Podcast
Questions and Answers
How does the formation of the H antigen relate to the ABO antigen synthesis pathway?
How does the formation of the H antigen relate to the ABO antigen synthesis pathway?
- The formation of the H antigen is a prerequisite; it is subsequently modified by glycosyltransferases to create A and B antigens. (correct)
- The H antigen is formed by the direct addition of specific sugars by glycosyltransferases encoded by the ABO genes.
- The H antigen and ABO antigens are formed independently through parallel pathways utilizing different precursor substances.
- The H antigen inhibits glycosyltransferases, preventing the formation of A and B antigens.
Which of the following distinguishes Type 2 precursor substances from Type 1 in the context of ABO antigen synthesis?
Which of the following distinguishes Type 2 precursor substances from Type 1 in the context of ABO antigen synthesis?
- The presence of fucose.
- The absence of paragloboside.
- The linkage between terminal galactose and N-acetylglucosamine. (correct)
- The type of glycosyltransferases involved.
What is the role of alpha-2-L-fucosyltransferase in the context of H antigen formation?
What is the role of alpha-2-L-fucosyltransferase in the context of H antigen formation?
- It inhibits the activity of glycosyltransferases.
- It transfers fucose to the second carbon of the terminal galactose. (correct)
- It transfers N-acetylglucosamine to the fucose.
- It transfers galactose to the N-acetylglucosamine.
If a red blood cell lacks the enzyme alpha-2-L-fucosyltransferase, which of the following antigens would be absent?
If a red blood cell lacks the enzyme alpha-2-L-fucosyltransferase, which of the following antigens would be absent?
What is the function of glycosyltransferases in the synthesis of ABO antigens?
What is the function of glycosyltransferases in the synthesis of ABO antigens?
How does the genetic relationship between the H gene and the Se gene influence the expression of H antigen?
How does the genetic relationship between the H gene and the Se gene influence the expression of H antigen?
What is the main function of the enzyme produced by the gene in the context of ABO antigen synthesis?
What is the main function of the enzyme produced by the gene in the context of ABO antigen synthesis?
Which term accurately describes the precursor substance acted upon by glycosyltransferases to form ABO antigens?
Which term accurately describes the precursor substance acted upon by glycosyltransferases to form ABO antigens?
In ABO antigen synthesis, what is the significance of the linkage between the first carbon of fucose and the second carbon of terminal galactose?
In ABO antigen synthesis, what is the significance of the linkage between the first carbon of fucose and the second carbon of terminal galactose?
How would a mutation affecting the Beta 1,4 linkage during Type 2 precursor substance formation most likely impact ABO antigen expression?
How would a mutation affecting the Beta 1,4 linkage during Type 2 precursor substance formation most likely impact ABO antigen expression?
If an individual with genotype AO expresses the A antigen in their red cells, which of the following genetic principles is demonstrated?
If an individual with genotype AO expresses the A antigen in their red cells, which of the following genetic principles is demonstrated?
Glycosyltransferases are crucial in determining ABO blood types because they:
Glycosyltransferases are crucial in determining ABO blood types because they:
How does the anomeric carbon's hydroxyl (OH) group position differentiate alpha and beta sugar forms?
How does the anomeric carbon's hydroxyl (OH) group position differentiate alpha and beta sugar forms?
In the context of ABO blood group antigens, if a terminal galactose molecule is attached to N-acetylglucosamine via a Beta-1,3 linkage, where would you primarily expect to find these structures?
In the context of ABO blood group antigens, if a terminal galactose molecule is attached to N-acetylglucosamine via a Beta-1,3 linkage, where would you primarily expect to find these structures?
What is the role of paragloboside in the synthesis of ABO blood group antigens?
What is the role of paragloboside in the synthesis of ABO blood group antigens?
Consider a scenario where two parents are carriers for a rare genetic disorder, but only one parent expresses the disorder's phenotype. Which of the following inheritance patterns could explain this observation?
Consider a scenario where two parents are carriers for a rare genetic disorder, but only one parent expresses the disorder's phenotype. Which of the following inheritance patterns could explain this observation?
Two parents are heterozygous for two different genes (Aa and Bb). What is the probability that their offspring will inherit at least one dominant allele (A or B)?
Two parents are heterozygous for two different genes (Aa and Bb). What is the probability that their offspring will inherit at least one dominant allele (A or B)?
A researcher is studying a newly discovered enzyme that modifies cell surface glycoproteins. Preliminary data suggest the enzyme adds a unique sugar moiety to paragloboside. Which of the following is the MOST likely outcome of this enzymatic activity?
A researcher is studying a newly discovered enzyme that modifies cell surface glycoproteins. Preliminary data suggest the enzyme adds a unique sugar moiety to paragloboside. Which of the following is the MOST likely outcome of this enzymatic activity?
A patient with the genotype sese and HH will express which of the following?
A patient with the genotype sese and HH will express which of the following?
What is the primary enzymatic action of alpha-2-L-fucosyltransferase in the context of ABH antigen synthesis?
