119 terms

Blood Bank Lectures 10-15

Lewis System
antigens are manufactured by tissue cells, secreted into the body fluids, and are absorbed (stuck) onto the RBC membrane.
To have Lewis antigens these genes must be present
Lewis genes AND the secretor (Se) gene
3 ways Lewis antigens differ
1. Lewis antigens are not intrinsic to the RBC membrane produced during the cell development.
Antigens are produced by tissue cells and are absorpted onto the RBCs.
2. A person's Lewis phenotype is NOT determined SOLELY by genes at the Lele locus.
Hh and Sese loci are involved with the Lele locus
3. The amount of Lewis antigen expression on the RBC varies according to the cell's ABO phenotype.
What Chromosome is the Le gene on?
Short arm of chromosome 19
(90% white population)
Genes needed to express Le-a
Just Le gene
Genes needed to express Le-b
Le and Se genes
Le-a %
22% of the population
72% of the population
Le-b secretes what antigens and what antigens are on the RBC
both Lea and Leb soluble antigens are present in the secretions and plasma but only Leb appears on the RBC surface.
LE (a-b-)
no Le antigens are present on the RBC or secretions...
(nonfunctional or partially active Lewis transferase)
A baby that is genetically Le(a-b+)
At birth:
2 months:
12-18 months:
Finally (6 - 7 years):
"The Scandal in the Lewis Family":
Lea (Lea), age 22, married a bum named Bob (Leb), who is 50 years her senior (72)
Anti Lewis andtibodies
Generally produced by Le(a-b-) persons
Generally IgM and can't cross the placenta
A cold LeMN PHI
Lewis, Lu-a, anti-M, anti-N, anti-S, anti-P, Anti-P1, Anti-Pk, Luke (LKE), Anti-H, Anti-I, anti-i
Lewis antibodies
Generally considered insignificant in blood transfusion (because they can fall off)
Helicobacter pylori
Expresses Lewis antigens.
Globoside antigens
All P but P1 (P, Pk, and LKE)
Rare P phenotypes
p, P1k, and P2k.
Most common P phenotypes
P1 and P2
Very Rare P Phenotype
The P1 antigen
is present on the RBCs of 80% of the population
Similar to the 80% A1 and 20% A2 in the ABO System
Approximately 20%
lack the P1 antigen and are designated as P2
Similar to the 80% A1 and 20% A2 in the ABO System
P1 Antigen
deteriorates rapidly on storage
Donath-Landsteiner antibody.
IgG auto-anti-P antibody
Biphasic Hemolysin
Paroxysmal Cold Hemoglobinuria (PCH)
diagnosed by the Donath-Landsteiner Test
P antigen serves as a receptor for what virus
parvovirus B19, which causes erytherma infectiosum (Fifth's Disease).
people who are little p are naturally resistant.
Anti-PP1Pk Antibody
Also known as the anti-Tja Antibody
Seen in very rare "p" people who lack ALL of the P blood group system's antigens (P, P1, & Pk)
Ii system
all babies are born with the i then as they age they can be converted to I (IF the person is I phenotype)
Auto Anti-I
Common autoantibody that is found in virtually all sera (Almost everybody has it!).
classified as an heterophil antibody
Pathogenic Anti-I
cold autoimmune hemolytic anemia or Cold Agglutinin Syndrome
An Anti-I that has a broad thermal range
Anti I & Anti IH
Nuisance antibodies that can be overlooked using prewarm techniques and monospecific AHG
bacteria related to autoanti I
Mycoplasm pneumoniae body develops a strong cold agglutinins as a cross-reactivity response
not well discribed, not normally found in healthy people.
involved in EBV, liver cirrosis, and Myeloid leukemias
Gene responsible for I antigen's branching enzyme
M antigen percentage
N antigen percentage
S antigen percentage
s antigen percentage
The M and N antigens are found on a glycoprotein called
glycophorin A (GPA)
Enzymes enhance
I really love a pink kangaroo (I, Rh, Lewis, ABO, P1, Kidd)
Enzymes destroy
X MD (Xga, MNS, Duffy)
Blood Groups that Exhibit Dosage
"Dr. Martin Luther King"
(Duffy, Rh (except D), MNS, Lutheran, Kidd)
S and s Antigens are located on
glycoprotein B (GPB)
S and s are differentiated by the amino acids at the 29 position:
29th position
S has methionine
s has threonine
Which antibody reacts better at a lower pH of 6.5
Anti-M Antibody
Formaldehyde alters the M and N antigens so that they are recognized as foreign. What antibody is this?
(It has been associated with the rejection of a chilled transplanted kidney.)
The U antigen is a high incidence antigen that is found on RBCs of all individuals except about
1% of Blacks
En(a-) Phenotype
produce anti-Ena, which is an umbrella term for reactivity against various portions of GPA unrelated to M or N, but not all antibodies detect the same portion.
Mk Phenotype
the null phenotype in the MNS system.
Escherichia coli may use
the GPA to gain entry to the urinary tract.
Plasmodium falciparum
use alternative receptors, GPA, GPB, and GPC for cell invasion.
k antigen percentage
K antigen percentage
is very immunogenic, second only to D
K, 10 % of people negative for K create an anti K antibody
The Kpa antigen is found only in
only in whites, 2%
Js^a & Js^b antigen percentages
20% of blacks and <0.1% of whites.
The Ko Phenotype
Lacks all Kell antigens (can produce anti-Ku)
Where is The Kx Antigen found?
Only trace amounts of Kx are found on RBCs of normal Kell phenotypes but elevated levels of Kx are present on Ko cells.
(Not found in Mcleod phenotype)
The McLeod Phenotype & Syndrome
Seen only in males
Transferred through carrier mother
severe mutations and deletions at the XK locus.
RBCs lack Kx and Km antigens and have marked depression of all other Kell antigens
The McLeod Phenotype & Syndrome Hematological picture
Acanthocytic RBCs with decreased deformability and reduced in-vivo survival.
Chronic hemolytic anemia (compensated)
X-linked chronic granulomatous disease.
Chronic Granulomatous Disease (CGD)
Granulocytes exhibit normal phagocytosis of microorganisms but inability to kill ingested pathogens.
The McLeod Phenotype & Syndrome: clinical manifestations
Muscle and nerve disorders
Slow, progressive form of muscular dystrophy
Passively Acquired Antibodies
Antibodies passed to baby by mother through placenta
Unexpected Antibodies
Antibodies discovered through panel testing
Monospecific AHG misses what important antibody?
Gel Technique uses
dextran acrylamide gel (gel contains anti-IgG)
Solid Phase Technique
RBC antigens coat microtiter wells instead of being present on intact RBCs.
(The patient's serum is added to each well along with LISS.)
Mixed field agglutination in antibody panel is due to which antibodies?
associated with anti-Sda and Lutheran antibodies.
Hemolysis in antibody panel is due to which antibodies?
anti-Lea, anti-Leb, anti-PP1Pk, and anti-Vel antibodies.
Factors Affecting the Antibody Screen
temp, cell to serum ratio, length of incubation and pH
Examples of enzymes
Ficin, papain, trypsin, and bromelin
What is adsorption?
The antigen:antibody complex is removed

The serum is then tested in a panel.
Clerical error is
#1 cause of transfusion associated fatalities.
blood to give a weak D
Rh negative
Percentage of people who are Rh negative that when exposed to Rh positive RBCs create an Anti-D
80% of these patients may be expected to make the anti-D antibody.
purpose of FFP
Contains coagulation factors and is used to treat coagulation deficiencies from DIC, liver failure, vitamin K deficiency, Warfarin overdose, or massive transfusion.
what type should be transfused when considering platelets?
Only specific to Rh when involving women in younger years
These antigens are known as "The Travelers"
Fya and Fyb (DUFFY)
Fya antigen percentage
Fyb antigen percentage
Fya and Fyb Antigens are found on what cells/organs
RBCs, brain, colon, spleen, thymus but not found on any other blood cell
Duffy is located on what chromosome?
Chromosome 1
What is the major Duffy antigen in blacks?
what is strange about Fyx?
it types as Fy(b-) but will absorb and elute anti Fyb
(weak expression of Fyb)
Fy3 stands out in the Duffy system because...
It is not destroyed by enzymes
Anti-Fy3 antibody reacts with what antigens
Fya, and Fyb
(at one time it was thought this was a compound antibody)
Receptors that the organism plasmodium use to enter cells
Fya and Fyb
This system is known as the gamblers
Jka antigen percentage
Jkb antigen percentage
Most African Americans are this Kidd phenotype
Most Caucasians are this Kidd phenotype
What antibody system must use fresh serum?
(complement levels are too low in stored serum for these antibodies to react)
The phenotype Jk(a-b-) is found most commonly in what group of peoples?
(Filipinos, Indonesians, Chinese, and Japanese)
The 2 molar urea test is used as a screen for what phenotype?
Lua antigen percentage
Lub antigen percentage
Causes Of The Lu(a-b-) Phenotype
Amorphic gene, Lu
Inhibitor gene, In(Lu), which prevents the normal expression of the Lutheran antigens
Lutheran antibodies have...
...a characteristic loose, mixed-field reactivity in a test tube.
Unique in the blood group systems in that inheritance is on a sex linked basis
Xg antigens
Women: 89%
Men: 66%
where is the Xga chomosome?
short arm of the X chromosome
What antigen is Useful marker in the anthropologic studies of Mongolian ancestry
Diego system Dia
(Also seen in 54% of South American Indians)
Yta antigen percentage
Ytb antigen percentage
Sc1 antigen percentage
Sc2 antigen percentage
Sc3 antigen percentage
Name the five antigens in The Dombrock (ISBT 014) Blood Group System
Gya: Gregory
Jy (Holley)
Joa: Joseph
Name the three antigens in the Colton (ISBT 015) Blood Group System
Coa (99.9% of population)
Cob (10% of population)
Co3: high incidence antigen
Name five of the nine Chido/Rodgers (ISBT 017) Blood Group System
CH1, CH2, CH3, RG1, and RG2 as high incidence antigens.
(Plasma inhibition tests are used to confirm the identity of suspected anti-Ch or anti-Rg antibodies.)
Name three high incidence antigens in the Gerbich (ISBT 020) Blood Group System
Ge2, Ge3, Ge4
name four low incidence antigens in the Gerbich (ISBT 020) Blood Group System
Wb, Lsa, Ana, Dha
Name eight high incidence antigens in the Cromer (ISBT 021) Blood Group System
Cra, Tca, Dra, Esa, IFC, UMC, WESb, GUTI
Name three low incidence antigens in the Cromer (ISBT 021) Blood Group System
Tcb, Tcc, WESa
The Knops (ISBT 022) Blood Group System
Composed of eight antigens:
Kna (Knops)
McCa (McCoy)
S11 (Swain-Langley)
Yka (York)
S12 (vil)
Indian (ISBT 023) Blood GroupSystem is composed of which two antithetical antigens?
Ina (low incidence)
Inb (high incidence)
John Milton Hagen is known as what antigen
JMH (High incidence)
The absence of the JMH antigen:
A. Elderly
B. Paroxysmal nocturnal hemoglobinuria