Antigen Typing

AGTYP

PINK (BB)
RBC Unit

Common Antigen Typings:  C, c, CW, E, e, FY^a, FY^b, JK^a, JK^b, Kell K and k, S, s

Antigen typing is not required on units for patients with -M, -N, -Le^a, -Le^b, -P₁, -Xg^a.

The antigen type of a patient or a unit is determined by testing the red blood cells with the specific antisera. Agglutination of the cells indicates the presence of the relevant antigen, while no agglutination indicates it absence. The absence of the antigen is used as confirmation of patient alloantibody identification. Presence or absence of antigen in a sample from an RBC unit is helpful in explaining positive crossmatches and selection of units likely to be compatible with a patient's antibody if specificity is known.
 

• Antibody Identification.
  • A negative antigen type helps to confirm the specificity of an antibody from that patient.
• Phenotypically matched Donor units.
  • Sickle cell patients may require units negative for all the common antigens that they lack to prevent antibody production.
  • Patients with a warm autoantibody may require units negative for all the common antigens that they lack when it is not possible to find compatible units.
  • Patients with clinically significant antibodies should receive red cells lacking the corresponding antigen(s), whether or not the antibody is currently reactive.
• Phenotyping Fathers.
  • The phenotype of the Father helps to determine the possibility of HDN when a Mother has an antibody.