What is the primary enzymatic action of alpha-2-L-fucosyltransferase in the context of ABH antigen synthesis?
In an individual with a functional H gene and a Se gene, what is the fate of Type 1 paragloboside?
In an individual with a functional H gene and a Se gene, what is the fate of Type 1 paragloboside?
How does the Se gene influence the expression of ABH antigens in secretions?
How does the Se gene influence the expression of ABH antigens in secretions?
If an individual inherits only the O gene, how are AB antigens affected?
If an individual inherits only the O gene, how are AB antigens affected?
In a non-secretor individual with the AB genotype, what antigens are expressed in their saliva?
In a non-secretor individual with the AB genotype, what antigens are expressed in their saliva?
How does the beta 1,3 linkage of terminal galactose to the preceding sugar relate to the formation of the H antigen?
How does the beta 1,3 linkage of terminal galactose to the preceding sugar relate to the formation of the H antigen?
An individual with the genotype hh at the H gene locus will phenotypically express which of the following on their red blood cells?
An individual with the genotype hh at the H gene locus will phenotypically express which of the following on their red blood cells?
Which of the following enzymatic activities is directly encoded by the H gene?
Which of the following enzymatic activities is directly encoded by the H gene?
The A allele at the ABO locus directly encodes for which of the following?
The A allele at the ABO locus directly encodes for which of the following?
In the context of ABO blood group antigens, what is the role of paragloboside?
In the context of ABO blood group antigens, what is the role of paragloboside?
For an individual with the genotype AO at the ABO locus and HH at the H locus, what immunodominant sugar will be present on their red blood cells?
For an individual with the genotype AO at the ABO locus and HH at the H locus, what immunodominant sugar will be present on their red blood cells?
How does the inheritance of the hh genotype affect the expression of A and B antigens in an individual who also inherits the A and/or B alleles?
How does the inheritance of the hh genotype affect the expression of A and B antigens in an individual who also inherits the A and/or B alleles?
What is the significance of the immunodominant sugar in the context of ABO blood group antigens?
What is the significance of the immunodominant sugar in the context of ABO blood group antigens?
An individual with the blood group B has the genotype BB or BO. What does this indicate about the B allele?
An individual with the blood group B has the genotype BB or BO. What does this indicate about the B allele?
How does the O allele at the ABO locus differ from the A and B alleles in terms of enzymatic activity?
How does the O allele at the ABO locus differ from the A and B alleles in terms of enzymatic activity?
If a person has one A allele and one B allele, and functional H genes, what is the result?
If a person has one A allele and one B allele, and functional H genes, what is the result?
What is the primary function of Alpha-3-N-acetylgalactosaminyltransferase in the context of ABO blood group antigen synthesis?
What is the primary function of Alpha-3-N-acetylgalactosaminyltransferase in the context of ABO blood group antigen synthesis?
An individual inherits the A gene but lacks the H gene. How does this impact the expression of the A antigen?
An individual inherits the A gene but lacks the H gene. How does this impact the expression of the A antigen?
Which of the following scenarios would prevent the formation of both A and B antigens, regardless of the ABO genotype?
Which of the following scenarios would prevent the formation of both A and B antigens, regardless of the ABO genotype?
What is the direct product of the A gene that contributes to the synthesis of the A antigen?
What is the direct product of the A gene that contributes to the synthesis of the A antigen?
Why is the H gene considered essential for the expression of both A and B antigens?
Why is the H gene considered essential for the expression of both A and B antigens?
How does the presence of the amorph ABO gene (O allele) affect the expression of the A antigen in an individual with the A gene?
How does the presence of the amorph ABO gene (O allele) affect the expression of the A antigen in an individual with the A gene?
In the biochemical pathway of ABO antigen synthesis, what role does paragloboside play?
In the biochemical pathway of ABO antigen synthesis, what role does paragloboside play?
An individual has the genotype AO for the ABO gene. Assuming normal expression of the H gene, what blood type antigens will be present on their red blood cells?
An individual has the genotype AO for the ABO gene. Assuming normal expression of the H gene, what blood type antigens will be present on their red blood cells?
How does the inheritance of the H gene affect individuals who also inherit either the A or B antigen genes?
How does the inheritance of the H gene affect individuals who also inherit either the A or B antigen genes?
Which chromosome is the ABO gene located on?
Which chromosome is the ABO gene located on?
In reverse typing, if a patient's serum shows agglutination with known A cells but not with known B cells, what antibodies are MOST likely present in the patient's serum, and what is the likely ABO blood group?
In reverse typing, if a patient's serum shows agglutination with known A cells but not with known B cells, what antibodies are MOST likely present in the patient's serum, and what is the likely ABO blood group?
A patient's serum exhibits no agglutination with either known A cells or known B cells. What is the MOST probable ABO blood group of this patient, and why?
A patient's serum exhibits no agglutination with either known A cells or known B cells. What is the MOST probable ABO blood group of this patient, and why?
If a reverse typing test shows agglutination with both known A cells and known B cells, which ABO blood group does the patient MOST likely have?
If a reverse typing test shows agglutination with both known A cells and known B cells, which ABO blood group does the patient MOST likely have?
What is the MOST critical difference between forward and reverse blood typing methods?
What is the MOST critical difference between forward and reverse blood typing methods?
In a scenario where red blood cells are mixed with a reagent, and there's observable clumping, what immunological event has occurred?
In a scenario where red blood cells are mixed with a reagent, and there's observable clumping, what immunological event has occurred?
During blood typing, after mixing known cells and rotating the mixture, you observe no visible reaction. What is the MOST appropriate interpretation of this result?
During blood typing, after mixing known cells and rotating the mixture, you observe no visible reaction. What is the MOST appropriate interpretation of this result?
What is the MOST likely cause of a false-positive agglutination reaction in blood typing?
What is the MOST likely cause of a false-positive agglutination reaction in blood typing?
In blood group serology, which of the listed factors is MOST critical to ensure that the obtained agglutination reactions are specific and reliable?
In blood group serology, which of the listed factors is MOST critical to ensure that the obtained agglutination reactions are specific and reliable?
In forward typing, how does a '2+' agglutination reaction typically manifest under microscopic observation?
In forward typing, how does a '2+' agglutination reaction typically manifest under microscopic observation?
What microscopic observation is MOST indicative of a '1+' agglutination reaction?
What microscopic observation is MOST indicative of a '1+' agglutination reaction?
In forward typing, a '0' reaction is observed. What does this imply about the red cells in the sample?
In forward typing, a '0' reaction is observed. What does this imply about the red cells in the sample?
In the gel method of forward and reverse typing, what does the presence of red cells at the bottom of the gel tube signify?
In the gel method of forward and reverse typing, what does the presence of red cells at the bottom of the gel tube signify?
During gel method testing, a layer of red cells is observed at the top of the gel tube. What is the MOST accurate interpretation of this result?
During gel method testing, a layer of red cells is observed at the top of the gel tube. What is the MOST accurate interpretation of this result?
In the context of gel method testing to determine Rh positivity/negativity, what does a layer of red cells forming at the top of the gel tube indicate?
In the context of gel method testing to determine Rh positivity/negativity, what does a layer of red cells forming at the top of the gel tube indicate?
What is the primary advantage of using the gel method in blood typing compared to traditional tube methods?
What is the primary advantage of using the gel method in blood typing compared to traditional tube methods?
In forward typing, if a patient's red cells agglutinate with both anti-A and anti-B reagents, but not with anti-D (Rh), what is the patient's blood type, and what might explain a weaker than expected reaction with one of the antisera?
In forward typing, if a patient's red cells agglutinate with both anti-A and anti-B reagents, but not with anti-D (Rh), what is the patient's blood type, and what might explain a weaker than expected reaction with one of the antisera?
What is the most critical control to run alongside routine forward and reverse blood typing, and why is it essential?
What is the most critical control to run alongside routine forward and reverse blood typing, and why is it essential?
In reverse typing, if a patient's serum agglutinates with A1 cells but not with B cells, what is the MOST likely ABO blood group, and what could explain a discrepancy if forward typing indicates AB?
In reverse typing, if a patient's serum agglutinates with A1 cells but not with B cells, what is the MOST likely ABO blood group, and what could explain a discrepancy if forward typing indicates AB?
A technologist observes a 2+ agglutination in the anti-A forward typing reaction but no agglutination in the anti-B or anti-D reactions. The reverse typing shows agglutination with B cells but not with A1 cells. What is the MOST probable cause of this ABO discrepancy?
A technologist observes a 2+ agglutination in the anti-A forward typing reaction but no agglutination in the anti-B or anti-D reactions. The reverse typing shows agglutination with B cells but not with A1 cells. What is the MOST probable cause of this ABO discrepancy?
During ABO blood typing, the forward type shows no agglutination with anti-A or anti-B, while the reverse type shows agglutination with both A1 and B cells. Assuming no technical errors, which of the following is the MOST likely explanation for these results?
During ABO blood typing, the forward type shows no agglutination with anti-A or anti-B, while the reverse type shows agglutination with both A1 and B cells. Assuming no technical errors, which of the following is the MOST likely explanation for these results?
A patient's red cells strongly agglutinate with anti-D reagent but also show a weak positive reaction (1+) in the autocontrol. What is the MOST likely explanation for this unexpected finding?
A patient's red cells strongly agglutinate with anti-D reagent but also show a weak positive reaction (1+) in the autocontrol. What is the MOST likely explanation for this unexpected finding?
A technologist performs a forward type on a patient sample and observes no agglutination with anti-A, anti-B, or anti-D reagents. The reverse type shows no agglutination with A1 or B cells. What is the MOST probable explanation for these results?
A technologist performs a forward type on a patient sample and observes no agglutination with anti-A, anti-B, or anti-D reagents. The reverse type shows no agglutination with A1 or B cells. What is the MOST probable explanation for these results?
When performing reverse typing, a technologist notices rouleaux formation in both the A1 and B cell reactions. What is the FIRST course of action to resolve this interference?
