So if an individual has blood type B, that means they have a gene that codes for antigen B. And all the red blood cells will contain membrane bound antigen B glycoproteins as shown in green. And so this will be the self antigen. And what that means is our immune system will not produce any antibodies against this antigen B, but now will produce antibodies against antigen A because it doesn't have any antigen A on that protein. So this is blood type A and this is blood type B. Blood type A contains antigen A and antibodies against antigen B, while blood type B contains our membrane bound antigen B and so contains antibodies against antigen A.