Deck 9: Uncommon Blood Groups

Question 1

Anti-Sc3 will react with which Scianna phenotype?

A) Sc: -1, +2
B) Sc: +1, +2
C) Sc: +1, -2
D) All of the above

Answer 1

D

Question 2

An antibody that reacts in the IAT phase of the antiglobulin test and whose antigen expression is depressed by the In (Lu) gene is:

A) anti-Xg^a.
B) anti-Yt^b .
C) anti-In^b.
D) anti-Sc1.

Answer 2

C

Question 3

The Di^a and Di^b antigens are located on:

A) complement receptor one (CRI).
B) erythrocyte acetylcholinesterase.
C) the anion exchange molecule (AE-1).
D) channel-forming integral protein (CHIP).

Answer 3

C

Question 4

LW has a phenotypic relationship with the antigen.

A) D
B) P1
C) M
D) Wr^a

Question 5

How does complement aid in the identification of alloantibodies masked by anti-Ch^a?

A) C4d in plasma will absorb anti-Ch^a.
B) C3b in serum will absorb anti-Ch^a.
C) C3d in plasma will absorb anti-Ch^a.
D) C4a in plasma will absorb anti-Ch^a.

Question 6

The gene for which blood group antigen is located on the petite arm of the X chromosome?

A) Sc1
B) Xg^a
C) Co^a
D) Do^a

Question 7

Antigens in the CH/RG blood group system are described as:

A) resistant to ficin treatment.
B) antithetical partners.
C) well developed on cord cells.
D) adsorbed onto the red blood cell membrane.

Question 8

The high-incidence Gy^a, Hy, and Jo^a antigens belong to which blood group system?

A) Wr
B) DI
C) DO
D) Sc

Question 9

Anti-Wr^b has been frequently observed in patients:

A) with paroxysmal cold hemoglobinuria.
B) with warm autoimmune hemolytic anemia.
C) taking penicillin.
D) with paroxysmal nocturnal hemoglobinuria.

Question 10

Where might you expect anti-Yt^b to react in antibody screening?

A) Immediate spin phase
B) 37^°C phase
C) IAT phase
D) All of the above

Question 11

Bg antibodies are primarily directed toward antigenic determinants present on:

A) white blood cells.
B) red blood cells.
C) platelets.
D) meso cells.

Question 12

What blood group antigens are involved in the regulation of complement because they are located on decoy accelerating factor?

A) CO
B) DO
C) CROM
D) IN

Question 13

Both anti-Di^a and anti-Di^b are known to:

A) cause severe HDN.
B) bind complement.
C) occur as a result of red blood cell stimulation.
D) react at the 37°C and IgG phases.

Question 14

The Wright blood group antigens belong to which blood group system?

A) Wr
B) DI
C) DO
D) SC

Question 15

The following is true regarding anti-Do^a and anti-Do^b.

A) They are destroyed by enzymes.
B) They are frequently naturally occurring.
C) They are known to cause HTRs.
D) They are known to cause clinical HDN.

Question 16

Knops antigens are present in most populations at a rate of:

A) 10%
B) 30%
C) 60%
D) 90%

Question 17

Which antigen is expressed on C₄B complement fragments?

A) Ch_a
B) Kn_a
C) Yk_a
D) Gy_a

Question 18

Which of the following is true concerning Colton antibodies?

A) Encountered frequently
B) Destroyed by enzymes
C) React at immediate spin
D) Stimulated by red blood cell exposure

Question 19

A plasma inhibition study was performed on a patient whose serum sample reacted +/- on all panel cells at AHG. Three sets of A, B, C tubes were set up according to the following scheme: Tube A had 2 drops of patient serum and 1 drop of Ch(a+) Rg(a-) plasma.
Tube B had 2 drops of patient serum and 1 drop of Ch(a-) Rg(a+) plasma.
Tube C had 2 drops of patient serum and 1 drop of Ch(a+) Rg(a+) plasma.
Screening cells were added in triplicate and incubated for 60 minutes at 37°C. The antiglobulin test was performed. All three A tubes reacted at 2+, and the B and C tubes were negative. What antibody is indicated?