When performing reverse typing, a technologist notices rouleaux formation in both the A1 and B cell reactions. What is the FIRST course of action to resolve this interference?
In a case of suspected ABO discrepancy, the forward type indicates group A, but the reverse type is inconclusive due to weakly reactive reactions. After performing an antibody screen, the technologist identifies a low-titer anti-A1 antibody in the patient's serum. How does this information resolve the ABO discrepancy?
In a case of suspected ABO discrepancy, the forward type indicates group A, but the reverse type is inconclusive due to weakly reactive reactions. After performing an antibody screen, the technologist identifies a low-titer anti-A1 antibody in the patient's serum. How does this information resolve the ABO discrepancy?
A technologist is manually performing an antibody screen and observes hemolysis in several of the test cells. What is the MOST appropriate next step?
A technologist is manually performing an antibody screen and observes hemolysis in several of the test cells. What is the MOST appropriate next step?
Why is forward typing considered reliable for newborns despite low initial antibody titers?
Why is forward typing considered reliable for newborns despite low initial antibody titers?
What is the expected outcome of ABO blood typing if an individual inherits two amorph ABO genes (OO)?
What is the expected outcome of ABO blood typing if an individual inherits two amorph ABO genes (OO)?
A blood sample strongly agglutinates with both anti-A and anti-B reagents but not with anti-AB. What is the most probable cause of this?
A blood sample strongly agglutinates with both anti-A and anti-B reagents but not with anti-AB. What is the most probable cause of this?
What is the immunological basis for compatibility testing prior to blood transfusions, with respect to forward and reverse typing?
What is the immunological basis for compatibility testing prior to blood transfusions, with respect to forward and reverse typing?
In a scenario where a mother is blood type O and the father is blood type AB, what are the possible blood types of their offspring, and what immunological considerations are crucial?
In a scenario where a mother is blood type O and the father is blood type AB, what are the possible blood types of their offspring, and what immunological considerations are crucial?
In blood banking, how is reverse typing used to confirm the accuracy of forward typing results?
In blood banking, how is reverse typing used to confirm the accuracy of forward typing results?
A patient's red cells agglutinate with anti-A reagent but not with anti-B reagent. Their serum does not agglutinate with A1 cells but does agglutinate with B cells. What is the patient's ABO blood group?
A patient's red cells agglutinate with anti-A reagent but not with anti-B reagent. Their serum does not agglutinate with A1 cells but does agglutinate with B cells. What is the patient's ABO blood group?
In the context of ABO blood typing, what might cause a 'weak' agglutination reaction?
In the context of ABO blood typing, what might cause a 'weak' agglutination reaction?
Predict the ABO blood type of an individual whose red blood cells show no agglutination with either Anti-A or Anti-B antisera, while the serum agglutinates both A and B reagent red cells.
Predict the ABO blood type of an individual whose red blood cells show no agglutination with either Anti-A or Anti-B antisera, while the serum agglutinates both A and B reagent red cells.
If forward typing indicates blood type A and reverse typing is inconclusive due to broadly reactive autoantibodies, what approach is most appropriate to confirm the patient's blood type?
If forward typing indicates blood type A and reverse typing is inconclusive due to broadly reactive autoantibodies, what approach is most appropriate to confirm the patient's blood type?
In a forward typing scenario, if a patient's red cells agglutinate with Anti-B but not with Anti-A, and also agglutinate with Anti-AB, which of the following is the MOST likely explanation, considering potential technical errors?
In a forward typing scenario, if a patient's red cells agglutinate with Anti-B but not with Anti-A, and also agglutinate with Anti-AB, which of the following is the MOST likely explanation, considering potential technical errors?
A technologist performs forward and reverse typing on a patient sample. Forward typing shows agglutination with both Anti-A and Anti-B. Reverse typing shows agglutination with A1 cells but not with B cells. Which of the following is the MOST likely explanation for this discrepancy?
A technologist performs forward and reverse typing on a patient sample. Forward typing shows agglutination with both Anti-A and Anti-B. Reverse typing shows agglutination with A1 cells but not with B cells. Which of the following is the MOST likely explanation for this discrepancy?
When performing reverse typing, a patient's serum fails to agglutinate with both A1 and B cells. Forward typing indicates the patient is AB positive. Which of the following is the MOST probable cause for this discrepancy?
When performing reverse typing, a patient's serum fails to agglutinate with both A1 and B cells. Forward typing indicates the patient is AB positive. Which of the following is the MOST probable cause for this discrepancy?
During routine ABO blood typing, a sample shows weak agglutination (1+) with both Anti-A and Anti-B reagents. The Anti-A,B reagent shows a 2+ agglutination. Reverse typing results are negative with both A1 and B cells. What is the MOST likely cause of this discrepancy?
During routine ABO blood typing, a sample shows weak agglutination (1+) with both Anti-A and Anti-B reagents. The Anti-A,B reagent shows a 2+ agglutination. Reverse typing results are negative with both A1 and B cells. What is the MOST likely cause of this discrepancy?
