Antibody Screening tutorial Discuss the importance of antibody screening. Describe characteristics of antibody screening cells. Describe the antibody screening procedure. Interpret antibody screening results. P Chimkupete BIOM3011: Haematology and Transfusion Science

Case study Patient 4 a 62-year-old lady arrived at A&E with bleeding oesophageal varices. She has three children, the youngest is 33 years old. She received two units of RBCs five years ago when she was admitted for hip surgery. This time the doctor has requested three units of red cells. You are provided with ABO and RhD blood grouping, antibody screening as well as antibody identification results for the patient. Interpret these results and suggest any further confirmatory tests Suggest steps you would take to find suitable blood for transfusion. Highlight the clinical significance of any antibody you identified.

Case study Cell group RhD Serum group Antibody screen anti-Aanti-Banti-DA 1 cellsBcellsSCISCIISCIII ResultMF ABO, RhD typing and antibody screen results Cell group A Cell group A RhD Positive RhD Positive Serum group A Serum group A Antibody screen positive Antibody screen positive

Case study Cell group RhD Serum group Antibody screen anti-Aanti-Banti-DA 1 cellsBcellsSCISCIISCIII ResultMF ABO, RhD typing and antibody screen results MF = mixed field agglutination; double population. MF = mixed field agglutination; double population. Mixture of antigen positive and antigen negative red blood cells. Mixture of antigen positive and antigen negative red blood cells. e.g. group O + group A cells

Case study Cell group RhD Serum group Antibody screen anti-Aanti-Banti-DA 1 cellsBcellsSCISCIISCIII ResultMF ABO, RhD typing and antibody screen results Causes of mixed field agglutination. Transfusion of group A patient with group O blood. Transfusion of group A patient with group O blood. Post bone marrow transplant. Post bone marrow transplant. Subgroup A 3. Subgroup A 3. Chimeric twins. Chimeric twins.

What is antibody screening? Deliberate testing of patient’s serum or plasma with antibody screening cells to screen for the presence of clinically significant antibodies. Deliberate testing of patient’s serum or plasma with antibody screening cells to screen for the presence of clinically significant antibodies. Early detection of antibodies Early detection of antibodies

When and Why? Blood and plasma donors Investigation of suspected transfusion reactions Patients requiring transfusion Pregnancy To detect antibody in patent which might react with donor RBC antigens. To detect antibodies in the mother which might react with the baby’s RBC antigens. To detect antibodies in the donor which may react with patient’s RBC antigens. To detect presence of an antibody which may have caused a transfusion reaction.

Antibody screening cells Carefully selected from group O donors to have a good expression of a wide range of clinically significant antigens. e.g. C, c, D, E, e of the RH blood group system and others..K, k; Fy a,Fy b ; Jk a,Jk b ; S,s, M,N; P 1

Profile of Antibody Screening cells. SC Rh CcDEeMNSsPLu a KkLe a Le b Fy a Fy b Jk a Jk b Antibody screening cells (SC) have clinically significant antigens from various blood groups. Rh blood group antigens MNSs Kell Lewis DuffyKidd

Profile of Antibody Screening cells. SC Rh CcDEeMNSsPLu a KkLe a Le b Fy a Fy b Jk a Jk b IR1R1R1R = Antigens present on antibody screening cells SCI 0 = antigens absent on SCI

Profile of Antibody Screening cells. SC Rh CcDEeMNSsPLu a KkLe a Le b Fy a Fy b Jk a Jk b IR1R1R1R IIR1R2R1R = Antigens present on antibody screening cells SCI and II 0 = antigens absent on SCI and SCII

Profile of Antibody Screening cells. SC Rh CcDEeMNSsPLu a KkLe a Le b Fy a Fy b Jk a Jk b IR1R1R1R IIR1R2R1R IIIrr = Antigens present on antibody screening cells. 0 = antigens absent on SCI, II and III

How is it performed? Antibody screening cells are added. Patient’s serum/ plasma added to tubes. Results are read after incubation and centrifugation.

Antibody Screening results SC Rh CcDEeMNSsPLu a KkLe a Le b Fy a Fy b Jk a Jk b IR1R1R1R IIR1R2R1R IIIrr Patient’s serum/plasma tested against antibody screening cells. Patient 1 SCIAT I2 II0 III0 Example of antibody screening results.

Antibody Screening profile SC Rh CcDEeMNSsPLu a KkLe a Le b Fy a Fy b Jk a Jk b IR1R1R1R IIR1R2R1R IIIrr Patient 2 IAT Patient 1 SCIAT I2 II0 III0 Example of antibody screening results.

Antibody Screening profile Patient 2 IAT Patient 1 SCIAT I2 II0 III0 Example of antibody screening results. Patient 3 IAT SC Rh CcDEeMNSsPLu a KkLe a Le b Fy a Fy b Jk a Jk b IR1R1R1R IIR1R2R1R IIIrr

Antibody Screening profile SC Rh CcDEeMNSsPLu a KkLe a Le b Fy a Fy b Jk a Jk b IR1R1R1R IIR1R2R1R IIIrr Patient 2 IAT Patient 3 IAT Patient 1 SCIAT I2 II0 III0 Patient 4 IAT Example of antibody screening results.

Antibody Screening profile SC Rh CcDEeMNSsPLu a KkLe a Le b Fy a Fy b Jk a Jk b IR1R1R1R IIR1R2R1R IIIrr Patient 2 IAT Patient 3 IAT Patient 1 SCIAT I2 II0 III0 Patient 4 IAT Example of antibody screening results. Patient 5 IAT 0 3 0

Summary Early detection of antibodies essential to prevent HTRs and HDFNB. Early detection of antibodies essential to prevent HTRs and HDFNB. Antibody screening cells specially selected for strong expression of a wide range of clinically significant antigens. Antibody screening cells specially selected for strong expression of a wide range of clinically significant antigens. Patient’s serum is tested against antibody screening cells. Patient’s serum is tested against antibody screening cells. A positive reaction means an antibody is present. A positive reaction means an antibody is present. Further test is antibody identification. Further test is antibody identification.