Test 3: Other Blood Group Systems Flashcards
What are the naturally occurring carbohydrate blood group systems?
-ABO
-Lewis
-P
-I
(IgM)
What are the immune stimulated protein blood group systems?
-RH
-MNSs (IgM)
-Kell
-Duffy
-Kidd
-Lutheran
What causes unexpected antibodies in a patient?
the patient being “challenged” (exposure to antigens)
What is the most common Lewis phenotype?
Le (a-b+)
72% whites
55% blacks
What is the least common Lewis phenotype?
Le(a+b+)
rare for all populations
How do Lewis antigens get on RBCs?
they are passively absorbed
they are not of erythroid origin
Why do newborns type as Le(a-b-)?
not expressed on cord RBCs
What is diminished on maternal RBCs that will seroconvert after the birth of the baby? ***
Lewis antigens
-mothers will type as Le(a-b-) while pregnant
Where are Lewis antigens found?
all throughout the body: lymphocytes, platelets, tissues (organs),
saliva
Are Lewis antigens affected by enzymes?
no, resist enzymes
Lewis antigen _______ cause HRTs, _______ HDFN.
rarely, never
What are two reasons Lewis antigens never cause HDFN?
-IgM, cannot cross the placenta
-baby will not have antigens
Are Le(a) and Le(b) alleles?
No. (gene says yes or no)
What genes does the Lewis system depend on?
Hh, Se, and Le genes
-le, h, and se do not produce
products
If the Le gene is inherited, ____ substance is produced
Le(a)
What must all be inherited to convert Le(a) to Le(b)?
Le, H, and Se
Le(a+b+) RBCs are rare, except in what population?
Asian populations (10-40%)
Phenotype if Inherit only FUT3 (Lewis gene)?
Le(a+b-)
FUT 1 is ______ gene
FUT 2 is ______ gene
FUT 3 is ______ gene
H
secreter
Lewis
Phenotype if Inherit both FUT3 and FUT2
(Secretor gene)?
Le(a-b+)
True or False?
Lea does not turn into Leb
True
Why is anti-Le(a) not made with Le(a-b+)?
still produces small
amounts of Le(a)
What is significant about lele Se H genes being present, (Le a-b-)?
will make antibodies unless it is a baby
Le(a) —-> seen in secretions
If Lewis b, what do they still have in secretions?
Le a
What immunoglobulin type are Lewis antibodies?
IgM
naturally occuring
What immunoglobulin type are Lewis antibodies?
IgM
naturally occurring
Pregnant women will frequently have Lewis _________ in serum.
antibodies
Are Lewis antibodies clinically significant?
________ compatible RBCs
No
-XM compatible RBC (no antigen testing required)
What phases can Lewis antigens agglutinate at?
can occur at immediate-spin (IS), 37°C, and AHG
Lewis RBCs treated with Enzymes enhance anti-Leb
reactivity and may cause…
hemolysis
Anti-Le(__) binds complement; may cause hemolysis in vitro, especially with enzyme treated cells
a
What is neutralization used for with Lewis antibody?
can confirm the presence or eliminate reactions with Lewis antibody
(add liquid Lewis substance to mask the presence, *this is not done often)
Antigen typing of donors for what antigen type does not have to be done?
What type of antigens do have to be typed on the donor?
IgM
IgG
Where are P1 antigens detected?
In plasma and hydatid cyst fluid*
___________blood group system: P antigen.
Globoside
Globoside blood group collection: _______ and ________ antigens.
Luke (LKE), PX2
High frequency antigens in the P blood group system?
P, P(K), and LKE
True or false, P blood group is effected by enzymes.
False. Resistant to enzymes.
How are the P blood group system antigens synthesized?
By adding sugar to precursor substances
Where are P blood group antigens found?
On RBC membrane and in secretions and other cells and tissues
What population expresses the P1 antigen stronger?
How is it expressed at birth?
blacks
poorly expressed at birth
____ % of people express the P1 antigen.
80
What is the first and second most common phenotype of the P blood system?
-P1 is most common (red cells express P, P1, and P(K)
-P2 second most common (lacks P1 antigen but expresses P and P(K))
What are the possible antibodies for P1? P2?
P1- none
P2- anti-P1 (not clinically significant, IgM, enhanced by enzymes)
What antibody is associated with parasitic infections?
anti-P1
What can anti-P1 be neutralized by?
by P1 substance (from hydatid cyst fluid)
True or false,
anti-P1 is non-RBC stimulated?
true (born with it or just have it)
Anti-P1 is not implicated in _______ and rarely HTRS.