A patient's red cells strongly agglutinate with anti-A and anti-B antisera. However, the serum agglutinates weakly with A1 cells, strongly with B cells, and not at all with O cells. What is the most likely explanation for these findings?
A patient's red cells strongly agglutinate with anti-A and anti-B antisera. However, the serum agglutinates weakly with A1 cells, strongly with B cells, and not at all with O cells. What is the most likely explanation for these findings?
A technologist observes rouleaux formation when performing forward typing. What is the MOST appropriate next step to ensure accurate ABO typing?
A technologist observes rouleaux formation when performing forward typing. What is the MOST appropriate next step to ensure accurate ABO typing?
What is the MOST important step to resolve a situation where both forward and reverse ABO typing results are not in agreement?
What is the MOST important step to resolve a situation where both forward and reverse ABO typing results are not in agreement?
In ABO blood typing, if a patient's red cells show no agglutination with Anti-A, Anti-B, or Anti-A,B, and the serum shows strong agglutination with both A1 and B cells, which is the MOST likely explanation?
In ABO blood typing, if a patient's red cells show no agglutination with Anti-A, Anti-B, or Anti-A,B, and the serum shows strong agglutination with both A1 and B cells, which is the MOST likely explanation?
A patient's red cells show strong agglutination with Anti-A and Anti-B. The serum shows no agglutination with A1, B, or O cells. What is the MOST likely explanation for this?
A patient's red cells show strong agglutination with Anti-A and Anti-B. The serum shows no agglutination with A1, B, or O cells. What is the MOST likely explanation for this?
During an antibody identification panel, one well shows a strongly positive reaction (4+) at immediate spin (IS), 37°C, and AHG phases. All other wells are negative. The autocontrol is negative. What is the MOST likely explanation of what is happening?
During an antibody identification panel, one well shows a strongly positive reaction (4+) at immediate spin (IS), 37°C, and AHG phases. All other wells are negative. The autocontrol is negative. What is the MOST likely explanation of what is happening?
Flashcards
Heterozygous Genotype
Heterozygous Genotype
Having two different versions (alleles) of a gene.
Phenotype
Phenotype
The observable characteristics or traits of an organism, resulting from the interaction of its genotype with the environment; what is expressed.
Dominant Gene
Dominant Gene
The gene that is outwardly expressed when two different alleles are present.
Glycosyltransferases
Glycosyltransferases
Signup and view all the flashcards
Precursor Substance
Precursor Substance
Signup and view all the flashcards
Paragloboside
Paragloboside
Signup and view all the flashcards
Beta-1,3 Linkage
Beta-1,3 Linkage
Signup and view all the flashcards
Beta Configuration
Beta Configuration
Signup and view all the flashcards
Oligosaccharide Chains
Oligosaccharide Chains
Signup and view all the flashcards
Type 2 Precursor Substance
Type 2 Precursor Substance
Signup and view all the flashcards
H Antigen
H Antigen
Signup and view all the flashcards
Alpha-2-L-fucosyltransferase
Alpha-2-L-fucosyltransferase
Signup and view all the flashcards
Fucose Attachment
Fucose Attachment
Signup and view all the flashcards
Se Gene
Se Gene
Signup and view all the flashcards
Sugar Transfer
Sugar Transfer
Signup and view all the flashcards
H gene function
H gene function
Signup and view all the flashcards
Action of Alpha-2-L-fucosyltransferase
Action of Alpha-2-L-fucosyltransferase
Signup and view all the flashcards
Immunodominant sugar of H antigen
Immunodominant sugar of H antigen
Signup and view all the flashcards
Alleles of the H gene
Alleles of the H gene
Signup and view all the flashcards
hh genotype effect
hh genotype effect
Signup and view all the flashcards
Function of A gene
Function of A gene
Signup and view all the flashcards
Immunodominant sugar of A antigen
Immunodominant sugar of A antigen
Signup and view all the flashcards
Requirement for B antigen expression
Requirement for B antigen expression
Signup and view all the flashcards
Genotypes for B antigen
Genotypes for B antigen
Signup and view all the flashcards
ABO alleles location
ABO alleles location
Signup and view all the flashcards
Chromosome 9
Chromosome 9
Signup and view all the flashcards
ABO Gene Alleles
ABO Gene Alleles
Signup and view all the flashcards
Alpha-3-N-acetylgalactosaminyltransferase production
Alpha-3-N-acetylgalactosaminyltransferase production
Signup and view all the flashcards
N-acetyl-D-galactosamine
N-acetyl-D-galactosamine
Signup and view all the flashcards
Paragloboside conversion
Paragloboside conversion
Signup and view all the flashcards
Lacking the H gene
Lacking the H gene
Signup and view all the flashcards
Alpha-3-N-acetylgalactosaminyltransferase function
Alpha-3-N-acetylgalactosaminyltransferase function
Signup and view all the flashcards
ABO gene location
ABO gene location
Signup and view all the flashcards
Express the A antigen
Express the A antigen
Signup and view all the flashcards
Secretor Gene (Se)
Secretor Gene (Se)
Signup and view all the flashcards
H expression in RBCs
H expression in RBCs
Signup and view all the flashcards
H absence in saliva
H absence in saliva
Signup and view all the flashcards
Type 1 paragloboside and L-fucose
Type 1 paragloboside and L-fucose
Signup and view all the flashcards
H antigen conversion
H antigen conversion
Signup and view all the flashcards
O gene expression
O gene expression
Signup and view all the flashcards
Yellow Bird Reagent
Yellow Bird Reagent
Signup and view all the flashcards
Blue Angel Reagent
Blue Angel Reagent
Signup and view all the flashcards
Reverse Typing
Reverse Typing
Signup and view all the flashcards
Forward Typing
Forward Typing
Signup and view all the flashcards
Agglutination in Forward Typing
Agglutination in Forward Typing
Signup and view all the flashcards
Law of Karl Landsteiner
Law of Karl Landsteiner
Signup and view all the flashcards
Blood Type B Antibodies
Blood Type B Antibodies
Signup and view all the flashcards
Blood Type A Antibodies
Blood Type A Antibodies
Signup and view all the flashcards
Presence of A antigens on the RBCs
Presence of A antigens on the RBCs
Signup and view all the flashcards
Presence of Anti-B.
