
Originally Posted by
TPhaoimnaes
Alright, thanks a lot

So if I understand correctly...
the answer to my question is that the reason there are different types of antigens on blood cells is because the immune system randomly generated a specific one, so the body could recognize it as part of itself.
Thanks

Not quite, say you're type A, this is hereditary. The surface antigen is determined by your genetics.
Now, your body produces white blood cells with a wide range of antigen specificity, this is random. However, during the process of making those T and B cells, your body filters out the cells that recognize self-antigens. This is to stop your white blood cells from attacking yourself.
So, if you have type A antigens on your red blood cells, you will not make any mature white blood cells that recognize A as "other" and attack it.