ABO BLOOD GROUP SYSTEM

1. 001

2. ABO

3. Chromosome 9

4. A, B, AB, O

Give the appropriate answers.

1. ISBT number of ABO Blood group System

2. ISBT name

3. In what chromosome is ABO blood group found?

4. What are the 4 phenotypes?

[TRALI]: Transfusion-related Acute Lung Injury

Most common cause of death from transfusion reactions

1. Whole blood

2. Commercial anti sera

3. Antigen

FORWARD TYPING.

1. What is the sample used?

2. What is the reagent used?

3. What is being detected?

1. Serum

2. Known reagent RBCs - A1 and B cells

3. RBC Suspension (3-5%)/Red cells

4. Antibodies

REVERSE BLOOD TYPING.

1. What is the sample used?

2. What are the reagents used?

3. How are the reagents achieved?

4. What is being detected?

Hemolysis

Transfusion of incompatibe blood will immediately result in?

Human or Clerical Errors

What is the most common cause of ABO Hemolytic Transfusion reaction?

1. Karl Landsteiner (1901)

2. Alfred von Decastello and Adriano Sturli (1902)

3. Emil Von Dungern and Ludwik Hirszfeld (1911)

4. A1, A2, A1B, A2B, B, AB, O

DISCOVERY OF ABO BLOOD GROUP SYSTEM.

1. Discovered human ABO groups.

2. Discovered AB blood group.

3. Divided group A into 2 subgroups - A1 and A2

4. ABO system classified into 7 groups, which are?

1. Anti-A antisera

2. Tryphan blue dye

3. Anti-B antisera

4. Acriflavin dye

1. It is a monoclonal antibody antiserum containing IgM that is colored blue.

2. It contains?

3. A monoclonal antibody antiserum containing IgM that is colored yellow.

4. It contains?

1. O

2. A

3. B

4. AB

Determine the Blood Type using ABO Forward Grouping.

Bacteria and Pollen

What elements in nature are found to be chemically similar to A and B antigens?

Blacks

Asians

Group B (in ABO Blood Group) is found twice as frequently occuring in what race?

Asians

The subgroup A2 is rare in what race?

1. O

2. A

3. B

4. AB

Determine the Blood Type using REVERSE GROUPING.

• Slide method - screening

• Tube method - confirmatory

1. What are the two methods of determining ABO Blood Group?

2. What is their difference?

1. Avidity

2. Specificity

3. Specific agglutination titer

1. It refers to how fast the reaction is.

2. It refers to how the antibodies react with their corresponding antigen.

3. Means it is within the zone of equivalence.

• IgM

• Complement

• Room or Cold temperatures

The ABO antibodies are predominantly (what immunoglobulin) that activate ___ and react at ___ temperatures.

Mother’s (maternal origin)

Most antibodies found in cord blood serum are of whom?

False. It is not valid because the antibodies only represent the ones of maternal origin. Forward grouping on cord blood is the only test that can be performed.

True or False. It is valid to do serum ABO testing for babies 3 to 6 months of age because all antibodies are of IgG maternal antibodes which reflect the antibodies of the infant.

Between 5 to 10 years of age

The peak of antibody production happens when?

1. Absent in the plasma

2. Present in the plasma

LANDSTEINER’S LAW.

1. If an agglutinogen is present on the RBC membrane, the corresponding agglutinin is?

2. If an agglutinogen is absent on the RBC membrane, the corresponding agglutinin is?

2+

Determine the Grade using Tube Method.

Numerous medium-sized clumps with reddish background.

4+

Determine the Grade using Tube Method.

One solid aggregate with clear background.

3+

Determine the Grade using Tube Method.

Several large clumps with clear background.

1+

Determine the Grade using Tube Method.

Numerous small-size clumps with reddish background.

• Trace

• Trace to 2+

Determine the Grade using Tube Method.

• Numerous very small clumps with reddish background

• Microscopic

DONATE — RECEIVE

1. A, AB — A, O

2. B, AB — B, O

3. A, B, O, AB — O

4. AB — AB, O

Determine to whom they can donate and from who they can receive blood.