Presence of Anti-B.
Signup and view all the flashcards
Reverse Typing - Known A Cells Reaction
Reverse Typing - Known A Cells Reaction
Signup and view all the flashcards
Reverse Typing - Known B Cells No Reaction
Reverse Typing - Known B Cells No Reaction
Signup and view all the flashcards
Type O Antibodies
Type O Antibodies
Signup and view all the flashcards
Type B Antibody Profile
Type B Antibody Profile
Signup and view all the flashcards
Type A Antibody Profile
Type A Antibody Profile
Signup and view all the flashcards
Type AB Antibody Profile
Type AB Antibody Profile
Signup and view all the flashcards
Agglutination Significance
Agglutination Significance
Signup and view all the flashcards
Gel Method
Gel Method
Signup and view all the flashcards
Red cells at bottom of gel tube
Red cells at bottom of gel tube
Signup and view all the flashcards
Red cells trapped at the top portion of the gel
Red cells trapped at the top portion of the gel
Signup and view all the flashcards
0 Reaction in Agglutination
0 Reaction in Agglutination
Signup and view all the flashcards
2+ Reaction in Agglutination
2+ Reaction in Agglutination
Signup and view all the flashcards
1+ Reaction in Agglutination
1+ Reaction in Agglutination
Signup and view all the flashcards
Homozygous
Homozygous
Signup and view all the flashcards
Heterozygous
Heterozygous
Signup and view all the flashcards
Anti-AB
Anti-AB
Signup and view all the flashcards
Newborn ABO Antibodies
Newborn ABO Antibodies
Signup and view all the flashcards
Amorph Gene (O)
Amorph Gene (O)
Signup and view all the flashcards
ABO Typing at Birth
ABO Typing at Birth
Signup and view all the flashcards
Forward Typing Reagent
Forward Typing Reagent
Signup and view all the flashcards
Gel Test Principle
Gel Test Principle
Signup and view all the flashcards
Reaction Grading
Reaction Grading
Signup and view all the flashcards
Hemolysis in Testing
Hemolysis in Testing
Signup and view all the flashcards
Forward Typing Procedure (Step)
Forward Typing Procedure (Step)
Signup and view all the flashcards
Auto Control Function
Auto Control Function
Signup and view all the flashcards
Reverse Grouping Procedure
Reverse Grouping Procedure
Signup and view all the flashcards
ABO Discrepancy
ABO Discrepancy
Signup and view all the flashcards
Forward vs. Reverse Typing
Forward vs. Reverse Typing
Signup and view all the flashcards
Study Notes
- Blood group antigens exist as carbohydrates linked to lipids (glycolipids) or proteins (glycoproteins) on red cell membranes.
- Exposure to blood group antigens through transfusion or pregnancy can lead to antibody production against lacking antigens.
- Red cells carry unique sets of antigens, and specific antigens can trigger antibody formation, leading to cell destruction.
Red Cell Composition
- Red cells contain both external and internal proteins.
- Band 3 protein and Diego blood group antigen are linked.
- Glycophorin A and B are the tallest RBC membrane proteins and are linked to MNSS antigens.
- Glycolipids are linked to ABO and Lewis antigens.
- Polypeptides are linked to Rh glycoprotein antigens.
Antigen Inheritance
- Blood group antigen presence relies on inherited genes, causing variations in red cell membrane proteins.
- Antigens are expressed differently based on the red blood cell protein they are included in.
ISBT Blood Group System Assignments
- ABO, MNS, P1PK, RH, Lutheran, Kell, Lewis, Duffy, Kidd, and Diego are blood system names with corresponding ISBT gene names and numbers.
- Cartwright, Xg, Scianna, Dombrock, Colton, Landsteiner-Wiener, Chido/Rodgers, Hh, Kx, Gerbich, Cromer, Knops, Indian, Ok, Raph, JMH, IGNT, Globoside, Gil, and RHAG are also included.