A) Anti-Ch^a
B) Anti-Rg^a
C) Another alloantibody
D) None of the above

Question 20

ISBT nomenclature for the Xg System is

A) 002
B) 006
C) 012
D) 024

Question 21

All of the following are inconsistent with Xg^a antibody characteristics except:

A) reactive at the IAT phase.
B) IgM immunoglobulins.
C) resistant to enzymes.
D) known to cause HTRs.

Question 22

is an antigen in the high-prevalence series (901) that is found in saliva and urine. The corresponding antibody typically reacts at the AHG phase and produces a characteristic refractile, mixed-field reaction.

A) Vel
B) JMH
C) Lan
D) Sd^a

Question 23

Disease associations have linked which Colton phenotype with monosomy-7?

A) Co(a+b-)
B) Co(a+b+)
C) Co(a-b+)
D) Co(a-b-)

Question 24

High prevalence Gerbich-negative phenotypes include all of these EXCEPT

A) GEAT
B) GEIS
C) GEPL
D) GETI

Question 25

The Hu antigen is present in the highest prevalence in which people group?

A) African Americas
B) Native Americans
C) West Africans
D) Southeast Asians

Question 26

Gy(a-) RBCs are also

A) Do(a-b-).
B) Do(a-b+).
C) Do(a+b-).
D) Do(a+b+).

Question 27

Low prevalence Gerbich-negative phenotypes include all of these EXCEPT

A) An^a
B) Ge2
C) Ls^a
D) Wb

Question 28

What percentage of the female population is Xg(a+)?

A) 50%
B) 66%
C) 89%
D) 40%

Question 29

Which statement is true concerning the Cartwright antigens?

A) The Yt^b antigen is a strong immunogen.
B) Cord blood tests as Yt^a negative.
C) The Yt^a is inherited as a dominant allele.
D) Yt^b is a high-frequency antigen.

Question 30

The Sc1 antigen occurs in approximately what percentage of the random population?

A) 100%
B) 50%
C) 10%
D) 35%

Question 31

Which antigen is associated with Dombrock null?

A) Gy
B) Hy
C) Jo
D) None of these

Question 32

The rarely encountered Scianna antibodies react in which phase of the antibody screen?

A) Immediate spin
B) 37°C
C) AHG
D) All of the above

Question 33

Which antigen in the high-incidence series (901) is usually IgM and occasionally causes hemolysis?

A) Vel
B) JMH
C) Lan
D) Sd^a

Question 34

Which population is most likely to exhibit the Di(b-) phenotype?

A) Central America
B) Native Americans
C) South America
D) All of these

Question 35

Which antigen is useful as a genetic marker for Mongolian derivation and anthropologic studies?

A) Yt^a
B) Di^a
C) Sd^a
D) Xg^a

Question 36

Which antibody is viewed to be clinically significant because of its association with HTR and HDN?

A) Anti-Bg^a
B) Anti-Kn^a
C) Anti-Di^b
D) Anti-Ch^a

Question 37

The presence of normal GPA (MNS system) is required for the expression of:

A) Co^a
B) Do^b
C) Wr^b
D) Yt^a

Question 38

What criteria must be met for an antigen to be assigned to a blood group system?

A) Must be a red blood cell antigen
B) Must be assigned to a unique chromosomal locus
C) Must be controlled by a single gene or two closely linked genes
D) All of the above

Question 39

Which of these is the Gerbich null phenotype?

A) Gerbich
B) Leach
C) Yus
D) None of these

Question 40

Most the antigens in the blood group collections are

A) high frequency.
B) low frequency.
C) Both.
D) Neither.

Question 41

Placental tissue will absorb antibodies from which blood group?

A) Augustine
B) Cromer
C) Forssman
D) Gerbich

Question 42

Why are the antibodies to the COST collection antigens difficult to identify?

A) The COST antigens are located on carried on the same CR1 receptor as Knop antigens.
B) The COST antigens are only expressed on cord blood cells.
C) The COST antigens are expressed with a high degree of variability.
D) The COST antigens are present in a very low frequency in most populations.

Question 43

Haemophilus influenza is able to gain entry in to red blood cells via which antigen?