1. A

2. B

3. O

4. AB

1. O, A, B, AB

2. O, B, A, AB

Frequency of ABO Blood Groups

1. Whites/ Blacks

2. Asians

Natural antibodies

These are naturally occurring antibodies that are present at birth. They do not require the presence of a foreign red blood cell to produce ABO antibodies. It is not a product of exposure.

• ABO antibodies

• IgM

• These are non red blood cell stimulated due to environmental exposure. Also called Immune Antibodies.

• It is mostly composed of?

IgG

This is the predominant antibody in Group O individuals

IgM

This is the predominant antibody in Group A and B individuals

• Anti-A,B

• A, B, and AB cells

• This antibody is found in the serum of Group O individuals.

• Which cells does it react with?

False. It is one antibody.

True or False.

Anti-AB is a mixture of anti-A and anti-B antibodies.

Anti-A

Group O and B individuals have this antibody.

1. Anti-A and Anti-A1

2. A1 antigen (not A2 antigen)

3. A2B subgroup by 22-30% (1-8% in A2)

4. None

ANTI-A ANTIBODY.

1. It can be separated into what components?

2. Anti-A1 agglutinates what antigen?

3. In which subgroup does it occur more?

4. Is there an anti-A2 antibody?

H antigen

The precursor structure on which A and B antigens are made.

A1 gene

This gene very efficiently converts all of H substance to A antigen. Hence, A1 and A1B individuals have Anti-H.

1. IgM cold agglutinin

2. Room temperature

Anti-H Antibody

1. What kind of immunoglobulin/ antibody?

2. Best reacts at what temperature?

Bernstein (1924)

He described that an individual inherits one ABO gene from each parent and that these two genes determine which ABO antigens are present on the RBC membrane.

Co-dominant alelle

Genes are inherited as ___ because there is 1 ABO mother and 1 ABO father.

Amorph

The O gene has no detectable antigen produced in response to its inheritance. It is referred to as?

Use punnett square

How to identify the blood type of the offspring?

Homozygous - AA

Heterozygous - AO

Give examples of homozygous and heterozygous genes.

1. Phenotype

2. Genotype

1. A, B, and O refers to?

2. AA, BO, and OO refers to?

Mendelian Law

The inheritance of genes follows what law?

Bernstein theory

This theory states that there is one locus on a chromosome at which any of three three alleles may be located.

1. 6th week

2. RBC, WBC, platelets; salivary glands, pancreas, kidney, body fluids

3. 37 weeks of gestation

4. 2-4 years

ANTIGENS

1. Appear during what week of fetal life?

2. Can be seen in what cells and tissues?

3. When is it produced?

4. When is it fully expressed?

Chromosome 19

H genes can be seen in which chromosome?

• H gene (chromosome 19)

• Se gene (chromosome 19)

• The presence or absence of the ABH antigens on the RBC membrane is controlled by the?

• The presence or absence of the ABH antigens in secretions is indirectly controlled by the?

H genes - H and h alleles (h is amorph)

Se genes - Se and se alleles (se is amorph)

ABO genes - A, B, and O alleles (O is amorph)

What genes are present in ABO Antigen Genetics?

ABO, Hh, and Se genes

These genes do not code for the production of antigens. Instead, it produce specific glycosyltransferase that add sugars to a basic precursor substance.

1. Glycosyltransferase

2. Paragloboside / glycan

1. A transfer sugar

2. A precursor material where A, B, and H antigens originate

Type 2 precursor

Determine the type of precursor.

The terminal galactose is attached to the N-acetylglucosamine in a beta 1 → 4 linkage.

Type 1 precursor

Determine the type of precursor.

The galactose and N-acetylglucosamine is linked via beta 1 → 3 linkage.

FUT 1 (H)

FUT 2 (Se)

Chromosome 19

The FUT 1 (_) and FUT 2 (_) genes are closely linked and are located in what chromosome?

H gene

This must be inherited to form ABO antigens on the RBCs.

Se gene

This must be inherited to form ABO antigens in secretions.

C) a-2-L-fucosyltransferase

» due this, the immunodominant sugar is L-fucose.

Determine the glycosyltransferase of H gene.

a) a-3-D-galactosyltransferase

b) a-3-N-acetylgalactosaminyltransferase

c) a-2-L-fucosyltransferase

B) a-3-N-acetylgalactosaminyltransferase

» the immunodominant sugar is N-acetyl-o-galactosamine.