International Society of Blood Transfusion (ISBT)
- ISBT recognizes 36 blood group systems.
- ISBT organizes gene names and numbers due to past inconsistencies in terminology.
- A working committee was created in 1980 to standardize red cell antigen terminology.
- The system aims to provide computer-suitable terminology without replacing existing terms.
Hh and ABO Relationship
- The Hh blood group system is linked to the ABO system due to their special relationship.
- ABO blood group antigens cannot exist without the H gene.
Karl Landsteiner
- Karl Landsteiner discovered the ABO blood groups in 1901.
- His work paved the way for advancements in immunohematology and blood transfusion medicine.
- The ABO forward and reverse blood grouping was first performed by him.
- He determined that blood samples mixed in a pattern based on agglutination after drawing blood from himself and associates.
Landsteiner’s Law
- Healthy individuals possess antibodies to ABO antigens absent from their red cells.
- Individuals with a specific ABO antigen will have antibodies against antigens not present on their red cells.
- A person cannot produce an antibody against their own antigens.
- Type A individuals lack the B antigen, leading to anti-B antibodies, while type B individuals lack the A antigen, leading to anti-A antibodies.
ABO Blood Groups
- O blood group have anti-A and anti-B antibodies.
- AB blood group individuals have neither anti-A nor anti-B antibodies.
- Group A individuals contain A antigens and anti-B antibodies.
- Group B individuals contain B antigens and anti-A antibodies.
Blood Typing
- Blood typing determines an individual's blood group.
Forward Typing
- It determines antigens present on red cells via direct cell typing.
- It uses antisera reagents containing specific antibodies.
- Red blood cells are used for the sample.
- The front type directs cell typing.
Reverse Typing
- It determines antibodies present in plasma via indirect cell typing.
- Identifies antibodies present in patient plasma.
- Plasma or serum is the sample used.
- This is also called back-type
Frequency Distributions of ABO Phenotypes (U.S. Population)
- The majority of all races have type O blood.
- White: A (40%), B (11%), AB (4%), O (45%)
- Black: A (27), B (20%), AB (4%), O (49%)
- Asian: A (28%), B (27%), AB (5%), O (40%)
National Voluntary Blood Services Program (NVBSP)
- Blood Group O is the most common in the Philippines, and the frequency follows O > A > B > AB.
- The majority of the Filipinos are Rh positive, while only ~1% has Rh negative with only 1% being Rh negative.
- Blood Group O individuals are universal donors
- If there are lack of A and B packed red cells, then Group O cells can be transfered.
Inheritance of A, B, and O Antigens
- Discovered by Bernstein in 1924.
- A, B, and O antigens pass following the multiple allele theory that an individual is going to get one ABO gene from each parent.
- The two AB0 genes will determine which ABO antigens are present on the red cell membrane.
- A, B, and O antigens need to be inherited in order to be expressed.
- The genes are located at one locus in chomosome 9.
- A, B, O genes and Hh have interaction of 3 genes at 3 separate loci.
- ABO blood group antigens cannot be expressed in red cells without the Hh gene and the Hh blood group system.
- ABO blood group antigens cannot be expressed in secretion if there is a lack of secretor (Se) gene.
Simple Mendelian Genetics of ABO
- Phenotype A results from either AA (homozygous) or AO (heterozygous) genotypes, with A being dominant over O.
- Phenotypes depend on parental genotypes.
- Genotypes are the genes inherited from parents (e.g., AO for A and O).
- Phenotypes are the antigens expressed in red cells based on dominant genes.
Precursor Substance for ABO Antigens
- Glycosyltransferases are produced instead of antigens by inheritance of the ABO gene.
- Paragloboside is the basic precursor substance which is an oligosaccharide chain attached to a protein or lipid molecule linked to form A, B, and H antigens.
- All made up of oligosaccharide chains
- Paragloboside converts to ABO antigens with specific sugars via glycosyltransferases.
Glycosyltransferases
- Glycosyltransferases are enzymes that transfer sugar molecules to a precursor substance to create ABO antigens.
- This precursor substance is known as paragloboside.
Type 1 Precursor Substance
- Seem mainly secretion, plasma, and body fluids
- Last three molecule of paragloboside: Galactose, N-acetylglucosamine, and Galactose
- Galactose → terminal sugar with a beta-1,3 linkage
- N-acetylglucosamine (GlcNAc), and galactose, beta-1,3 linkage that is is attached to is attached to the previous sugar molecule.
Type 2 Precursor Substance
- They are also found in red cells
- There are terminal galactose and differ on the attachment of terminal sugar galactose to the N-acetylglucosamine sugar using BETA 1,4 LINKAGE. The 1st carbon of terminal galactose is attached to 4th carbon of the N-acetylgiucosaine, Beta-1, 4 linkage.
Formation of H Antigen
- Only antigen found in the H blood group system
- Formation via inheritance of the H gene, closely linked to the Se gene on Chromosome 19.
