4/5/2018. Duffy A? Duffy B? Duffy Three?! Panel Work-up 8. What is Fy3? Panel Work-up continued. The Duffy System. What is Fy3?

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1 Objectives Upon completion of this lecture, the listener will: 2 Blood Bank Combination Antibodies: A case study review of anti-f, -G, -U, and Fy3 LINDSEY WLOSINSKI, MLS(ASCP) CM,SBB CM HENRY FORD HOSPITAL, DETROIT MI Be aware of blood bank reactions associated with combination antibodies. Detect phenotypic reactions associated with combination antibodies Recognize transfusion requirements associated with combination antibodies Thinking Outside the Box 3 What you re here for today: 4 It is not unusual to uncover difficult patient scenarios in any clinical laboratory Sometimes uncommon blood bank antibodies show up during routine testing Having knowledge of some of these antibodies can aid in critical thinking and faster turnaround time It is good to have a sense of direction! Rare antibodies are fun to learn about in theory not always in practice while under a time-crunch Brief synopsis of four uncommon blood bank antibodies that can be unearthed in the clinical laboratory Anti-Fy3 Anti-f Anti-G Anti-U The setting 5 6 Henry Ford main campus hospital, Detroit MI 877 bed, level 1 trauma, and tertiary care facility Assist in blood bank needs of other HFHS hospital blood banks We have some reference lab abilities: i.e. Eluates, WARM Auto-adsorptions, Rest adsorptions General capabilities for antibody identification include: First Up Three antibody panels via automated platform 6-7 liquid antibody panels from various manufacturers Do not use proteolytic enzymes (i.e. ficin, papain) or sulfhydryl reagents (i.e. DTT) 1

2 Duffy A? Duffy B? Duffy Three?! 7 Panel Work-up 8 Patient: 65 y/o black male arriving for routine surgery. He has history of anemia and was transfused four units of PRBCs two years ago. Blood Type: O positive Antibody screen results: E k Fya Fyb Jka Jkb N S P1 Lea Leb AHG D C c e f Cw K M s 37 CC NT NT NT NT NT NT NT E k Fya Fyb Jka Jkb N S P1 Lea Leb AHG D C c e f Cw K M s 37 CC NT I (R1R1) II (R2R2) NT III (rr) NT Panagglutination with all screen cells Run antibody panel Unable to determine antibody specificity at this point NT NT NT Patient Cells 0 0 NT Still unable to determine antibody specificity Perform an auto control Run additional panel cells Panel Work-up continued 9 What is Fy3? NT NT NT NT NT NT NT NT NT Patient Cells 0 0 Is there anything unique on this cell? What s next? More panel cells What can we rule-out? Enzyme treatment Phenotype the patient for Fya and Fyb Extended phenotype Ficin 0 High prevalence antigen, found in 1971 (Reid,2007; Reid,2012) 68% of black donors, and 25% Israeli Arab donors are antigen-negative. Their phenotype is Fy(a-,b-) (Reid,2007) Although there is high frequency of Fy3 phenotypes among blacks, formation of the antibody is rare (Reid,2012; Shaz,2013) FY3 RBCs are resistant to malarial parasites p.vivax, and p. knowlesi (Reid,2012; Shaz,2013) What is Fy3? 11 The Duffy System 12 Fy(a-,b-) individuals have yet to make anti-fyb, due to a nucleotide change in the GATA-1 erythroid transcription factor that silences FY*B gene. These patients possess the Fyb antigen elsewhere, thus removing the possibility of anti-fyb formation (Reid,2007; Reid,2012; Shaz,2013; Daniels,2014) Anti-Fy3 formation is usually preceded by the formation of anti-fya (Reid,2012) Fy3 is resistant to proteolytic enzymes, unlike Fya and Fyb (Shaz,2013; Daniels,2014) Transfuse Fy(a-,b-) RBCs for patients presenting with this antibody Figure 1. Shaz,

3 13 What the Anti-f? y/o multiparous female currently admitted for ROM. She is 35 weeks pregnant. Up Next No history of transfusion Blood Type: A positive Antibody screen results: I (R1R1) II (R2R2) III (rr) NT What can we rule out? Run more panel cells to complete identification Panel Work-up 15 What is f? 16 Polymorphic (compound) antigen, first found in 1953 (Reid,2007, Reid,2012) NT NT NT NT Patient Cells All common, clinically-significant antigens have been ruled out So what is it? An anti-f? What can we do next? Phenotype the patient 35% Caucasian, 8% Black, and 88% Asian donors are antigen-negative (Reid,2007) The f antigen is expressed on RBCs with c and e antigens on the same haplotype (in cis) (Reid,2007) Anti-f is a compound antibody against cells with c and e antigens that are carried on the same protein; Dce/dce (Daniels,2014) The antigen is not expressed when c and e are on separate proteins (Reid,2012) What is f? Anti-f is useful in distinguishing DCE/dce from DCe/DcE (Reid,2012) Anti-f for typing is rare and is not found in the clinical lab Anti-ce = Anti-f (Daniels,2014) The f antigen is expressed on the Rhce protein, but the requirements Moving on for expression of the antigen are not understood (Reid,2012) R1R1 and R2R2 blood is f- and can be used for transfusion. Phenotype your patient for the c and e antigens prior to transfusion 3