Determine the glycosyltransferase of A gene.

a) a-3-D-galactosyltransferase

b) a-3-N-acetylgalactosaminyltransferase

c) a-2-L-fucosyltransferase

A) a-3-D-galactosyltransferase

» the immunodominant sugar is D-galactose.

Determine the glycosyltransferase of B gene.

a) a-3-D-galactosyltransferase

b) a-3-N-acetylgalactosaminyltransferase

c) a-2-L-fucosyltransferase

RBC → Glucose → Galactose → N-acetylglucosamine → Galactose

The precursor substance contains?

Type 2 chains

ABH antigens are derived from what chains?

Type 1 and 2 precursors

Blood group substances in secretion are made from?

At least one FUT 1 (H) genes and two O genes.

Individuals who are blood group O has these genes.

1. a-2-L-fucosyltransferase

2. Oligosaccharide chain on the terminal galactose

3. Type 2 chains

1. H genes elicits the production of this enzyme.

2. It transfers L-fucose to the?

3. What chain type is it involved in?

1. L-fucose

2. Blood Group O

1. This sugar is responsible for the H specificity.

2. This ABO Blood Group has the highest concentration of H antigen.

1. h alelle

2. hh allele

3. Bombay

1. This allele of the H gene is quite rare.

2. This allele of the H gene is extremely rare

3. This refers to a phenotype that lacks normal expression of ABH antigens because of hh genotype.

hh genotype

This H genotype does not elicit production of a-2-L-fucosyltransferase

Transferase

The A gene tends to elicit higher concentrations of what enzyme than B gene?

B enzyme

When both A and B genes are inherited, this enzyme competes more efficiently for the H substance, causing more amount of antigenic site.

Seven

» 6,7 is dominant

» most genes are in exon 7

How many exons does the ABO gene have?

Sese (FUT2) genes

This gene codes for the production of a-2-L-fucosyltransferase that modifies the type 1 precursor substance in secretions to form H substance.

Blood Group Substances

These are soluble antigens (A,B,H) that can be found in secretions.

H and Se genes

ABO Antigens in secretions is controlled by?

1. Secretor

2. Nonsecretor

1. If the Sese or SeSe genotype is inherited, the person is called?

2. If the sese genotype is inherited, the person is called?

Glycoproteins

Group A individual that is a secretor will secrete ____ carrying A and H antigens.

Secretors (Sese or SeSe)

It secretes A,B, or H substances in saliva and other body fluids corresponding to the person's blood type.

1. ABH antigens on RBCs

2. ABH Soluble Substances

3. ABH Antigens on RBCs

4. ABH Soluble Substances

5. ABH Antigens on RBCs

Determine if ABH ANTIGENS ON RBCS or ABH SOLUBLE SUBSTANCES.

1. The enzyme produced by the H gene acts as primarily on type 2 chains.

2. The substances are glycoproteins.

3. Type 2 chain refers to a beta 1 → 4 linkage in which the number one carbon of the galactose is attached to the four carbon of N-acetylglucosamine.

4. Type 1 chain refers to a beta 1 → 3 linkage in which the galactose is attached to the three carbon of N-acetylglucosamine sugar.

5. They can be glycolipids, glycoproteins, or glycosphingolipids.

Silent

The O gene is a ___ allele. It does not alter the structure of the H substance. Hence, it has more H antigen sites.

O → A2 → B → A2B → A1 → A1B

List down the cells from the greatest amount of H antigen to the least amount of H.

Von Dungern

He described two different A antigens based on reactions between group A RBCs and Anti-A and Anti-A1.

1. A2

2. Both A1 and A2

1. Between A1 and A2, who does not react with anti-A1 lectin reagent?

2. Between A1 and A2, who reacts with anti-A reagent (anti-A plus anti A1)?

Lectins

These are seed extracts that agglutinate human cells with some degree of specificity.

1. Dolichos biflorus

2. Bandeiraea simplicifolia/ Griffonia simplicifolia

3. Ulex europaeus

Determine the lectin.

