antigens in his blood. Which means he is the universal donor, because his blood will not clump with a patient who has A (who has antibodies against 0 ) or with a patient who has B (has antibodies against A) or with a patient who has AB (has no antibodies against either A or B, because both antigens are native to him so obviously he doesn't autoreact, and is thus the universal recipient)

Think like this: The patient who gets the blood must not have antibodies against the blood he gets. So he can always get 0, because blood of the type 0 does not have an antigen that could be attacked by the patient's antibodies.

 

 

By the way, how is your "cell from scratch" going ?

Edited by Tabaluga, 26 May 2014 - 07:55 AM.

[pito]

but positive is compatible with positive and negative whereas negative is only compatible with negative and from that standpoint it sounds like O+ should be the universal donor.

 

Its actually very simple:

 

+ means that you have "it" (the antigen)

- means that you dont have "it"

 

if you have "it", it does not matter whether you receive blood with "it" or without "it".

 

If you dont have "it" you can only receive blood from people not having "it" because if you receive blood from someone who does have "it" you might react to it because "it" is an antigen....

 

 

Its seems you are mixing two things up: the receiver and donor.

 

For being a receiver: + is positive (you can receive from anyone , + or -) , for being the donor: you can only donate to everyone if you are - ! (here the - is "positive).

 

the "-" means: not having a certain antigen... so its good to give , "worse" for receiving.
 

[caters]

An example (just consider AB system for the moment): If someone has 0, this means he has no antigens in his blood. Which means he is the universal donor, because his blood will not clump with a patient who has A (who has antibodies against 0 ) or with a patient who has B (has antibodies against A) or with a patient who has AB (has no antibodies against either A or B, because both antigens are native to him so obviously he doesn't autoreact, and is thus the universal recipient)

Think like this: The patient who gets the blood must not have antibodies against the blood he gets. So he can always get 0, because blood of the type 0 does not have an antigen that could be attacked by the patient's antibodies.

 

 

By the way, how is your "cell from scratch" going ?

My cell from scratch is going fine. I have now the DNA sequence of at least 1 membrane protein if not more and in the DNA sequence I have exons highlighted around the text and coding exons with text and the area around the text highlighted as well as what human chromosome the gene is on. 

[caters]

An example (just consider AB system for the moment): If someone has 0, this means he has no antigens in his blood. Which means he is the universal donor, because his blood will not clump with a patient who has A (who has antibodies against 0 ) or with a patient who has B (has antibodies against A) or with a patient who has AB (has no antibodies against either A or B, because both antigens are native to him so obviously he doesn't autoreact, and is thus the universal recipient)

Think like this: The patient who gets the blood must not have antibodies against the blood he gets. So he can always get 0, because blood of the type 0 does not have an antigen that could be attacked by the patient's antibodies.

 

 

By the way, how is your "cell from scratch" going ?

Yes the antibodies that A has won't effect O but the antibodies that O have are against both A blood and B blood and so antibodies in O blood will make the other blood agglutinate and agglutination in the body is very bad.

[Tabaluga]

Oh, now I see where the problem is. What we are talking about is erythrocyte transfusion, which is usually meant when you talk about blood transfusion. So erythrocyte concentrates contain no antibodies, just their respective antigens. The antibodies are in the serum. Thus the situation you mentioned in your last post would arise when you transfund serum. For serum transfusion it's indeed the other way round - 0 is the universal serum recipient, and AB the universal serum donor.

[mdfenko]

another problem in your rationale is that you assume that blood type indicates presence of antibodies. antibodies are only produced when the offending antigens are introduced.

 

type "o" blood means it does not contain the "a" or "b" antigens (there is no "o" antigen, it means the absence of "a" and "b" antigens). therefore, it will not stimulate antibody production when given to type "a", "b" or "ab" recipients and will not be rejected.

 

giving type "a", "b" or "ab" to a type "o" recipient, on the other hand, will stimulate antibody production and will be rejected.

 

also, don't forget the rh factor.

 

in summary, type "o", rh negative is the universal blood donor and type "ab", rh positive is the universal blood acceptor.

[El Crazy Xabi]

Technically speaking, it does exist the "O" antigen, for the blood groups of the ABO system the antigens are the ABH. Type O blood only has H antigen and it is the precursor of antigens type A and B, that's why everybody can receive type O RBCs... or almost. There are few people who have the called Bombay phenotype which don't produce H antigen and react even against type O blood, but that's a weird case...

Respect to the production of antibodies, the anti-A and anti-B seems to be acquired from environmental exposure, not necessarily other blood types

e.g., bloodgroup B determinants [alpha-Dgalactose] cross-react with Gram-negative enterobacteriaceae such as E. coli, whilst bloodgroup A determinants [a-D-N-acetyl galactosamine] crossreact with influenza virus epitopes

In http://link.springer...039625.56296.6e

That's why you have anti-A or anti-B antibodies unless you are AB

[mdfenko]

the H antigen is, except in rare cases, present on all erythrocytes. the "o" type is simply an indicator for the absence of "a" and "b" antigen.

 

this wikipedia page gives some more information on blood type systems.