4 OM-G 19 Panel Work-up y/o female presents for routine OB check-up. Patient is 6 weeks pregnant with her first child. No history of transfusion Blood Type: B negative Antibody Screen Results: I (R1R1) NT II (R2R2) NT III (rr) What can we rule-out? Run additional panel cells NT NT NT NT NT NT NT NT Patient Cells Have yet to rule out all clinically significant antigens Run additional panel Panel Work-up Continued 21 What is G? Polymorphic (compound) antigen, found in 1958 (Reid,2007; Reid,2012) NT NT NT NT NT NT NT NT Patient Cells Compound antigens have multiple C/c/E/e specificities encoded by the same gene (Daniels,2014) Anti-G is found in sera from rr (ce/ce) people with anti-d and/or Anti-C (Reid,2012) 16% Caucasian, and 8% Black donors are antigen-negative (Reid,2007) Almost all D-C- RBCS are G- and Almost all D or C RBCs are G (Chaffin,2017) What s left to eliminate? Phenotype the patient E antigen can be eliminated by phenotype Looks like anti-d,-c but is it? Figure 2. BBGuy.org, 2016 Anti-D, -C or Anti-G? Does it matter? 23 Adsorption/Elution for anti-g 24 Antibody often found with Anti-D and/or Anti-C so for transfusion purposes, it really doesn t matter (Harmening,2012; Chaffin,2017) Since Anti-G is commonly found with anti-d, this can confuse serological investigations of Hemolytic Disease of the Fetus and Newborn (HDFN) (Daniels,2014) Does mom need RhIg? anti-g = YES, anti-d =NO Allo-adsorption and elution techniques can be used to identify presence of anti-g when assessing HDFN and RhIg prophylaxis Figure 3. BBGuy.org, 2016 Adsorb the anti-d and anti-g onto the test cells, leaving the anti-c behind Eluate contains anti-d and anti-g, but not anti-c Figure 4. BBGuy.org, 2016 Adsorb the anti-g onto the test cells, leaving the anti-d behind Eluate contains anti-g only Adsorbed serum contains anti-d only 4

5 25 U have got to be kidding me 26 Last but not least 45 y/o Black male admitted for seizures. Has history of transfusion, and received four units of PRBCs three years ago. Blood Type: O positive Antibody Screen Results: I (R1R1) NT II (R2R2) NT III (rr) NT Unable to determine antibody specificity Run additional panel cells Panel Work-up 27 Panel Work-up Continued NT NT NT NT NT NT NT NT NT NT Patient Cells 0 0 NT NT NT NT NT NT NT NT NT NT NT Patient Cells Enzymes Ficin DTT Panagglutination at AHG for all cells tested Perform an auto control What can we do next? Run another panel Still unable to rule-out any antigens What could it be? High-incidence? Multiple? What steps can we take? Enzymes and sulfhydryl reagents Extended phenotyping Notice anything in the phenotype? uh oh The U antigen 29 What is U? 30 The S,s and U antigens are located on Glycophorin B The location of U antigen on the Glycophorin B structure shows how resistant this antigen is to enzyme treatment Found in 1953 and given name of U from the almost universal distribution of the antigen (Reid,2012; Harmening,2012) High prevalence antigen (Reid,2007) 1% of Black donors are antigen-negative and have a Serologic phenotype of S-, s- (Reid,2007; Reid,2012; Daniels,2014) The S-s-U- phenotype can result from homozygotic deletion of the coding region of GYPB, the gene coding GPB (Daniels,2014) Of S-s- RBCs, approx. 16% are weakly U and are called U var (Reid,2007, Reid,2012) This is brought on my a hybrid expression of GYPB (Daniels,2014) Antibodies that detect U variants can technically be called anti-u/gpb (Reid,2007; Reid,2012) Figure 4. Shaz,

6 What do we do? Need assistance from reference laboratory To confirm presence of anti-u and confirm absence of other alloantibodies To determine if patient is U- or is a U variant To procure appropriate units for transfusion Are there any questions? Family members of patients with anti-u should be tested for compatibility and are urged to donate blood for cryogenic storage (Reid,2007) Need to open up a dialogue with patient s clinician regarding rarity of their transfusion needs References 33 Reid, M. E., & Lomas-Francis, C. (2007). Blood group antigens & antibodies: A guide to clinical relevance & technical tips. New York: Star Bright Books. Daniels, G., & Bromilow, I. (2014). Essential guide to blood groups. Chichester, West Sussex, UK: Wiley-Blackwell.Reid, M.E., Lomas-Francis, C., Olsson, M. The blood group antigen facts book Reid, M. E., Lomas-Francis, C., & Olsson, M. L. (2012). The blood group antigen factsbook (3rd ed.). Amsterdam: Elsevier/AP. Shaz, B. H. (2013). Transfusion medicine and hemostasis: Clinical and laboratory aspects. London: Elsevier. Harmening, D. (2012). Modern blood banking & transfusion practices (Vol. 6). Philadelphia: F.A. Davis. Chaffin, J., MD. (2017, September 04). G-Wiz! Decoding the G antigen and Anti-G. Retrieved March 19, 2018, from 6