I do not understand why individuals with type O- blood are often called universal donors and those with type AB+ blood are called universal recipients.
My thoughts on this are:
It should be that because O+ blood has all antibodies but no antigens that all other blood types including O- would be incompatible making O not a universal donor - so why is O the 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 - so why is AB 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+