HDFN
What is associated with paroxysmal cold hemoglobinuria?*
Autoanti-P
What may appear in children after a viral infection?
Autoanti-P
a biphasic hemolysin that binds with P1 or P2 cells at low temperatures before the complement is activated
-binds in cold and lyses in hot
IgG (Donath-Landsteiner antibody)
Anti-PP1Pk (aka anti-Tja) appear in what individuals?
individuals with the null phenotype
Why is Anti-PP1Pk (aka anti-Tja) clinically significant? What type of antibody is this
- potential to cause severe HTRs and HDFN, and spontaneous abortions
- IgM and IgG
Anti-PP1Pk (aka anti-Tja):
Binds __________ and causes hemolysis in vitro
complement
although Anti-PP1Pk (aka anti-Tja) is clinically significant, why is it never tested for?
because it is rare
What is done if Worton’s jelly is present?
get two sticks to remove it from the sample
Are I and i antithetical antigens?
no
How do I antigens from?
on the precursor A, B, and H chains of RBCs
I blood group system:
Newborns have ___ antigen. On baby cords.
Adults have ____ antigen. Found on every adult cell.*
i, I
i antigen (linear) converts to I antigen (branched)
as a child matures (about ___ years of age)
2
I antibodies:
Cold-reacting, IgM.
Does it bind compliment?
yes
Are I antibodies clinically significant?
No, it is common
not much, autoanti-I -Low titer
I antibodies are usually what?
Usually autoantibody
(autoanti-I)
Alloanti-I is rare
What can be used to verify that I is an issue when testing?
Use cord cells, if negative, then the patient has anti-I
I antibodies are usually __________.
What is unique about it?
autoanti-I (high-titer)
broad thermal amplitude, common in autoimmune hemolytic anemia
Is alloanti-I rare or common?
rare
-stimulated from exposure from someone else (some people who do not fully convert to I —> may be alloanti)
What is the issue with I antibodies and polyspecific?
Finds anti-I every time
How are I antibody reactions avoided?
by prewarming, and
using anti-IgG instead
of polyspecific AHG*
(starting to stop using this at some places)
What is meant by I antibodies react as compound antibodies?
*Often found as an anti-IH
*Stronger agglutination with
RBCs having many H sites
(O and A2)
What are the diseases associated with autoanti-I?
-Mycoplamsa pneumoniae
-Cold hemagglutinin disease
What are the diseases associated with Anti-i?
-Infectious mononucleosis
-Lymphoproliferative disease
-Cold hemagglutinin disease (occasionally)
-alcoholic cirrhosis
What are alphabetical pairs in the MNS system?
M and N
S and s
MNS system —> chromosome ____.
4
Is the MNSs system clinically significant?
yes
What is the frequency of the phenotype M+N+?
Whites - 50%
Blacks - 44%
What is the frequency of the phenotype S-s+?
Whites - 45%
Blacks - 69%
M and N is coded by….
What is the membrane structure called?
GLYCOPHORIN A
SIALOGLYCOPHORIN A
Does M and N show dosage?
***Yes. Homozygous inheritance enhances agglutination (M+N-) or M- N+)
Is M and N effected by enzymes?
***Yes. Destroyed by enzymes.
Is S and s easily destroyed?
S = usually destroyed
s = usually not destroyed
S, s, and U is coded by…..
Membrane structure is called?
GLYCOPHORIN B
SIALOGLYCOPHORIN B
S has __________; s has ________.
methionine
threonine
True or false:
S, s, and U can be destroyed by some enzymes.
True
Where is the U antigen loacted?
near membrane
What is present when S or s is inherited?
U antigen
ABSENCE OF GLYCOPHORIN B (GPB) WOULD RESULT IN…
S–s–U–
What must be done anytime there is a positive antibody screen?
Coomb’s test***
Anti-M is what immunoglobulin type?
Mostly IgM, IgG
-rarely encountered in HDFN
Variable reactions of Anti-M antibodies depends on what?
reagent pH (like it slightly acidic)
Which would you antigen type for:
Anti-M-
Anti-N-
Anti-S, s, U-
Anti-M- might antigen type
Anti-N- usually antigen type
Anti-S, s, U- have to antigen type
Who are N-like antibodies typically found in?
dialysis patients from
formaldehydesterilized
instruments
What immunoglobulin class are N antibodies?
Mostly IgG, Rare IgM
Is the Kell System (K and k) clinically significant?