A) Anton
B) Emm
C) Sid
D) Vel

Question 44

Anti-Vel antibody is usually:

A) IgG
B) IgM
C) Both
D) Neither

Question 45

Anti-Vel is able to cause:

A) in vitro but not in vivo hemolysis.
B) in vivo but not in vitro hemolysis.
C) both in vitro and in vivo hemolysis.
D) neither in vitro nor in vivo hemolysis.

Question 46

Anti-JMH is found mostly in patients who:

A) lack the JMH protein from birth.
B) form the antibody early in life
C) lost the JMH antigen later in life.
D) show autoimmune RBC destruction.

Question 47

Anti-Indian is able to cause:

A) hemolytic transfusion reactions.
B) hemolytic disease of the fetus and newborn.
C) both of these
D) neither of these.

Question 48

Cromer system antibodies:

A) are usually IgG.
B) do not cause HDFN.
C) are expressed on placentas.
D) are all of these.

Question 49

Which of the following is a characteristic of the Rh-associated glycoprotein (RhAG) ?

A) RhAG does not have Rh blood group antigens.
B) RhAG is present in a complex with the Rh proteins.
C) RhAG is essential for Rh antigen expression.
D) These are all characteristics of RhAG.

Question 50

Anti-Vel is able to cause:

A) severe immediate hemolytic transfusion reactions.
B) hemolytic disease of the fetus and newborn.
C) both of these
D) neither of these

Question 51

Which of the following antigens is NOT part of the Rh-Associated Glycoprotein System?

A) DCE
B) DSLK
C) Duclos
D) Ola

Question 52

Which antigen is resistant to DTT?

A) Chido
B) Dombrock
C) Knops
D) All of these

Question 53

In testing blood cells for the Knops antigen, which would most likely be positive?

A) Cord blood
B) Fresh units from Caucasians
C) Fresh units from West Africans
D) Older units from any population

Question 54

Which statements are true of Anti-Lan?

A) Anti-Lan is formed during transfusion or pregnancy.
B) Anti-Lan is naturally occurring IgM antibodies.
C) Transfusion reactions are rarely caused by Anti-Lan.
D) Severe HDFN can occur because of Anti-Lan.

Question 55

Which antibody is enhanced with enzymes?

A) Colton
B) Gill
C) Forssman
D) All of these

Question 56

Which antigen is denatured by enzymes?

A) ABTI
B) Cromer
C) LW
D) All of these

Question 57

End-stage renal disease may be present in persons with alloanti-MER2 because:

A) MER2- persons who have MER2 on cells other than RBCs will make alloanti-MER2.
B) MER2 is essential for assembly of basement membranes in the kidneys.
C) persons who have made anti-MER2 do not exhibit CD151 mutations.
D) persons who have made alloanti-MER2 are MER2+.

Question 58

Which antigen is destroyed by DTT?

A) Dombrock
B) JMH
C) Knops
D) All of these

Question 59

Why was the Forssman system originally thought to be an A subgroup?

A) Cross-reactivity with monoclonal anti-A1
B) Cross-reactivity with monoclonal anti-A2
C) Cross-reactivity with polycolonal anti-A
D) No cross-reactivity with polycolonal anti-A

Question 60

Anti-Lan is able to cause

A) Severe hemolytic transfusion reactions.
B) Hemolytic disease of the fetus and newborn.
C) Both of these
D) Neither of these.

Question 61

How does Anti-LW usually react?

A) Weakly with D+ RBCs
B) Strongly with D- RBCs from adults
C) Weakly with D- RBCs from cord blood
D) Negatively with Rhnull RBCs

Question 62

Cord blood can be used to differentiate anti-LW and anti-D antibodies because:

A) anti-LW reacts equally well with cord RBCs regardless of their D type.
B) anti-LW reacts only with D+ cord blood and not D- cord blood.
C) anti-LW reacts only with D- cord blood and not with D+ cord blood.
D) anti-LW reacts only with adult cells and not with cord blood.

Question 63

Which statement describes the role of Knops (CR1) in immunity?

A) CR1 binds the complement component fragments C3b and C4b.
B) CR1 functions as a receptor for several pathogenic organisms.
C) CR1 processes immune complexes for transportation to the liver and spleen.
D) CR1 performs all these roles.