BB - Day 3 Flashcards
Kell low frequency antigen(s)
Kp(a)
Js(a)
-both can be ruled out by single heterozygous crossout
Lutheran low frequency antigen(s)
Lu(a)
- also an IgM = clinically insignificant
- can be ruled out by single heterozygous crossout
Can M and N antigens be destroyed by enzymes? Can S and s antigens be destroyed by enzymes?
Yes
- sits on outer edge of glycoprotein
- easily destroyed by enzymes
Variable
-antigens further down glycoprotein, less accessible
anti-M and anti-N antibodies belong to what class of antibodies? Do they bind complement?
IgM mostly
-cold reactive
Do not bind complement
-clinically insignificant
anti-S and anti-s antibodies belong to what class of antibodies? Do they bind complement?
IgG
Yes
-hemolytic transfusion reactions
This ANTIGEN varies in strength in adults
P1 antigen
-only antigen in the P group
anti-P1 antibodies belong to what class of antibodies?
IgM
-reactive at 4C
Does P1 antibody cause HDFN?
No
- IgM antibody, but antigen is poorly developed
- clinically insignificant
I blood group - are I and i antigens antithetical? Where can each antigen be found?
No
Babies have little i at birth
-up to 18 months, then decrease
Adults have big I
-trace amounts of little i
anti-I antibodies belong to what class of antibodies?
IgM
- cold auto-antibody
- clinically insignificant
anti-k (little k) is also called…
Cellano
What are the antithetical Kell group antigens?
K and k
Kp(a) and Kp(b)
Js(a) and Js(b)
Can Kell be denatured by enzymes?
No - no effect
-reaction strength stays the same
This antigen is the second highest in immunogenicity after D antigen
K
- Kell antigens are highly immunogenic
- multiple transfusions increase incidence
anti-K antibodies belong to what class of antibodies?
IgG
- AHG by IAT (Coombs)
- clinically significant
- K requires two heterozygous crossouts to rule out
Which antigen blood groups can be destroyed by enzymes?
Duffy
M and N
-S and s are variable
The antibodies in this antigen group are usually found with another antibody and not by themselves
Duffy
anti-Fy(a) and anti-Fy(b) antibodies belong to what class of antibodies?
IgG
- react best at AHG
- saline agglutinins
- clinically significant
Which groups of antigens are enhanced by enzymes?
ABO Rh Hh Lewis Kidd I Pi
-mnemonic = “KALIPH Rh” or “Rich Kidd Lewis P. the I”
This blood group is notorious for falling below detectable limits
Kidd
-anti-Jk(a) and anti-Jk(b)
Which groups of antigens are IgM?
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
Naturally-occurring antibodies include…
anti-A anti-B anti-Cw anti-M Ii system antibodies Lewis system antibodies P system antibodies
-mnemonic = “ABC LIMP”
Enzymes have no effect on these antigen groups
Kell
Lutheran
anti-Lu(a) antibodies belong to what class of antibodies? anti-Lu(b) antibodies belong to what class of antibodies?
IgM
- clinically insignificant
- room temp
IgG
- clinically significant
- implicated in shortened RBC survival
- 37C
This blood system produce soluble antigens. The antigens are not made by RBCs, but rather are made in…
Lewis - Le(a) and Le(b)
- not integral part of RBC membrane
- primarily in secretions and plasma
Tissue
During pregnancy, soluble levels of Lewis antigens ___
Decrease
-fluid gain during pregnancy cause dilution
Lewis systems depends on these 3 genes to produce Lewis antigen structures
H
Se (secretor)
Le (Lewis)
Lewis - what does the Se gene enable to H gene to do?
H gene is a transferase that acts in secretions
Does the Le(a) antigen depend on the secretor gene (Se) in order to be made? Why or why not?
No
If Le gene is inherited, Le(a) is made and in secretions regardless of secretor status
-Le(a) adsorbed onto RBCs
Does the Le(b) antigen depend on the secretor gene (Se) in order to be made? Why or why not?
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)
If a person inherits both le/le genes from their parents, what antigen(s) are present on their RBCs?
Neither Le(a) nor Le(b)
Lewis antibodies belong to what class of antibodies?
IgM
-clinically insignificant
Antibodies that are clinically significant include the blood groups…
ABO (only IgM group) Rh S and s (M and N are not) Kell Kidd Duffy Lu(b) - Lu(a) is not significant
Which blood group systems can trigger complement and cause intravascular hemolysis?
Kidd
Duffy
S and s (M and N do not)
Le(b)
Why does Kell (big K) always occur as heterozygous and not by itself as homozygous?
Cellano (small k) is present is almost everyone, so when big K is present, Cellano is present as well, making the person heterozygous
