The Anti-H Lectin is a purified extract from seeds of Ulex europaeus. The reagent contains a phytohaemagglutinin which is virtually specific for the H antigen on human red blood cells. Anti-H Lectin is used to demonstrate the presence of H antigen on human red blood cells and in assessing the H secretor status of group ‘O’ individuals.
Major percentage of the population (80%) has soluble ABO blood group antigens present in their body fluids. These patients are known as ABH secretors while remaining 20% are non secretors. Secretors contain the following ABH antigens in their body fluids:
- O Secretors : Only H : A Secretors : A & H
- B Secretors : B & H : AB Secretors : A,B & H
- Non Secretors : None
Human red blood cells possessing H antigen will agglutinate in the presence of seed extract of Ulex europaeus containing phytoagglutinin specifically directed towards it. Saliva also contains water soluble ‘H’ antigen which gets neutralized by Anti-H Lectin.