- The alleles for this are H or h, with h being the recessive allele
- Double does of hh has no epxression of H antigen on the red cells
Alpha-2-L-fucosyltransferase.
- The gene product of that
- Transfers a fucose sugar to the 2nd card of the terminal sugar, aka. galactose
- Is now the immunodominant sugar
Amorph
- If you have inherited a double dose of the amorph allele h gene(hh) there is no secretion, as a result
- Alpha-2-L-fucosyltransferase cannot add fucose to terminal galactose of paragloboside as a result
- All paraglobosides will remain thus conversion to H antigen will NOT occur.
- The first individual to have this phenotype was found in Bombay, India, termed the Bombay phenotype (hh, silent h allele)
Formation of A antigen
- Depends on inheritance of the ABO gene and the presence of the H gene.
- Able to express on their red cell due to AA ( homozygous) or A0 (heterozygous) alleles
- The gene product is: Alpha-3-N-acetylgalactosaminyltransferase that will transferN acetyl-D-galactosamine
- Paragloboside must Be converted to the H antigen before being converted to A antigen
Formation of B antigen
- To express A B antigen, the individual must inherit the B allele
- BB (homozygous) or BO allele
- The gene product of is: Alpha-3-D-galactosyltransferase transfer the galactose sugar to the H antigen
- The paragloboside must be first converted to H antigen that will transfers the fucose
Biochemical Structures
- The only antigen found in the H blood group system
- Formation via inheritance of the H gene, closely linked to the Se gene on Chromosome 19.
- The alleles for this are H or h, with h being the recessive allele
Bombay phenotype (hh, silent h allele)
- Alpha-2-L-fucosyltransferase cannot add fucose to terminal galactose of paragloboside
- Gene product: Alpha-3-N-acetylgalactosaminyltransferase that will transferN acetyl-D-galactosamine
- In order to have the A antigen, an individual must have
-
- Can happen for BB ,or the allele
- Allel is present on chromosome location 9
Secretor Genes
- The inheritance will only allow for the transfer the alpha product ( enzyme ) in the terminal galactose leading to thee H gene
Antigen Location of ABO blood types
- Ranging integral components of different cells with variations in the number of antigen count for different cells
Application
-
ABHH - Able to covert to become H antigen creating all antigens for the respective type, can only be secreted by those with Alpha-2-L-fucosyltransferase
-
AB Hh sese expression is not coded or converted to AB blood type
Se Gene
- Expression will allow for all ABH and A and H creating all antigens for the respective type
Forward typing
- Only contains the identification of reagents being that reagents require red blood cells antibodies
ABO antibodies
- Individuals that the the type are not going produce an antibody against but the antibodies for non ABO groups will still be creating
Determining ABO blood types
- Cross matching is required to ensure the safe transfuction of blood
Forwarded Typing
- The Front type / shift to the right typing can be observed on patients for determining what type antigen is present, it
- Utilizes antisera of reagents or specific antigens to find a match where a sample is used to verify and check against one another
ABO blood Typing
- IgM both activate at room temperature
- The majority Filipinos Are Rh positive, .01 % RH Negative with only 1 percent being so
Type O individual: Anti AB IGG
- Will react both AB antigens despite the reaction
Forward typing
- Is only on newborns due to lack of developed components, should not rely on the mothers contribution
Cause Of Hemolysis
- Complement activations via blood transfusions of the in correct blood result in fatality due to lysis
RECALL
-
Requires forward Typing for the antibodies present on red blood cells
-
Requires reversed typing on the bodies plasma for testing on either A or B antigens
Slides
Color Indicatiors
- Anti A is blue using bromthymol
- Anti B is Yellow using Acriflavine
reversed slides
- are labeled KA known for AA cells and KB known for B cells
Forward typing
-
Slides are homogeneous mixtured
-
Anti A no argulation mean their is no A antigem Anti B there is argulation meanings there is B Present
reversed typing
- Argulation mean the same is present
Tubes
Needs labeling anti A and anti B vertical naming for tube First add reagent the red cell this allos for ez determination and cushion avoiding hemolysis
Tube Grading
Grades
-
+0 negative
-
1+ Small cluster
-
H gene requires a-2-L- fucosyltransferase
-
HARMENING*: -L- fuchose is sugar
Reverse Side
- It needs labeling anti known A cells and KB known B cells,
tube METHOD
- This requires
- Patient plasma
- Test for red blood cells with grading 0 though -4 of reactions,
- If a set 2 grading is present A and B that needs and antibody for there set cells
REmersions
- Requires Samples for forward typing With all known technical and re-genta procedures for testing
Gel Reactions
- Type 1 presence requires the anti body to be present for any agglutination with reactions or the the bottom.
Require Forward typing for A and B antigens and reverse for AA for the A1 BB1 antigens is present
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Explore the H antigen's role in the ABO synthesis pathway, alpha-2-L-fucosyltransferase, and glycosyltransferases. Understand genetic influences of the H and Se genes. Learn about precursor substances and the significance of fucose linkages.
