Immunohematology chapter 2-7
No
Can you accurately interpret a patient's group AB, D-positive result in ABO and D typing tests using monoclonal antibody reagents without additional testing?
Group O donors are selected because the group O phenotype lacks A and B antigens, and so these red cells do not react with ABO antibodies present in patient or donor serum or plasma.
Commercial antibody screening and panel cells always use group O. What is the reason for this choice?
A
How is the Rh genotype cDe/CDe written in Wiener notation? a. R0R1 b. RyR2 c. RzR2 d. R2R1
B
If the patient has a positive DAT, can you perform a weak D test on the red cells? a. Yes, there will be no interference with the test. b. No, the cells are coated with antibody.
Extravascular hemolysis
In transfusion medicine, what is the name of the process whereby antibodies attached to red cell antigens signal clearance in the liver and spleen?
c
Rhnull red cells have membrane abnormalities that shorten their survival. What is the clinical sign of shortened survival? a. Increased production of stem cells b. Severe liver disease c. Hemolytic anemia of variable severity d. Increased blood pressure
Improper centrifugation
Select a source of a potential false-positive result in antiglobulin testing.
The A2 allele produces the same glycosyltransferase as the A1 allele.
Select the statement that is true regarding group A2 red cells.
Allogeneic
Select the term that describes cells or tissue from a genetically different individual within the same species.
Antiglobulin test
Select the test method that may use a rabbit polyclonal anti-IgG
d
Select the true statement regarding Rh antibodies. a. Are not red cell stimulated b. Cannot cross the placenta c. React best at room temperature d. Usually are IgG
Either B or AB
Situation: A group B recipient requires two units of frozen plasma. Which of the following ABO phenotypes is/are appropriate to select for transfusion?
Potency
The FDA has established minimum standards relating to product quality for use in blood banks and transfusion services before assignment of license to a commercial reagent. What term relates to the strength of the product?
b
The following results were obtained on a donor's blood sample: Anti-A + RBCs 0 Anti-B + RBCs 4+ Anti-D + RBCs 0 Weak D test 0 (Check cells 2+) How will the unit be labeled? .a.Group B, D-positive b. Group B, D-negative c. Group O, D-negative d. Group A, D-positive
phenotype
The patient's red cell _____________ is determined by hemagglutination of red cell antigens using specific antisera.
IgG
What antibodies are best detected at 37° C and can cause immune-mediated destruction of transfused red cells possessing the corresponding antigen?
. Fyb and M
What antigens are destroyed when treated with ficin?
Haplotype
What do the linked HLA genes on each chromosome constitute?
Antigram
What document provides the antigen phenotypes for each donor used in the manufacture of commercially supplied screening and panel cells?
9 units out of 100 A compatible blood unit lacks the antigens. Therefore, multiply the antigen-negative frequencies: D = 0.15, E = 0.70, K = 0.90 0.15 × 0.70 × 0.90 = 0.09 or 9 units out of 100
What is the approximate probability of finding a compatible unit of blood for a D-negative patient with antibodies to E and K, if the frequency of D is 85%, E is 30%, and K is 10%?
Autoantibodies
What is the classification of red cell antibodies produced in response to transfusion and pregnancies?
Fucose
What is the immunodominant sugar for the H antigen?
c
What is the mode of Rh antigen inheritance? a. One single locus and one gene inherited b. Three loci and three genes inherited c. Two loci and two genes inherited d. Conjugated regulated gene
False negatives
What is the potential effect in a tube agglutination result if a red cell suspension with a concentration less than 5% is used?
d
What is the purpose of the Rh control in routine Rh typing? a. Confirms that anti-D is specific for D antigen b Ensures that anti-D is active c. Confirms that patient's serum does not contain anti-D d. Detects polyagglutination or spontaneous agglutination
Ulex europaeus
What lectin possesses the specificity for the H antigen?
Heavy chain
What part of the immunoglobulin molecule distinguishes the isotype?
LISS
What potentiator works by increasing the rate of antibody uptake?
Quality control
What term describes technical procedures to determine whether the analytic testing phase is working properly?
Linkage disequilibrium
What term is defined as the phenomenon of antigens occurring at a different frequency in the population, depending on whether they were inherited by linked or unlinked genes?
Recessive
What type of genetic inheritance trait is expressed by the group O phenotype?
Secondary
What type of immune response occurs within 1 to 3 days of exposure and contains a significant production of memory B cells?
weaker
When Ce is inherited in trans to D gene, what happens to the D antigen expression on the red cell?
AA or AO
When an individual phenotypes as group A, which of the following genotypes may apply?
Ael
Which A subgroup can be detected serologically only after adsorption and elution studies?
Leb, Rga, Cha
Which of the following antigens are derived from plasma rather than constituting an integral part of the red cell membrane?
S, s, U
Which of the following antigens is located on glycophorin B?
Leb
Which of the following antigens is poorly expressed on cord cells?
Antibody bound to antigen
Which of the following is responsible for the activation of the classic pathway of complement?
Siblings
Which of the following is the best source of HLA-compatible platelets?
Fy(a−b+)
Which of the following phenotypes is homozygous?
M+N− M+N− is a homozygote and contains more M antigen than an M+N+ heterozygote.
Which of the following red cell phenotypes would react most strongly with anti-M?
Group A plasma to a group AB recipient
Which of the following situations is most likely to cause an ABO incompatibility if blood is transfused?
Anti-N, -P1, -Leb
Which set of antibodies generally reacts at room temperature or below?
Cannot determine
You have added IgG-sensitized red cells to the negative indirect antiglobulin test result in the antibody screen procedure. You observe no agglutination in the tube. What is the interpretation for this antibody screen?
None
. According to Landsteiner's rule (law), what ABO antibody will be detected in a group AB individual's serum?
Le(a+b−)
A non-secretor will most likely have which of the following phenotypes?
HH, Sese
A patient is expressing soluble forms of H antigens in his secretions. Predict this person's genotype.
1+
After adding antigen and antibody to a test tube, small agglutinates with many unagglutinated cells were observed. How should this reaction be graded?
autologous.
An antigen that originates from the individual is termed: