With "unknown antibodies" you might mean irregular antibodies. In this case probably anitibodies against K (anti-K) a subtype of the Kell-bloodtype. Causes could be (including but not limited to): - You got a transfusion of bloodcells - You were pregnant
Mixing red cells and corresponding antibodies
Rheumatic endocarditis
the answer is unknown
It was unknown.
the Bolshevisk revolution in Russia and subsequent formation of the USSR.
by discovering antibodies
No, an allergic reaction is typically caused by a release of histamines from the eosinophils. Antibodies are produced by lymphocytes in response to a bacterial infection.
Over-speculation and Jackson's financial policies.
something that caused the big bang is scientifically unknown
No cause has been revealed yet.
The cause of the fire remains an unknown.
His cause of death is unknown.