Karl Landsteiner (1901)
discovered ABO blood group
001
ISBT number of ABO
ABO gene
the gene that encodes for the precursor of an enzyme that adds sugar to precursor substance
chr 9
location of ABO locus
H gene
the formation of this gene serves as the biosynthetic precursor for the formation of A and B antigens
chr 19
location of H locus and secretor locus
H antigen
precursor of the ABO blood group antigens
Secretor gene
the gene for expression of ABH antigens on body fluids
Secretor
Secretor or Non-secretor?
SeSe
Secretor
Secretor or Non-secretor?
Sese
Non-secretor
Secretor or Non-secretor?
sese
L-fucose
immunodominant sugar for H antigen
N-acetyl-D-galactosamine
immunodominant sugar for A antigen
D-galactosamine
immunodominant sugar for B antigen
α-2-L-fucosyltransferase
glycosyltransferase for the production of H antigen
α-3-N-acetylgalactosaminyltransferase
glycosyltransferase for the production of A antigen
α-3-D-galactosaminyltransferase
glycosyltransferase for the production of B antigen
False; Type O
Modified True or False:
If a person is Type AB, the H antigen remains unmodified.
37th day
ABO antigens are formed on the __ day of fetal life.
glycolipids / glycoproteins
Type 2 chain paragloboside
composition of ABO antigens in RBCs
glycolipids / glycoproteins
Type 1 chain paragloboside
composition of ABO antigens in secretions
Trypan blue
dye in Anti-A reagent
Acriflavine yellow
dye in Anti-B reagent
Forward Typing
Detection of ABO antigens
3-6 months
Formation of ABO antibodies begin ___ months after birth.
5-10 years old
ABO antibodies peak production during ___ years old.
IgM, IgG, IgA
Nature of ABO antibodies
IgM
Most predominant nature of ABO antibodies
Reverse Typing
unique lab detection for ABO blood group
Reverse Typing
also called serum typing
A1 cells
Reagent for the detection of Anti-A in serum typing
B cells
Reagent for the detection of Anti-B in serum typing
Type AB
Anti-A | Anti-B | A1 cells | B cells |
---|---|---|---|
4+ | 4+ | 0 | 0 |
Type O
Anti-A | Anti-B | A1 cells | B cells |
---|---|---|---|
0 | 0 | 4+ | 4+ |
O gene
considered as the amorph gene in ABO blood group
Hemagglutination Inhibition
principle of the determination of secretory property
Saliva
specimen for the determination of secretory property
A, B, and O cells
indicator cells
Anti-A, Anti-B, and Anti-H
diluted anti-sera
No agglutination
Positive result, indicating the individual is secretor
Agglutination
Negative result, indicating that the individual is non-secretor
Punnett Square
tool used in the determination of the possible blood type of an offspring
Anti-B
common antibody in A1 and A2 subgroup
A2
A subgroup that possesses Anti-A1
Dolichos biflorus
source of Anti-A1 lectin
Ulex europaeus
source of Anti-H lectin
Maclura aurantiaca
Iberis amara
source of Anti-M lectin
Vicia graminea
source of Anti-N lectin
A3
Ax
Aend
Ael
weak A subgroups that produce Anti-A1
Bombay phenotype
absence of H gene, causing non-expression of ABH antigens
hh
Oh
Hnull
symbols of Bombay phenotype
Anti-A
Anti-B
Anti-A,B
Anti-H
antibodies present in the serum of Bombay blood group
IgM
nature of Anti-H
hh sese
genotype of Classical Bombay
hh Se
genotype of Para-Bombay
Type O
Anti-A | Anti-B | A1 cells | B cells | Anti-H lectin | O cells |
---|---|---|---|---|---|
0 | 0 | 4+ | 4+ | 4+ | 0 |
Bombay (Oh)
Anti-A | Anti-B | A1 cells | B cells | Anti-H lectin | O cells |
---|---|---|---|---|---|
O cells | 0 | 4+ | 4+ | 0 | 4+ |
Type O
ABO blood group most reactive to Anti-H lectin due to greatest concentration of H antigen
Type A1B
ABO blood group least reactive to Anti-H lectin due to lowest concentration of H antigen
Group I ABO Discrepancy
Missing or weakly reactive Ab
Group II ABO Discrepancy
Missing or weakly reactive Ag
Group III ABO Discrepancy
Plasma protein abnormalities
Group IV ABO Discrepancy
Miscellaneous problems
Reverse Typing
problem in Group I ABO Discrepancy
Forward Typing
problem in Group II ABO Discrepancy
Rouleaux Formation
problem seen microscopically in Group III ABO Discrepancy
Forward & Reverse Typing
problem in Group IV ABO Discrepancy
Group I ABO Discrepancy
Conditions related to this ABO Discrepancy:
Newborns, elderly patients
Agammaglobulinemia
Hypogammaglobulinemia
Dilution of ABO antibodies
Group II ABO Discrepancy
Conditions related to this ABO Discrepancy:
Leukemia, Hodgkin’s disease
A/B subgroups
Acquired B phenomenon
Excessive amount of BGSS
Group III ABO Discrepancy
Conditions related to this ABO Discrepancy:
Multiple myeloma
Waldenstrom’s macroglobulinemia
Increased fibrinogen levels
Wharton’s jelly contamination
Group IV ABO Discrepancy
Conditions related to this ABO Discrepancy:
Cold-reactive autoantibodies
Unexpected antibodies
Cis-AB
Group I ABO Discrepancy
Anti-A | Anti-B | A1 cells | B cells | O cells | AC |
---|---|---|---|---|---|
4+ | 0 | 0 | 0 | 0 | 0 |
Extend the incubation time of reverse typing mixture for 15-30 mins. at room temp.
resolution for Group I ABO Discrepancy
Group II ABO Discrepancy
Anti-A | Anti-B | A1 cells | B cells | O cells | AC |
---|---|---|---|---|---|
0 | +/- | 4+ | 0 | 0 | 0 |
Extend the incubation time of forward typing mixture for 15-30 mins. at room temp.
resolution for Group II ABO Discrepancy
Group II ABO Discrepancy - Acquired B phenomenon
Anti-A | Anti-B | A1 cells | B cells | O cells | AC |
---|---|---|---|---|---|
4+ | 2+ | 0 | 4+ | 0 | 0 |
Acidify Anti-B reagent
Secretor studies
Addition of acetic anhydride to Px reds cells
resolution for Acquired B phenomenon
E. coli serotype O86
bacteria related to Acquired B phenomenon due to modification of NAG on A antigen
N-acetyl-D-galactosamine
the sugar modified in Acquired B phenomenon, resulting to a pseudo-B antigen
Group III ABO Discrepancy
Anti-A | Anti-B | A1 cells | B cells | O cells | AC |
---|---|---|---|---|---|
4+ | 4+ | 2+ | 2+ | 2+ | 2+ |
Saline dilution / washing of RBCs
resolution for Group III ABO Discrepancy
Group IV ABO Discrepancy
Anti-A | Anti-B | A1 cells | B cells | O cells | AC |
---|---|---|---|---|---|
2+ | 4+ | 4+ | 2+ | 2+ | 2+ |
Prewarming of test components at 37°C
Addition of sulfhydryl reagents (DTT, 2-ME)
Adsorption of cold-reactive antibodies using RESt
resolution for Group IV ABO Discrepancy
Mycoplasma pneumoniae
bacteria related to Group IV ABO Discrepancy