Compare and contrast the antigens and antibodies of the Kell and Duffy blood group systems. Discussthe clinical significance of the antibodies and any other disease associations of each system.
Kell-Ag's- glycoproteins, bounds to Kx proteims via disulfide bonds, making them susceptible to reducing
agents like DTT. They are well expressed at birth and antithetical.
Kell-Ab mostly IgG, require AHG and IAT to ID. Some bind complement, and are assoc. with bacterial
stimulation. Auto-kell -Ab can cause AIHA and Anti- Ku causes Hemolytic transfusion reaction (HTR) and
hemolytic disease of a newborn.
Duffy-Ag are also glycoproteins, that are well expressed at birth. They are assoc. with chemokine and
P.vivax receptors. They display dosage, meaning Anti- Fya reacts better with Fya+b- bc this phenotype
has two Fya alleles. Fya-b- is low incidence but occurs in 68% blacks while Fya+b+ is common in 50%
whites, and Fya+b- occurs in 90% asians
Duffy- Ab Anti-Fy-Abs are IgG and require IAT and AHG to detect, they cause HTR and HDN
To clarify: Kell system antibodies are usually immune IgG antibodies that cause HTR and HDN(anti-K is a very commom alloAb, anti-Ku that you mentioned is very rare alloAb formed by rareKoKo null person). Mention too the McLeod syndrome disease association with the Kell system.Mention that Fya and Fyb antigens are destroyed by ficin and papain enzymes.
Compare and contrast the antigens and antibodies of the MNSs system. Discuss the clinical significanceof the antibodies in this system.
MNS system Ab
Anti-M and anti-N are mostly IgM cold reacting Ab,s and are not clinically significant. Anti-'N', anti-S, andanti-U are IgG reacting at 37 C, require AHG to identify and cause HTR and HDN. Being IgG they are ableto cross the placenta. tThe U antigen is common to all people except Blacks and MN antigen is assocwith Plasmodium Vivax resistance.
Mention that M and N antigens are found on glycoprotein GPA on red cell membrane, S and s(and U) antigens on GPB. M and N antigens are easily destroyed by ficin and papain enzymes, Sand s antigens are variably affected. Mention that anti-M can display marked dosage in antibodyID testing; anti-S and -s sometime shows dosage too. (Correction to your answer- GPAmolecule is a probable receptor for P. falciparum parasite).
Match the antigen with the appropriate characteristic. Each answer can only be used once.
Those who lack this and its antithetical antigen are usually resistant to Plasmodium vivax
Usually only present on cord blood cells
Those who lack this antigen also lack Ss
Most immunogenic after ABO and Rh
The structure that carries this antigenis Glycophorin A
K antigen
U antigen
M antigen
i antigen
U antigen
Fya antigen
Those who lack this and its antithetical antigen are usually resistant to Plasmodium vivax: Fya
Usually only present on cord blood cells: i
Those who lack this antigen also lack Ss: U
Most immunogenic after ABO and Rh: K
The structure that carries this antigen is Glycophorin A: M
Match each disease or situation with the appropriate blood group antibody - each answer can only be used once.
+Cold agglutinin syndrome
+Paroxysmal cold hemoglobinuria
+Show variable reactivity with enzyme-treated RBCs
+Agglutinates are mixed-field and refractile
+Antibody presence may rapidly decrease in vivo
+Common alloantibody. Early HDN.
+Infectious mononucleosis
+Uncommon antibody to high frequency antigen, destroyed by DTT
+Early multiple spontaneous abortions
+Cold-reacting antibody, show dosage
Show variable reactivity with enzyme-treated RBCs: anti-S
Agglutinates are mixed-field and refractile: anti-Sda
Antibody presence may rapidly decrease in vivo: anti-Jka
Common alloantibody. Early HDN.: anti-K
Infectious mononucleosis: anti-i
Uncommon antibody to high frequency antigen, destroyed by DTT: anti-k
Early multiple spontaneous abortions: anti-PP1Pk
Cold-reacting antibody, show dosage: anti-M
In the McLeod syndrome, patients have:
1) Association with Chronic Granulomatous Disease
2) Ancanthocytosis, decreased RBC survival in vivo
3) Increased expresson of Kell antigens
4) 1 and 2 only
1 and 2 only
The Lub antigen is a high-frequency antigen and is found on most red cells. How often would one expect
to find the corresponding antibody?
A) Rarely, because most individuals have the antigen and therefore would not develop the antibody
Antibodies of the Kidd blood group system:
A) React best by the indirect antiglobulin test
A patient is admitted to the hospital. Medical records indicate that the patient has a history of anti-Jka.
When you performed the antibody screen, it was negative. You should:
A) Crossmatch using Jka negative units
Which of the following red cell antigens are found on glycophorin B?
C) S,s
Proteolytic enzyme treatment of red cells usually destroys which antigen?
A) Fya
The glycophorin molecule of the MNSs system is a receptor for which organism?
Plasmodium falciparum
An antibody that sometimes causes hemolysis in lab testing (in vitro) with serum. Reacts with the RBCs of
2 of 10 crossmatched donor units is likely:
B) anti-Lea
The RBCs of a nonsecretor (se/se) will most likely type as:
B) Le(a+b-)
Anti-Lea and anti-Leb appear most often:
D) in the sera of pregnant women
A patient's serum reacted weakly positive with 15 of 16 group O panels cells at AHG. The autocontrolwas neg. Tests with the same ficin-treated panels cells showed no reactivity at AHG. Which antibody ismost likely responsible for these results?
D) anti-Chido
A two or 3- red cell antibody screening test will NOT routinely detect which antibody specificity?
C) anti-Dia
The Fy(a-b-) phenotype is most frequently found in which of the following ethnic groups?
A) Black American
jQuery1101007246955416631562_1483767421001A 50 yr old previously transfused black woman's plasma reacts strongly at 37C AHG with all 10 panel
cells tested. The autocontrol is negative. The plasma reacts similarly with the same enzyme-treated panel.
Which of the following antibodies is most likely?
D) anti-U
A positive Donath-Landsteiner test for a biphasic auto-hemolysin is characteristic for what autoimmunedisorder?
Paroxymal cold hemoglobinuria
Match each blood group system with the appropriate characteristic - each answer can only be used once.
+Null phenotype most often found in black population
+Antigen is destroyed by the sulfhydryl reagents DTT and AET
+Sex linked
+Null phenotype most often found in Polynesian population
+Antigens of very high frequency present on sialoglycoproteins GPC or CPD
Le
Jk
Ge
K
Xg
Null phenotype most often found in black population: Le
Antigen is destroyed by the sulfhydryl reagents DTT and AET: K
Sex linked: Xg
Null phenotype most often found in Polynesian population: Jk
Antigens of very high frequency present on sialoglycoproteins GPC or CPD: Ge
Anti-Sda is strongly suspected if
C) the reaction is mixed-field and the agglutinates are refractile
What disease condition found in males is associated with a decreased expression of Kell antigens onRBCs, abnormal RBC morphology, and hemolytic anemia?
McLeods syndrome is an due to the XK gene and is an X linked reccesive trait that results in decreasedexpression of Kell antigens. This results in a lack of the Kx protein and leads to chronic granulomatousdisease which is a neutophil disoder that causes chronic bacterial infections, also leads to nerve andmuscle abnormalities, and RBC abnormalities.
