Quiz 9: Uncommon Blood Groups

ISBT nomenclature for the Xg System is A) 002 B) 006 C) 012 D) 024

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.

Which antigen is expressed on C₄B complement fragments? A) Ch_a B) Kn_a C) Yk_a D) Gy_a

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

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).

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

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

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.

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

The high-incidence Gy^a, Hy, and Jo^a antigens belong to which blood group system? A) Wr B) DI C) DO D) Sc

Knops antigens are present in most populations at a rate of: A) 10% B) 30% C) 60% D) 90%

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.

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

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

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.

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.

Bg antibodies are primarily directed toward antigenic determinants present on: A) white blood cells. B) red blood cells. C) platelets. D) meso cells.

The Wright blood group antigens belong to which blood group system? A) Wr B) DI C) DO D) SC

LW has a phenotypic relationship with the antigen. A) D B) P1 C) M D) Wr^a

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.

What percentage of the female population is Xg(a+)? A) 50% B) 66% C) 89% D) 40%

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

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

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

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.

The Sc1 antigen occurs in approximately what percentage of the random population? A) 100% B) 50% C) 10% D) 35%

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.

Which antigen in the high-incidence series (901) is usually IgM and occasionally causes hemolysis? A) Vel B) JMH C) Lan D) Sd^a

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-)

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

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

Which population is most likely to exhibit the Di(b-) phenotype? A) Central America B) Native Americans C) South America D) All of these

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

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

Which antigen is associated with Dombrock null? A) Gy B) Hy C) Jo D) None of these

Gy(a-) RBCs are also A) Do(a-b-). B) Do(a-b+). C) Do(a+b-). D) Do(a+b+).

Most the antigens in the blood group collections are A) high frequency. B) low frequency. C) Both. D) Neither.

Which of these is the Gerbich null phenotype? A) Gerbich B) Leach C) Yus D) None of these

Low prevalence Gerbich-negative phenotypes include all of these EXCEPT A) An^a B) Ge2 C) Ls^a D) Wb

High prevalence Gerbich-negative phenotypes include all of these EXCEPT A) GEAT B) GEIS C) GEPL D) GETI

Which antigen is denatured by enzymes? A) ABTI B) Cromer C) LW D) All of these

Which antigen is resistant to DTT? A) Chido B) Dombrock C) Knops D) All of these

Which antigen is destroyed by DTT? A) Dombrock B) JMH C) Knops D) All of these

Which antibody is enhanced with enzymes? A) Colton B) Gill C) Forssman D) All of these

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

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.

Which of the following antigens is NOT part of the Rh-Associated Glycoprotein System? A) DCE B) DSLK C) Duclos D) Ola

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

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.

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+.

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.

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.

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.

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.

Anti-Vel antibody is usually: A) IgG B) IgM C) Both D) Neither

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

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.

Haemophilus influenza is able to gain entry in to red blood cells via which antigen? A) Anton B) Emm C) Sid D) Vel

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

Placental tissue will absorb antibodies from which blood group? A) Augustine B) Cromer C) Forssman D) Gerbich

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

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.

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.