Question

7. Explain connections between role of glycoproteins, blood groups and blood donor compatibility

Answer 1

Erythrocytes in human blood(RBCs ) have many glycoproteins and glycolipids attached to its cell membrane that have antigenic properties.The type of glycoproteins and glycolipids are unique to an individual.

There are 2 major classification for human blood types

1 ABO grouping

2 Rh system

ABO grouping is base on the difference in glycoproteins present on the surface of red blood cells.Glycoproteins are those proteins in which carbohydrates are attached to its surface.

For type A individuals-Type A glycoproteins attached.

Type B individuals-Type B glycoproteins attached.

Type AB individuals- Both A and B glycoproteins attached.

Type O individuals have no glycoproteins attached.

ABO blood type is commonly determined by using antibodies specific for type A and type B glycoproteins. Antibody-A (Anti-A) and Antibody-B (Anti-B) combine with A and B antigens, respectively. The binding of these antibodies to the surface antigens of red blood cells will result in clumping, or hemagglutination.

ABO typing of a blood sample:

Blood sample mixed with type A specific antibody -------> hemagglutination is observed.

This result indicates that type A glycoproteins are present on the red blood cells.

Blood sample is mixed with type B specific antibody -------> NO hemagglutination

This result indicates that type B glycoproteins are NOT present.

Blood donor compatibility.

blood group	donate blood to
A+	A+,AB+
O+	O+,A+,B+,AB+
B+	B+,AB+
AB+	AB+
A-	A+,A-,AB+,AB-
O-	EVERYONE
B-	B+,B-,AB+,AB-
AB-	AB+,AB-