Yes
Anti-S, s, and U are clinically significant Ig__ antibodies.
G
What blood group system is similar to the Rh system?
Kell
The 2 major antigens in the Kell system:
K (K1): ____% of the population
K (K2/cellano): ____ of the population
less than 9%
more than 90%
The K and k antigens are ___________.
antithetical
Ture or false:
The Kell antigens are well developed at birth.
True
What antigen is very immunogenic (second to the D antigen) in stimulating antibody production?
K (K1) antigen
What are other Kell antigens?
-analogous to the Rh system: C/c and E/e
-Kp antigens
-Js antigens
Which are low-frequency antigens and which are high-frequency antigens in the Kell system?
*Kpa is a low-frequency antigen (only 2%)
*Kpb is a high-frequency antigen (99.9%)
*Jsa (20% in blacks, 0.1% in Caucasians)
*Jsb is a high-frequency antigen (80% to 100%)
What regents are used on Kell antigens to see if there is an underlying antigen?
sulfhydryl reagents***
What makes Kell antigens sensitive to sulfhydryl reagents?
Kell antigens have disulfide-bonded regions on the glycoproteins***
Lacks all Kell system antigens (K0K0)
K0 or Kell(null) phenotype
As a result of red blood cell (RBC) immune stimulation, K0 individuals can develop…
anti-Ku (Ku is on RBCs
that have Kell antigens)
What kind of blood must be given to Kell(null) people?
Kell(null) blood
K0 or Kell(null) —> _________ expression related Kx antigen.
increased
K(null) is autosomal __________.
recessive
What are the high-incidence Kell alleles? (99% of people)
k, Kp^b, Js^b, KEL 11
What are the low-incidence Kell alleles?
K, Kp^a, Js^a, KEL 17
Set of Kell alleles:
Kel 11 and Kel ____
17
Why is it not usual to test for K antigen before transfusion?
low-incidence (9%) but still
super important ( 3rd immunogenic antigen)
What is the frequency of K- k+?
white- 91%
black- 98%
What is the frequency of K+ k-?
white- 0.2%
black- rare
Kell antibodies:
Immunoglobulin ____
IgG
Kell antibodies agglutinate best in _________ test
IAT
Do Kell antibodies bind compliment?
usually not
Are Kell antibodies associated with hemolytic transfusion reactions
(HTRs) and hemolytic disease of the fetus and newborn (HDFN)?
Yes
Are Kell antibodies effected by enzymes (not reagents*)?
No
What is the most common Kell antibody?
Anti-K (K1)
____ ANTIGEN IS PHENOTYPICALLY RELATED TO THE KELL SYSTEM BUT IS NOT GENETICALLY SIMILAR
K(x)
INDIVIDUALS WHO LACK KX
ANTIGEN MAY DEMONSTRATE
RBC ABNORMALITIES
(______________ PHENOTYPE)
McLeod
McLeod phenotype is seen in….
Males because it is inherited on the X chromosome.
-associated with reduced expression of all Kell antigens
MCLEOD PHENOTYPE IS
ATTRIBUTED TO MCLEOD _________
syndrome
Symptoms of McLeod syndrome?
- RBC ABNORMALITIES
- MUSCULAR AND NEUROLOGIC
DEFECTS - INCREASED CREATINE KINASE
What disease is McLeod syndrome associated with?
CHRONIC
GRANULOMATOUS DISEASE
- IMPAIRED PHAGOCYTOSIS
(WHITE BLOOD CELLS [WBCS] ENGULF BUT CANNOT KILL)
What are the Duffy system alleles?
Fya and Fyb
-codominant alleles
Duffy system:
Most important for transfusion purposes?
Fya and Fyb
Are Duffy antigens well developed at birth?
Yes
Are Duffy antigens effected by enzymes?
Yes, destroyed by enzymes (along with NMS)
Do Duffy antibodies bind compliment?
No
How are Duffy antibodies stimulated?
BY TRANSFUSION OR
PREGNANCY
Do Duffy antibodies cause HDFN? HTRs?
HDFN-not common
IMPLICATED IN ACUTE AND DELAYED HTRS
Are Duffy antibodies effected by enzymes?
Does not react with enzyme treated RBCs
Do Duffy antibodies show dosage?
Yes
Anti-_____ MADE BY FY(A-B-) BUT NOT BY BLACKS WITH THIS PHENOTYPE
ANTI-FY3 –
Is Anti-Fy3 effected by enzymes?
Not destroyed by enzymes
THOSE THAT ARE _______ OR _______ DO NOT MAKE THE FY5 ANTIGEN.
