blood group systems

BLOOD GROUP SYSTEMS

KEM Hospital mumbai

BLOOD GROUP ANTIGENS

Most genes on autosomal chromosomes & follow Mendelian rules of inheritance.

Majority demonstrate co-dominance (heterozygotes express both gene products).

Macro molecular glycoproteins & lipoproteins- potent immunogens.

A,B,D followed by K,Fyª

BLOOD GROUP ANTIBODIES

• Usually IgG or IgM ; rarely IgA.

• Alloantibody:- reacts with foreign Ag not present on patient’s own RBC.

• Autoantibody

• Naturally occurring:- antigenic stimulus unknown

• Immune stimulated

COMPLEMENT SYSTEM

Usually Classical pathway.Intravascular Hemolysis:- Abs against

ABO,rarely other IgM bld grp Abs & IgG Abs of Kidd- terminal membrane attack complex ( C5b6789 ).

Extravascular:- IgG via RE systemAbsence of C:-Phagocytic cells via Fγ

receptor

INTERNATIONAL SOCIETY OF BLOOD TRANSFUSION

Over 700 RBCs Ags are recognized and are organized into 29 blood group systems.

High frequency/ Public Ags:- expressed by most donors

Rare / Private Ags

ABO SYSTEM (ISBT 001)

3 Ags : A,B & H4 Phenotypes A,B,AB & O.Weak phenotypes:- A1 &A2B(A):-Inherited –AD, trace A Ag

expression on grp B RBC.Acquired B:-enzymatic deacetylation of

grp A Ag to form a B-like Ag on RBC,seen in bact infection & Ca.

ABO SYSTEMANTIGEN ON RBC

ANTIBODY IN PLASMA/ SERUM

BLOOD GROUP

A Anti B A

B Anti A B

AB None AB

None Anti A and Anti B

O

BOMBAY BLOOD GROUP

BOMBAY & PARA BOMBAY:- Absence of all ABH Ags, (Oh)phenotype.

Frequency :- 1 in 7600Subgroups of A & AB:-A1,A2,A1B & A2B,

react with anti A1 Lectin or human antiA1.

ABO TYPINGICMR:- blood- agglutination,

saliva- inhibition.

MNS SYSTEM (ISBT 002)Expressed only on RBCs on Glycophorin

A,B &E-major sialomucin.3 phenotypes M,MN & N.3 phenotypes S,Ss & s.Abs against M&N:-naturally occurring IgM.Abs against S,s&U:-IgG,Immune

stimulated,reactive at 37ºC.P.falci adhere via sialic acid to RBC, so

glycophorin deficient persons are resistant

P SYSTEM (ISBT 003)

3 Ags: P, Pk & P1 (glycosphingolipids)P1 only on RBC whereas Pk & P also on

lymphocytes, plasma, uroepithelium, fibroblasts & synovium.

Anti P1:-IgM ,naturally occurring,↑ in hydatid cyst& liver flukes.

Anti P & antiP,P1,Pk:-potent hemolysins, IgM or IgM + IgG3.

BIOLOGICAL ROLE OF P Ag

Pk:- IF-α & MHC II receptor, modulate cell signaling.

P:- cell differentiation & neoplasia.Pk:-marker of apoptosis in germinal centre

of B cells, Burkitt Lymphoma & Lymphocytic leukemia.

Receptor for Parvo B19,shiga toxin ,EHEC,P fimbriae of E.coli,Str suis & P.aeruginosa.

P PHENOTYPES

PHENOTYPE RBC Ag ANTIBOBY

P P1,P,Pk -

P2 Pk,P ANTI P1

P1k P1,Pk ANTI P

P2k Pk ANTI P

p - ANTI P,P1,Pk

(ANTI Tja)

RH SYSTEM (ISBT 004)

RH DEFICIENCY SYNDROME:- lack of all Rh Ags.Also lack Fy5 & LW Ags & markedly reduced S/s & U Ags.

Spheroctes & Stomatocytes.↑osmotic fragility & ↓RBC survivalMild hemolytic anemia.Transfusion difficult.

