BLOOD-GROUPS-new.pptx Blood transfusion medicine

Blood transfusion medicine

1. BLOOD GROUP DR.JA OLANIYI COSULTANT HAEMATOLOGIST DEPT OF HAEMATOLOGY UCH, IBADAN.

2. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> BLOOD GROUP SYSTEMS Group of RBC antigens (Ags) coded for by alleles at a single gene locus or by linked loci Alleles usually co-dominant; occasional amorphs Sometimes expression is affected by modifier genes at a different locus

3. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> The Basics Of Blood ANTIGEN >400 Agglutinogens on the cell membrane W.B.C. & Platelet R.B.C. Plasma ANTIBODY Natural & Immune Agglutinins/ Isoantibodies Antigen-Antibody reaction on the cell surface  Hemolysis

4. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> The Basics Of Blood Controlled by genes at unknown No. of chromosomal loci . Appearance by 40 days of I.U. Life- unchanged till death. Also present in tissues & tissue fluids. Blood group system: A group of antigens controlled by a locus having a variable no of allele genes. Antigens: -

5. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> The Basics Of Blood > 15 blood group systems are recognized : ABO, Rh , Kell, Duffy, MN, P, Lewis, Lutheran, Xg, Li, Yt, Dombrock, Colton, Public antigens & Private antigens. Blood type :- means individual antigen phenotype which is the serological expression of the inherited genes Most of these blood group antigens have been found to be associated with hemolytic disease . However– ABO & Rh account for 98% Antigens: -

6. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> The Basics Of Blood Alloantibodies / Agglutinins Natural IgM Iso / immune antibodies IgG Formed in response to foreign R.B.C. or soluble blood group substance. Antibodies: -

7. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> The Basics Of Blood Antibodies are formed against most of the major group antigens and are present in almost all individuals when the antigen is absent . In most other minor systems , natural antibodies to the antigens are found occasionally but their anitgenicity is low. The immune antibodies are also rare ( except –Kell & Duffy) Most of them are IgM type . React poorly at body temp. ( except anti-A & anti-B), but agglutinate R.B.C.s at 5-20°C Usually do not cross placenta . Natural Antibodies: -

8. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> The Basics Of Blood In contrast the immune or isoantibodies are IgG. Best react at body temp. & readily cross placenta. Most antibodies are complement binding notable exceptions being Rh & MN . Immune Antibodies: -

9. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> Antibodies Can Be Detected by: - Saline agglutination test (SAT). Tests using cells suspended in colloid media . Tests using enzyme-treated cells- Rh & occasional antibodies. Indirect antiglobulin ( Coomb’s test) - wide spectrum. Antibodies may be Complete / Incomplete   IgM IgG Detected by  SAT b, c, d

10. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> ABO Blood Group System ABO system is controlled by allelic genes A1, A2, B, O located on the long arm of chromosome 9 The loci of ABO & H are not genetically linked A1 & A2 genes perform same function but have a different rate constant The O gene is an amorph & functionaly silent

11. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> ABO Blood Group System The H antigen is a precursor to A & B Secretors & nonsecretors – Se & se genes control the production of a flucosyl transferase, which controls the production of H, A & B antigens in tissues

12. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> Structure of A & B Antigens H B A

13. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> Inheritance of ABO and Rh(D) Mother Group A AO Rh(D) pos Dd Father Group B BO Rh(D) pos Dd Group A AO Rh(D) pos Dd Group B BO Rh(D) pos Dd Group O OO Rh(D) neg dd

14. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> ABO Blood Group System Genotype (Genes) Phenotype (Blood type) Antigens in R.B.C. Natural Antib. In plasma A 1 A 1 , A 1 A 2 A 2 A 2 , A 2 O A 1 (23-25%) A 2 (6-10%) [23%] A 1 , (H) A 2 , (H) anti-B, anti-H Anti-B, anti-A 1 BB, BO B(8-17%) [21%] B,(H) Anti-A/A 1 A 1 B A 2 B A 1 B(3%) A 2 B(1%) [4%] A,A 1 ,B A,B,H Anti-H Anti-A 1 O,O H,h Oh O(43-50%) [52%] Bombay H None Anti-A,-A 1 ,-B Anti-A,-A 1 ,-B,-H

15. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> Universal Donor and Recipient Universal Donor Group O Carries no A or B antigens Packed and processed units have little antibody Universal Recipient Group AB Patient has no anti-A or anti-B present Cannot lyse any transfused cells Beware: other antibodies may be present Using the patient’s own group ASAP will conserve resources

16. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> ABO System & Pregnancy Majorities of hemolytic diseases are due to ABO incompatibility Foetus inherits one gene from each parent. O + O = O, O + A= O or A, O + B= O or B, O + AB= A or B. There is a 20% chance of ABO incompatibility of mother & foetus Only 5% chance of developing hemolytic disease only in type A & B infants of type O mothers , that too only of milder forms

17. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> ABO System & Pregnancy In foetus & newborn, RBCs have a decreased No. of H, A & B reactive sites The foetal immunoglobulin production is low, so the plasma contains very little of anti-A & B agglutinins Anti-A & B produced in the mother being natural are IgM molecules & so do not cross placenta. In some type O adults, much of the anti-A & B and anti-AB (a cross reacting antibody, also called anti-C) isoagglutinins are of IgG class.

18. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> Rhesus Blood Group System First demonstrated by testing human blood with rabbit anti sera against red cells of Rhesus monkey & classifying Rh negative & Rh positive . However the underlying biochemical genetics is not well understood and the genotyping & phenotyping remains little confused The genotype is determined by the inheritance of 3 pairs of closely linked allelic genes situated in tanderm on chromosome 9 & named as D/d, C/c, E/e (Fisher- Race theory)

19. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> Rhesus Blood Group System The gene ‘d’ is an amorph & has no antigenic expression . So there are only five effective antigens. But Weiner postulates a series of allelic genes at a single locus Rho (D), rh (C),rh (E), hr © & hr (e) The updated system of Rosenfield refers these antigens as – Rh1, Rh2, Rh3, Rh4, Rh5 Subsequently less common antigens Cw, Du, Es have been found The foetus inherits one gene from each group as a haplotype such as sets of Cde, cde etc from each parent

20. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> Rhesus Blood Group System 12 sets of combinations & 78 genotypes are possible. Most frequent genotypes are – Cde/cde(33%), Cde/cDe(18%), Cde/cDE(12%) cDE/cde(11%), cde/cde(15%), cdE/cde(1%), Cde/cde(1%) Though several Rh genotypes and phenotypes have been described, for clinical & all practical purposes it is enough to know whether one is Rh POSITIVE or NEGATIVE against anti D sera.

21. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> Rhesus Blood Group System Incidence of Rh negative varies in different races: Mongoloids- nil, Chinese & Japanese- 1-2%, Indians-5%, Africans-5-8%, Causcasians-15-17% & Basques-30-35%. The antigenic determinants form an intrinsic part of the red cell membrane protein structure.

22. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> Rhesus Blood Group System C/c & E/e are weak antigens and impractical to match. ‘ D’ is by far the most immunogenic in the Rh system excepting those that have the natural antibodies. There is a rare type of Rh negative called Rh null which lacks all known Rh antigens. ‘ D’ antigen has no natural antibody while C & E have the corresponding natural antibodies , though weak, also found infrequently.

23. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> Rhesus Blood Group System A single transfusion of + ve blood to a – ve person has a 50% chance of forming anti Rh D antibodies (IgG) Anti Rh antibodies are of three categories- 1st order – saline / bivalent / complete antibodies 2nd order - albumin active / univalent / incomplete antibodies 3rd order – atypical / antiglobulin active / incomplete antibodies

24. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> Alternate symbol to Haplotypes CDe  R 1 = 0.42 Rh1, 2,5 cde  r 2 = 0.39 Rh4,5 cDE  R 2 = 0.14 Rh1,3,4 cDe  R = 0.025 Rh3,4 Cde  r’= 0.01 Rh2,5 cdE  r’’= 0.01 Rh3,4 CDE  R z = 0.0025 Rh1,2,3 CdE  r y = very rare Rh2,3

25. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> R1 & R2 are the most common combination in most part of the world However in Africa cDe (R0) has a frequency of up to 60% In the Eskimos virtually every one is Rh positve. Therefore, Rh HDN is rarely a problem Each individual possesses 2 of these haplotypes & hence there are 36 possible combinations

26. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> Pathogenesis Of Rh Iso-immunisation  Rh Negative Women Man Rh positive (Homo/Hetero)     Fetus   Rh Neg Fetus No problem Rh positive Fetus    Rh+ve R.B.C.s enter Maternal circulation   Mother previously sensitized Secondary immune response   ? Iso-antibody (IgG)  Non sensitized Mother Primary immune response  Fetus  unaffected, 1 st Baby usually escapes. Mother gets sensitised?   Fetus Haemolysis       ?

27. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> Pathogenesis Of Rh Iso-immunisation Chances of T.P.H/F.M.H. are only 5% in 1st trimester but 47% in 3rd trimester, many conditions can increase the risk. Chances of primary sensitization during 1st pregnancy is only 1-2%, but 10 to 15% of patients may become sensitized after delivery. ABO incompatibility and Rh non-responder status may protect. Amount of antibodies that enter the fetal circulation will determine the degree of haemolysis

28. LEWIS AND OTHER BLOOD GROUPS .

29. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> Ags not manufactured by the RBCs Comprised of soluble, body fluid Ags which adsorb onto surface of RBCs Expression of Lewis Ags is under the control of 3 independently inherited sets of alleles: Lele, Sese, Hh Le allele codes for production of L-fucosyltransferase, which adds a fucose to the common precursor substance ABO and Lewis enzymes compete for same substance LEWIS POPULATION FREQUENCIES PHENOTYPES WHITE BLACK Le (a + b - ) 23 22 Le (a - b + ) 65 72 Le (a - b - ) 22 6 Le (a + b + ) * * -------------------------------------------------------- * Less than 1% of the population. Reflects transition from Le (a + b - ) to Le (a - b + ). In newborns, Le(a - b - ) --> Le(a + b - ) --> Le(a - b + ) as genetics allow. The soluble Lewis substances take some time to adsorb to RBCs. LEWIS SYSTEM

30. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> LEWIS Ag LEWIS Ag VARIATIONS Pregnant women often phenotype as Le(a - b - ); revert to usual Lewis type after delivery Loss of Lewis Ag expression on RBCs, caused by abnormal lipid metabolism, also seen in: Cancer Alcoholic cirrhosis Some infections LEWIS ANTIBODIES Produced by Le(a - b - ) people Naturally occurring IgM (usually); cold reacting to thermotolerant Activate complement (may cause in vivo or in vitro RBC hemolysis) Will not cross placenta or cause HDN React better with enzyme treated panel cells

31. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> LEWIS ANTIBODIES : ANTI-Le a Anti-Le a More frequently encountered than anti-Le b Generally IgM; IgG formed by Lewis negative people only after significant exposure to Lewis Ags Most are detected in saline suspension at RT; some require 37 o C and AHG Binds C’; agglutination enhanced by using enzyme treated cells May be neutralized with Lewis positive plasma or saliva ANTI-Le b 2 types of Anti-Le b Anti-Le bL reacts with all Le(a - b + ) cells regardless of ABO type Anti-Le bH reacts with Le(a - b + ) cells of O or A 2 type (probably has specificity for a combination epitope (Le b and H)

32. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> LEWIS ANTIBODIES : ANTI-Le b Weaker reacting than anti-Le a Usually IgM; does not activate C’ readily Produced by Lewis negative people and occasionally by Le (a + b - ) people May be neutralized by plasma Anti-Le b usually found along with Anti-Le a CLINICAL SIGNIFICANCE OF LEWIS SYSTEM No HDN Lewis Ags not yet adsorbed to newborns’ RBC membranes Many Lewis Abs are pentameric IgM Transfusion reactions possible but rare Lewis Ags in donor plasma may neutralize some of the recipient Lewis Abs Lewis Ags on donor cells may disassociate Most recipients with Lewis Abs may receive Lewis positive blood

33. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> DUFFY SYSTEM 2 (or 3) allele system inherited by straightforward Mendelian genetics; alleles are codominant Fy a and Fy b (and Fy); Fy 3 , Fy 4 , Fy 5 , Fy 6 and Fy x are considered rare alleles: Fy a Fy a Fy a Fy b Fy a Fy Fy b Fy b Fy b Fy FyFy DUFFY ANTIGENS Well developed at birth Medium immunogenicity Fy a Fy a people have about 15,000 Fy a sites/RBC; Fy a Fy b have about 7000/cell  dosage effect possible Glycoproteins with variable MW (variable glycation) External molecules ( not transmembrane) Labile Ags Do not store well Destroyed completely by enzyme treatment

34. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> Duffy DUFFY POPULATION FREQUENCIES Phenotype Whites Blacks Chine. Fy (a + b - ) 9 17 Fy (a + b + ) 91 49 Fy (a - b + ) 22 34 Fy (a - b - ) 68 <1 DUFFY ANTIBODIES IgG; react best in AHG phase May bind C’ Enhanced by LISS Nonreactive with enzyme treated cells (enzymes destroy Duffy Ags) May show dosage May be difficult to detect because Duffy Ags are labile In vivo production declines quickly, increasing risk of DHTRs

35. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> DUFFY ANTIBODIES: CLINICAL SIGNIFICANCE Conditions: HDN Immediate hemolytic tranfusion reaction (HTR) Delayed hemolytic transfusion reaction(DHTR) Give Fy(a - b - ) to recipient with Anti-Fy a or Anti-Fy b Malaria connection (FyFy common genotype in blacks; rare in whites)

36. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> KIDD SYSTEM 3 allele system inherited by straightforward Mendelian genetics: Jk a , Jk b , and Jk (rare but seen in Polynesian population) Jk a Jk a Jk a Jk b Jk b Jk b Jk a Jk Jk b Jk JkJk KIDD ANTIGENS Jk a , Jk b , Jk 3 (pan Jk) (Jk is an amorph) 40 kD proteins without carbohydrate Well developed at birth Jk a and Jk b share some epitopes with some bacteria; autoimmune possibilities Weakly immunogenic

37. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> KIDD KIDD POPULATION FREQUENCIES Phenotype Whites Blacks Asian Whites Jk(a + b - ) 57 28 23 Jk(a + b + ) 34 49 50 Jk(a - b + ) 27 23 9 Jk(a - b - ) Rare Rare <1 KIDD ANTIBODIES IgG Abs; require AHG for detection Activate C’ efficiently (some Abs detected only by the C’ they bind - polyspecific AHG) Immune Abs (pregnancy or transfusion) Weakly reactive Abs which can have very serious clinical effects Use LISS, AHG and extra serum to detect Difficult to detect; enhanced reactivity with enzyme treated panel cells Show dosage Anti-Jk a more common than Anti-Jk b

38. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> CLINICAL SIGNIFICANCE OF KIDD ANTIBODIES HDN - infrequent and mild HTR - may be very serious (weak recipient Abs may be missed if panel cells are heterozygous for corresponding Ag) DHTR - Kidd Ab titers tend to diminish quickly; good record keeping helps

39. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> KELL SYSTEM Complex system of antigens, many of which are high (>90% or population) or low (<10%) incidence Ags Allelic antigens K & k Kp a & Kp b & Kp c Js a & Js b At least 19 more Antigens fully formed at birth Antigens not denatured by commonly used enzymes Dithiothreitol (DTT) and ZZAP denature Kell Ags

40. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> KELL PHENOTYPE FREQUENCIES Phenotype White (%) Black (%) K-k+ 91 97 K+k+ 9 4 K+k- 0.2 <0.1 Kp(a+b-) <0.1 Kp(a+b+) 2.3 Rare Kp(a-b+) 98 100 Js(a+b-) 1 Js(a+b+) Rare 19 Js(a-b+ 100 80

41. 12/18/20 ABO & Rh Isoimmunisation - Dr J.A. Olaniyi <number> THANK YOU