FY(A-B-) OR RH
NULL
Are Fy5 antigens effected by enzymes?
Not destroyed by enzymes
Most African Americans are Fy(_____)
a-b-
What is the advantage of Fy(a-b-)?
Certain malarial parasites (Plasmodium knowlesi and Plasmodium vivax) will not
invade Fy(a–) and Fy(b–) negative cells
____ or ____ acts as a receptor for the merozoite to attach to the RBC
Fy(a) or Fy(b)
The Fy(a–b–) phenotype is found frequently in people from…
west and central Africa,
supporting the theory of selective evolution
What are the clinically significant KIDD system antigens?
JKA, JKB
KIDD prevalence chart
*
The KIDD system is well developed in….
neonates
Do KIDD antibodies cause HDFN?
ONLY RARELY RESPONSIBLE FOR SEVERE HDFN
What are the three antigens in the KIDD system?
JKA, JKB, AND JK3
IN THE UNITED STATES, MOST BLACKS (51.1%) ARE JK(____)
Jk(a+B-)
IN THE UNITED STATES, MOST CAUCASIANS (50.3%) ARE JK(_____)
JK(a+B+)
- JK3 IS PRESENT WHENEVER what is present?
JKA AND JKB ARE PRESENT
KIDD NULL PHENOTYPES: JK(A–B–) USUALLY SEEN IN INDIVIDUALS FROM…
THE FAR EAST OR PACIFIC
ISLANDS (RARE)
KIDD NULL PHENOTYPES: JK(A–B–) may produce what antibody?
anti-JK3
KIDD null phenotype RBCs are resistant to…
2M urea
Two important things to remember about KIDD system?
*shows dosage
*enhanced by enzymes
If someone is ever positive for KIDD antibodies, what must happen?
always get negative blood
What is the cause of the most common delayed severe HTRs?
KIDD antibodies
Do KIDD antibodies bind complement?
May bind complement
-causing intra and extravascular hemolysis
Kidd antibodies are implicated in…
HTRs and HDFN
What usually appears with KIDD antibodies?
other antibodies
What aids the detection of KIDD antibodies?
enzymes, low-ionic strength solution (LISS), and polyethylene glycol (PEG)
KIDD antibodies can become ______________ in a few week or months.
undetectable
Is the Lutheran blood group system expressed on cord blood cells?
weakly expressed
Most Lutheran antigens are ____-incidence antigens.
high
antibodies are rare
What are the primary antigens of the Lutheran system?
Lu(a) and Lu(b)
How is Lu(null) phenotype inherited?
recessively, rare
______ % Lu(a–b+)
_______% Lu(a+b+)
_______% Lu(a+b–)
92.4
7.4
0.2
Is Lutheran effected by enzymes?
No
Anti-Lu(a) is what immunoglobin type?
Anti-Lu(b)?
IgM with some IgG
IgG
Lutheran antibodies:
Which may occur without RBC stimulation?
Anti-Lu(a)
What temperature does anti-Lu(a) react best at?
room temp
Both anti-Lu(a) and anti-Lu(b) show what agglutination pattern?
Mixed-field pattern
Which Lutheran antibody is not clinically significant?
Which Lutheran antibody is associated with transfusion reactions (clinically significant but rare)?
anti-Lu(a)
anti-Lu(b)
What are the three different inheritance types for Lutheran antibodies?
-Dominate type Lu (A- B-)
-Recessive type Lu (a- b-)
-X-Linked inhibitor type
Recessive X-Linked
Inhibitor Type:
X linked inhibitor to
Lutheran due to _______
GATA-1
Anti-Lu3 reacts with…
all RBCs except Lu (a- b-)
Dominate type Lu (A- B-) carries….
trace amounts of Lutheran antigens
Dominate type Lu (A- B-) does not make….
Anti-Lu3***
***Dominate type Lu (A- B-) has reduced expression of…
-CD44
-P1
-I (start making anti-I)
-AnWj
-MER2
-INB
-inherit two rare silent alleles LuLu
-lack Lutheran antigens
Recessive type Lu (a- b-)
A type 1 chain has:
The terminal galactose in a 1-3 linkage to subterminal N-acetylglucosamine.
MN antigens and antibodies are well developed at birth, susceptible to enzymes, and generally __________ reactive.
saline
What autoantibody specificity is found in patients with paroxysmal cold hemoglobinuria?
Anti-P
What is the most common antibody in blood bank after ABO and Rh antibodies?
Anti-K
