ABO BLOOD GROUP

Direct typing/Forward Typing/ Red cell typing

• test used for an unknown antigen in a known antibody of known specificity

• ex: red cell typing

Landsteiner Law

1. antigen determine the blood group

2. The corresponding antibody is never present in serum but the opposite antibody

Blood Type A= Gastric carcinoma

Blood type O= Ulcer

Blood Type B= No associated conditions

What are the associated disease/condition in Blood type A, O and B?

1. forward typing

2. reverse typing

What are the 2 serological typing used in ABO blood group?

2-4 years old

What age does A & B antigens formation

6 months

What age does antibody produce in baby?

1. newborn- since there are no antibodies

2. Previously blood type donor cell

What are the exception for reverse typing

Karl Landsteiner

Who discovered ABO blood group system?

Unknown antibody yusing an antigen of known specificity

What is the being detected in reverse grouping

H antigen

Antigen serves as the precursor structure which A and B antigens are made>

B antigen

What is/are the antigens present in a group B individual?

Anti A and Anti B antibodies

Antibodies present in a group O individual?

ABO BLOOD GROUP

• most important blood group for TRANSFUSION THERAPHY

• 1st human group system

TRUE

TRUE/FALSE: ABO, histo blood group is the only blood group that can perform REVERSE TYPING

ABO BLOOD GROUP

most immunogenic antigen

naturaly occuring antibodies

test used for antigen antibody reactions

REVERSE TYPING

• naturally occuring

• serum/ plasma for antibody detection using known antigen of known specificity

REVERSE TYPING

Determine what serological typing used:

Antigen- red blood cell, antibody= unknown

Forward Typing

Determine what serological typing used:

Antigen- unknown, Antibody= antisera

1. Blood type O

2. Blood type AB

What is the most:

1. abundant in PH

2. Least abundant in PH

ABO ANTIBODIES

• naturally occuring/ expected/ non RBC stimulated produce wihtout pripr exposure to RBC

IgM

What is the predominant immunoglobulin used for ABO ANTIBODIES

ABO ANTIBODIES

• React to room temperature/colder

• produce strong agglutination reaction

• Activate complement

TRUE

TRUE OR FALSE: Most antibodies in cord blood serum are from maternal origin

low titer until it reaches 3-6 month old

Why we didn’t perform reverse typing in infanct

Peaks between 5-10 years of age and decline later in life

ABO antibody production elderly people?

Blood type A,B

The blood type that is universal plasma donor, universal redcell receiver

Blood type O

Blood type that is universal red cell donor but universal plasma receiver

Blood type O

It has anti A, anti B, and anti A,B

1. Ab cannot be seperated

2. IgG in nature in terms of immunoglobulin class

What is the special/ unique feauture of anti A,B

Landsteiner Law

• antigen on RBC determines the blood type

1. What present in antigen determine the blood group

2. The corresponding antibody never present in serum but the opposite antibody

What are the 2 rules of LANDSTEINER LAW

ORh-

What blood type is used when there is Emergency transfusion

ORh-

• No D antigen

• RH antigen found in the redcell

Blood type A,B

Used for emergency transfusion plasma type given?

1. Blood type AB

2. Blood type A

3. Blood type O

4. Blood type B

Determine what blood type used in FORWARD TYPING:

Anti A Anti B

1. + +

2. + -

3. - -

4. - +

1. Blood type O

2. Blood type B

3. Blood type AB

4. Blood type A

Determine what blood type used in REVERSE TYPING:

Anti A Anti B

1. + +

2. + -

3. - -

4. - +

INHERITANCE OF THE ABO BLOOD GROUPS

Individual inherits one ABO gene from each parent and these two genes determine which ABO antigens are present on the RBC membrane

1. H gene(HH or Hh)

2. Se gene(SeS or SeSe)

What are the 2 inheritance beling to ABO blood group

H gene

responsible in formation of red cell surface

Se gene

• for formation of secreations

ABO GENE

Production of A, B , O

sese gene

Do not produce ABO surface and called as NON SECRETOR

Blood type O

• If AO or BO, O gene will never express itself

• Amorph gene

Chromosome 9

Where does ABO genes found?

Autosomal dominant

Determine if Autosomal dominant, recessive or sex linked:

most blood groups

Sex-Linked Dominant

Determine if Autosomal dominant, recessive or sex linked:

Xga blood type (trait goes to the females)

Autosomal recessive

Lutheran blood type (must be homozygous to be expressed)

1. AA, AO

2. BB, BO

3. OO

4. AB

What are the expected Genotypes for:

1. A

2. B

3. O

4. AB

ABO, Hh, and Se

Do not actually code for the production of antigens but produce specific glycosyltransferases that add sugars to the precursor substance

Paragloboside / glycan

Basic precursor material from which A, B, and H antigens originate

Transferases / Glycosyltransferases:

enzymes that transfer the immunodominant sugar

Paragloboside structure:

ultimate precursor

GLUCOSE

• first sugar molecule to attach

• it attaches in a beta 1 → 1 linkage wherein the first carbon of glucose is attached to first carbon of ceramide

D-galactose

attaches in a beta 1 → 4 linkage to glucose

L- lucose

Most antigenic molecule of H antigen

Type 1

A PRECURSOR CHAIN beta 1 → 3 linkage between galactose and

N-acetylglucosamine

• seen usually in SECRETIONS

Type 2

• seen usually in RED BLOOD CELLS

• terminal galactose on the precursor substance is attached to the N-acetylglucosamine in a beta 1 → 4 linkage

TYPE 2

ABH antigens on the RBC are constructed on oligosaccharide chains of a ______ precursor substance.