1. A lectin that agglutinates A1 and A1B.

2. A lectin that agglutinates B cells.

3. A lectin that agglutinates O cells and other ABO blood groups depending on the amount of H antigen available.

ABO subgroups

They differ in the amount of antigen present on the RBC membrane.

They are the result of less effective enzymes (not as efficient in converting H antigens to A or B antigens).

A1 and A2

» they both strongly react with anti-A reagent.

What are the subgroups of A?

A subgroups

This subgroup is naturally occuring, IgM, cold reactive that is not clinically significant unless it reacts at 37 degrees celsius.

• It can cause ABO discrepancies in both forward and reversed grouping.

• Can cause crossmatch incompatibilities

• Reacts with anti-A1

1. A2 gene

2. A2 and A2B

1. This gene doesn't convert the H3 & H4 to A very well. Hence, there is few of their antigen sites.

2. These individuals may produce an anti-A1.

A3

These red cells cause mixed field agglutination when polyclonal anti-A or anti-A,B is used. They may contain anti-A1.

Mixed field agglutination

This appears as small agglutinates with a background of unagglutinated RBCs.

• Decreased number of A antigen sites per RBC resulting in weak or no agglutination with anti-A

• Varying degrees of agglutination by anti-A, B

• Increased variability in the detectability of H antigen resulting in strong reactions with anti-H

• Presence or absence of anti-A, in the serum

What are the characteristics of weaker A subgroups?

1. A,end

2. Ax

3. Am

4. Ael

DETERMINE THE A SUBGROUP.

1. Displays weak mixed field agglutination with anti-A and anti-AB. No glycosyltransferase is detected.

2. Do not agglutinate with anti-A but agglutinates with anti-AB. It does not produce anti-A1.

3. Displays weak to no agglutination by anti-A and anti-B. It is inherited as a rare allele and does not produce anti-A1.

4. It is unagglutinated by anti-A and anti-AB reagents. It is a rare gene at ABO locus. Only contains H substance in the saliva.

1. Am and Ay

2. Ael

3. A3, Am, Ay

4. Am

DETERMINE THE A SUBGROUP.

1. Have no anti-A1 reaction.

2. Have some anti-A reaction.

3. Have A,H substance in saliva.

4. Have A transferase in serum.

1. Bel

2. B3

3. B, B3, Bm

4. Bx, Bel

5. Bm, B3

6. Bm

DETERMINE THE B SUBGROUP.

1. It is unagglutinated by Anti-B and Anti-AB. An extremely rare phenotype that is described as unique mutation in the exon 7 of B gene.

2. Displays mixed field agglutination that is the most frequent weak B phenotype.

3. Has B,H substances in the saliva.

4. Has unexpected anti-B (no B glycosyltransferase).

5. Has weak positive B glycosyltransferase

6. More frequent in Japan.

1. OH — anti-A, anti-B, anti-AB

2. Oh — null phenotype, has inheritance of hh

3. Bhende, 1952

4. Other bombay individuals

1. What is true phenotype?

2. What is bombay phenotype?

3. Bombay was found by who in what year?

4. Who can donate blood to bombay individuals?

1. False. They do not have H, A, or B antigen but they are Blood/Cell Group O.

2. True

MODIFIED TRUE OR FALSE.

1. Bombay can have H, A, or B antigen that indicates they are Blood Group O.

2. Bombay RBCs are NOT agglutinated with anti-A, anti-B, or anti-H (no antigens present).

1. False. They do not have H, A, or B antigen but they are Blood/Cell Group O.

2. True

MODIFIED TRUE OR FALSE.

1. Bombay can have H, A, or B antigen that indicates they are Blood Group O.

2. Bombay RBCs are NOT agglutinated with anti-A, anti-B, or anti-H (no antigens present).

1. Bombay

2. True Type O

1. Between True Type O and Bombay, who has antibodies against O cells?

2. Between True Type O and Bombay, who has anti-H antigens?

Parabombay phenotype

• A rare phenotype wherein there is compete lack of H antigen or small amounts of H antigen is present.

• The H antigen is weakly expressed.

1. Hangover

2. Criminality

3. Good teeth

Associtions of blood group specificity with terminologies:

1. (__) for A group

2. (__) for B group

3. (__) for O group