BB - Day 3

Question 1

Kell low frequency antigen(s)

Answer 1

Kp(a)

Js(a)

-both can be ruled out by single heterozygous crossout

Question 2

Lutheran low frequency antigen(s)

Answer 2

Lu(a)

• also an IgM = clinically insignificant
• can be ruled out by single heterozygous crossout

Question 3

Can M and N antigens be destroyed by enzymes? Can S and s antigens be destroyed by enzymes?

Answer 3

Yes

• sits on outer edge of glycoprotein
• easily destroyed by enzymes

Variable
-antigens further down glycoprotein, less accessible

Question 4

anti-M and anti-N antibodies belong to what class of antibodies? Do they bind complement?

Answer 4

IgM mostly
-cold reactive

Do not bind complement

-clinically insignificant

Question 5

anti-S and anti-s antibodies belong to what class of antibodies? Do they bind complement?

Answer 5

IgG

Yes
-hemolytic transfusion reactions

Question 6

This ANTIGEN varies in strength in adults

Answer 6

P1 antigen

-only antigen in the P group

Question 7

anti-P1 antibodies belong to what class of antibodies?

Answer 7

IgM

-reactive at 4C

Question 8

Does P1 antibody cause HDFN?

Answer 8

No

• IgM antibody, but antigen is poorly developed
• clinically insignificant

Question 9

I blood group - are I and i antigens antithetical? Where can each antigen be found?

Answer 9

No

Babies have little i at birth
-up to 18 months, then decrease

Adults have big I
-trace amounts of little i

Question 10

anti-I antibodies belong to what class of antibodies?

Answer 10

IgM

• cold auto-antibody
• clinically insignificant

Question 11

anti-k (little k) is also called…

Answer 11

Cellano

Question 12

What are the antithetical Kell group antigens?

Answer 12

K and k
Kp(a) and Kp(b)
Js(a) and Js(b)

Question 13

Can Kell be denatured by enzymes?

Answer 13

No - no effect

-reaction strength stays the same

Question 14

This antigen is the second highest in immunogenicity after D antigen

Answer 14

K

• Kell antigens are highly immunogenic
• multiple transfusions increase incidence

Question 15

anti-K antibodies belong to what class of antibodies?

Answer 15

IgG

• AHG by IAT (Coombs)
• clinically significant
• K requires two heterozygous crossouts to rule out

Question 16

Which antigen blood groups can be destroyed by enzymes?

Answer 16

Duffy

M and N
-S and s are variable

Question 17

The antibodies in this antigen group are usually found with another antibody and not by themselves

Answer 17

Duffy

Question 18

anti-Fy(a) and anti-Fy(b) antibodies belong to what class of antibodies?

Answer 18

IgG

• react best at AHG
• saline agglutinins
• clinically significant

Question 19

Which groups of antigens are enhanced by enzymes?

Answer 19

ABO
Rh
Hh
Lewis
Kidd
I
Pi

-mnemonic = “KALIPH Rh” or “Rich Kidd Lewis P. the I”

Question 20

This blood group is notorious for falling below detectable limits

Answer 20

Kidd

-anti-Jk(a) and anti-Jk(b)

Question 21

Which groups of antigens are IgM?

Answer 21

ABO
MN (no S or s)
P1
Ii - I and i
Lewis - Le(a) and Le(b)
Lutheran - Lu(a) only

• mnemonic = “ABOM-N-PILLa”
• IgM = not clinically significant, except ABO

Question 22

Naturally-occurring antibodies include…

Answer 22

anti-A
anti-B
anti-Cw
anti-M
Ii system antibodies
Lewis system antibodies
P system antibodies

-mnemonic = “ABC LIMP”

Question 23

Enzymes have no effect on these antigen groups

Answer 23

Kell

Lutheran

Question 24

anti-Lu(a) antibodies belong to what class of antibodies? anti-Lu(b) antibodies belong to what class of antibodies?

Answer 24

IgM

• clinically insignificant
• room temp

IgG

• clinically significant
• implicated in shortened RBC survival
• 37C

Question 25

This blood system produce soluble antigens. The antigens are not made by RBCs, but rather are made in…

Answer 25

Lewis - Le(a) and Le(b)

• not integral part of RBC membrane
• primarily in secretions and plasma

Tissue

Question 26

During pregnancy, soluble levels of Lewis antigens ___

Answer 26

Decrease

-fluid gain during pregnancy cause dilution

Question 27

Lewis systems depends on these 3 genes to produce Lewis antigen structures

Answer 27

H
Se (secretor)
Le (Lewis)

Question 28

Lewis - what does the Se gene enable to H gene to do?

Answer 28

H gene is a transferase that acts in secretions

Question 29

Does the Le(a) antigen depend on the secretor gene (Se) in order to be made? Why or why not?

Answer 29

No

If Le gene is inherited, Le(a) is made and in secretions regardless of secretor status
-Le(a) adsorbed onto RBCs

Question 30

Does the Le(b) antigen depend on the secretor gene (Se) in order to be made? Why or why not?

Answer 30

Yes - both Se gene and Le gene are needed for Le(b) to be made

Lewis transferase converts converts soluble H to Le(b) antigen
-RBCs adsorb Le(b) instead of Le(a)

Question 31

If a person inherits both le/le genes from their parents, what antigen(s) are present on their RBCs?

Answer 31

Neither Le(a) nor Le(b)

Question 32

Lewis antibodies belong to what class of antibodies?

Answer 32

IgM

-clinically insignificant

Question 33

Antibodies that are clinically significant include the blood groups…

Answer 33

ABO (only IgM group)
Rh
S and s (M and N are not)
Kell
Kidd
Duffy
Lu(b) - Lu(a) is not significant

Question 34

Which blood group systems can trigger complement and cause intravascular hemolysis?

Answer 34

Kidd

Duffy

S and s (M and N do not)

Le(b)

Question 35

Why does Kell (big K) always occur as heterozygous and not by itself as homozygous?

Answer 35

Cellano (small k) is present is almost everyone, so when big K is present, Cellano is present as well, making the person heterozygous