1.O antigen

2. Bombay

Determine what blood type used in FORWARD TYPING OF BOMBAY OR O GENE:

Anti A Anti B Anti H

1. 0 0 +

2. 0 0 0

1. O antigen

2. bombay antigen

Determine what blood type used in REVERSE TYPING OF BOMBAY OR O GENE:

Anti A Anti B Anti H

1. + + -

2. + + +

H ANTIGEN

Precursor structure on which A and B antigens are made

● Results from the inheritance of the H gene

● Inheritance of FUT 1 H and FUT 2 (Se) genes

H gene

inherited to form ABO antigens on the RBCs

Se gene

inherited to form ABO antigens in secretions

FUT 1 H and FUT 2 (Se) genes

• Influences A and B antigen expression

• Located on chromosome 19

ABH ANTIGENS

Develop early in fetal life

● Expression of A and B antigens on the RBCs

○ Fully developed by 2 to 4 years of age

○ Remains constant throughout life

● Phenotypic expression may vary with

○ Race

○ Genetic interaction

○ Disease states

Immunodominant sugars

• Sugars occupying the terminal positions of the precursor chain

• Conferring blood group specificity

L-fucose

• Sugar responsible for H specificity

• Must be formed for the other sugars to be attached in response to an inherited A and/or B gene

H gene

Present in more than 99.99% of the random population

1. “h”

2. hh

1. ____ is quite rare

2. ____is extremely rare - Does not elicit the production of α-2L-fucosyltransferase

● Bombay phenotype (hh)/ H defficient phenotype

• Inherit ABO genes

• Lacks normal expression of ABH antigens

• Discovered in India

α-3N-acetylgalactosaminyltransferase

A gene: codes for___ Elicits higher concentrations of transferase than the B gene

810,000 to 1,170,000

_____ antigens sites exist on an A₁ adult

H gene (either HH or Hh)

the first gene to act on the paragloboside structure

LECTIN

➤ Use anti-H to detect if you have H antigen

• where anti-H came from

• Has the capacity to agglutinate red cells

• Antibody is the same as agglutinogen because it’s capable of eliciting immune response and agglutination

Ulex europaeus

Lectin sources is?

• oligosaccharides

• N-acetyl-D-galactosamine:

what are the antigens that present in our redcells?

N-acetyl-D-galactosamine:

immunodominant sugar for A specificity

oligosaccharides

(series of short chain sugars) ➤ A antigen

Helix pomatia

Anti-A Sources

Dolichos biflorus

Anti-A1 Sources

Anti-B Sources

Iberis amara

Anti-M Sources

Molucella laevis, Bauhinia purpura

Anti-N Sources

Arachis hypogaea

Anti-T Sources

Salvia sclaera

Anti-Tn Sources

oligosaccharides

series of short chain sugars A antigen

N-acetyl-D-galactosamine:

immunodominant sugar for A specificity

Para Bombay phenotypes

• RBCs either completely lack H antigens or have small amounts of H antigen present

• ○ Mutated FUT1 (H gene) with or without an

  active FUT2 (Se gene) or

  ○ Silenced FUT1 gene with an active FUT2

  gene

• Rare phenotypes

Classical Bombay

Identify whether it is Classical Bombay or Para Bombay:

H antigens on RBC are not expressed?

Para Bombay

Identify whether it is Classical Bombay or Para Bombay:

H antigens on RBC are weakly expressed?

Classical Bombay

Identify whether it is Classical Bombay or Para Bombay:

H antigens in saliva?

Para bombay

Identify whether it is Classical Bombay or Para Bombay:

H antigens in saliva may be present or absent?

Both para bombay and classical bombay

Identify whether it is Classical Bombay or Para Bombay:

Anti H in serum are Present

hh/sese

What are the genotype for Classical Bombay?

(H),SeSe or Sese or sese

Gentoype for Para bombay

Para bombay

enzyme associated with the FUT2 gene (α2FucT2􀕅

produces H, A, and B type 1 antigens in

secretions, including plasma. These type 1

antigens in the plasma may adsorb onto the

RBC membrane.

Mutated FUT1 reduced activity of a2L fucosyltransferase

What is the mutation of parabombay

2-3-N acetylgalactosaminyltransferase:

• Transfers an N-acetyl-D-galactosamine sugar to the H substance. This sugar confers A specificity.

TRUE

TRU/ FALSE: The A gene tends to elicit higher concentrations

of transferase than the B gene, leading to

conversion of nearly all of the H antigen on the

RBCs to A antigen sites.

α-3-D galactosyltransferase

B gene: codes for _____