LUTHERAN (ISBT 005)Luª & Lu b Ags,rare in Indians.Abs not often encountered.High affinity for Laminin.Over expression in ovarian ca &other ca-

tumor cell adhesion n metastasis.Sickle cell dis:-↑Lu on retic & sickle cells-

vaso-occlusive crises.

KELL & KX (ISBT 006 & 019)

Gene on chromosome 7, shares homology with CALLA, ECE-1 & neutral endopeptidases.

Abs:-HTR& HDNMcLeod Syndrome:-absence of XK protein

on RBC, brain, heart & skeletal muscles.Associated chronic granulomatous dis

LEWIS (ISBT 007)Ags :-Leª & Le b, passively adsorbed.Also on plasma,saliva,platelets,

lymphocytes,endothelium & uroepi.Abs:-IgM, naturally occurring.H.pylori binds to Leª, aberrant expression

in GIT & Uroepi - tumor mets. Lewis null:-recurrent vaginal candiasis &

UTI , also at risk for heart diseases.

DUFFY (ISBT 008)Ag on DARC gene (duffy antigen receptor

for chemokines) on RBC, purkinge cell, post capillary venule endothelial cells, renal glomeruli endo cell, vasa recta , thyroid & pul capillaries.

Abs:-HTR & HDN ,IgG ,37ºCDARC ® P.vivax, retic from Fy null-

resistant

KIDD (ISBT 009)Ags:- Jka JkbAbs:-HTR, IgGJk – facilitated transport of urea, maintain

RBC osmotic stability.

DIEGO (ISBT 010)21 Ags , on Anion Exchange protein-1No null phenotype.Gas transport & acid base equilibrium Stability of RBC membrane.

CARTWRIGHT (ISBT 011)

Ags:- Yta & YtbAgs located on enzyme Acetyl

cholinesterase.Abs:-benign, IgG, immune stimulated, may

↓ RBC survival.

XG (ISBT 012)One AG:- Xgª + or – on X chromosome.Higher frequency in women.Specific for RBC.Abs:- naturally occurring or immune

stimulated, IgG.

COLTON (ISBT 015)Ags: Co a & Co b on aquaporin 1Abs:-↓RBC survival, HTR & HDN ,

IgG ,immune stimulated.AQ-1 major water channel on RBC &

kidney.

LANSTEINER WIENER (ISBT 016)

Ags:- LWa & LWb (glycoproteins)Abs:- IgG, benign.LW expression ↑ in sickle cell pts & ↑RBC

senescence.

CHIDO RODGERS (ISBT 017)

10 Ags on C4d fragment of complement.Abs benign.C4 deficiency:-autoimmune dis &

susceptible to bact meningitis.

GERBICH (ISBT 020)7Ags on glycophorin C & D (GYP C&D)Abs:-HTR.Glycophorin anchor membrane to

cytoskeleton.Ge null- marked elliptocytosis.GYP C&D bind influenza virus & P.falci.

CROMER (ISBT 021)13 Ags on DAF CD 55Abs:-HTR, ↓RBC survival, IgG, immune

stimulated.CD55 protects cells from C & is ® uroepi &

intestinal E.coli.Null phenotype-chronic GI dis, protein

losing enteropathy.CD55 absent on PNH III RBC.

KNOOPS (ISBT 022)Complement receptor 1 (CR-1, CD 35)Abs not significant.CR 1binds C3b/C4b immune complexes,

promoting their degradation. Enhances phagocytosis in

Leigonella,Leishmaniasis & mycobacteria.CR-1 binds P.falci with rosette formation.

INDIAN (ISBT 023)Ags:- I & IAbs:-IgM at room temp.Auto Abs to I common & low titre cold

agglutinins.Cold AIHA:-malignancy, infectious

mononucleosis.

OTHER SYSTEMSSCIANNA (ISBT O13)DOMBROCK (ISBT 014)HH (ISBT 018)OK (ISBT 024)RAPH (ISBT 025)JOHN MLTON HAGEN (ISBT 026)GLOBOSIDE (ISBT 028)GIL (ISBT 029)