Antibody Screening & Identification Panels (in Immunohematology)

 


1. Objective:
To detect and identify unexpected antibodies in a patient’s serum that may react with red blood cell antigens, especially before transfusion.

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2. Principle:
Patient serum is mixed with reagent red cells of known antigen profiles. Agglutination indicates the presence of antibodies. Identification involves comparing reaction patterns with known antigen matrices.

3. Materials:

  • Patient serum/plasma

  • Screening and identification red cell panels

  • LISS or saline

  • Antiglobulin reagent (Coombs reagent)

  • Test tubes or gel cards

  • Centrifuge, incubator

4. Procedure:

  1. Mix patient serum with screening cells → incubate.

  2. Wash to remove unbound antibodies.

  3. Add antihuman globulin → check for agglutination.

  4. If positive, proceed to identification with an extended red cell panel.

  5. Compare agglutination pattern to known antigen profiles.

5. Result Interpretation:

  • No agglutination: No detectable antibodies.

  • Agglutination with specific cells: Suggests presence of particular antibody (e.g., anti-D, anti-K, etc.).

6. Clinical Significance:

  • Crucial in transfusion safety.

  • Prevents hemolytic transfusion reactions.

  • Used in prenatal testing for HDFN (Hemolytic Disease of the Fetus and Newborn).


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