BLOOD 4 Flashcards
________ of the ABO system
present on the surface of RBCs
determine blood types.
Antigens
ABO class of antigens are \_\_\_\_\_\_\_\_\_\_\_\_ molecules
carbohydrate
Antibodies of the ABO system, usually of the ___ ________, are classified as “naturally occurring” antibodies
IgM class
What dictates the expression of ABO antigens on RBCs ?
Gene -DNA - RNA- protein
What do ABO genes code for?
Enzymes (protein) of the ABO system
What do ABO not code for?
Surface ABO antigens
The enzymes coded by the ABO genes are added to on the
Specific terminal carbohydrate molecules to the surface of the RBC
A type blood info
Genotype: AA or AO
Antigens on RBC: A
Antibodies on plasma: anti-B
B type blood info
Genotype: BB or BO
Antigens on RBC: B
Antibodies on plasma: anti-A
AB type blood info
Genotype: AB
Antigens on RBC: A and B
Antibodies on plasma: neither
O type blood info
Genotype: OO
Antigens on RBC: neither
Antibodies on plasma: anti-A and anti-B
How is ABO blood type determined?
• An unknown sample of a persons blood is separated into RBC and plasma fractions.
• A drop or two of the
RBC are then mixed with a known solution containing either anti-A or anti – B antibodies
• The mixture is observed for RBC aggulation or clumping
What is Agglutination?
Aggulation is the process of having the red blood cells broken down and the hemoglobin is released.
What is the result of a mismatch during a blood transfusion?
Clumping or hemolysis
What can type A blood revive from ?
A and O
What can type B blood revive from ?
B and O
What can type AB blood revive from ?
AB and A and B and O
What can type O blood revive from ?
O
Antigens of the Rhesus system are
protein molecules and form integral part of the RBC membrane
For Rh blood types, Dominant “D” gene (D) codes for
D antigens on surface of RBC
In Rh blood types, Presence of D antigen makes the individual
Rh positive (Rh + ve)
Deletion of “D” gene implies the absence of D antigens on RBC and make the person
Rh negative (Rh -ve)
Rh+ type blood info
Genotype: DD or Dd
antigens on RBC membrane: D
Antibodies in plasma: no anti-D
Rh- type blood info
Genotype: dd
antigens on RBC membrane: no D
Antibodies in plasma: no anti-D
Antibodies of the Rhesus system are of the
IgG class.
Only _____ people can produce these antibodies after exposure to D antigen.
Rh –ve
Mismatched blood transfusion in the Rh system
• Rh- person with no anti-D
antibodies is exposed
accidentally to Rh + blood
during transfusion
• Rh- person develops anti-D
antibodies
• The same Rh- person is
exposed by mistake to another
transfusion of Rh+ blood
• Anti-D antibodies will bind to
Rh+ RBC and cause clumping and hemolysis
Solution for thesis mismatch between mother and child
a mother is given an injection of some immunoglobulins so that when the mother is exposed to the Rh+ for the first time it can bind it the Rh+ cells and mask/neutralize the cells form, being exposed into the mothers immune system, so the mother doesn’t produce any d antibodies.
