Bloodbanking Final

Kell major antigens

K, k, Kp a/b, Js a/b

Kidd major antigens

Jk a/b

Duffy major antigens

Fy a/b

Kell high frequency antigens

k, Kpb, Jsb

Kidd high frequency antigens

Jka in black people

Frequency of K in caucasian/african american populations

9% vs 2%

Kidd/Kell/Duffy mode of stimulation

transfusion and pregnancy

Kidd/Kell/Duffy optimal phase of reactivity

AHG

Kell effect of enzymes

none

Kidd effect of enzymes

enhanced

Duffy effect of enzymes

destroyed

Kell implication in HDN/HTR

yes

Kidd implication in HDN/HTR

delayed HTR

Duffy implication in HDN/HTR

HTR, uncommon in HDN

Dosage in Kell

no

Dosage in Kidd

yes

Dosage in Duffy

yes

How is the Mcleod phenotype related to the kell system

red cells lack Kx (precursor), no kell ags are expressed, acanthocytes

Duffy genotype that confers resistance to malaria

fy(a-b-), lack glycoprotein receptor needed for malaria to enter RBC, protect against p. vivax

Frequency of the 4 lutheran phenotypes

Lub, Luab, Lua, Lu(a-b-)

Antigen characteristics of Lua/Lub

poorly developed at birth, show dosage, destroyed by enzymes

Characteristics of anti-Lua

mostly IgM, mixed field agglutination, clinically insignificant

Characteristics of anti-Lub

rare, mostly IgG, weak mixed field, causes HTR/HDN

Relationship of Lewis antigens w/ secretors

se status affects type of lewis

Lewis phenotype of nonsecretor

Lea, LeLe, no ABO in saliva

Lewis phenotype of secretor

Leb, Lele, ABO in saliva

Only Lewis phenotype to build antibodies

lele, still a secretor

Major antigens of I system

I, i, Oi

I/i specificity of adult/newborn cells

adult: I, newborn: i

Sources of I and i antigens used in serologic testing

plasma, serum, saliva, milk

Antibodies associated w/ I system

Auto anti-I, Allo anti-I, anti-i

Auto anti-I characteristics

weak IgM, strong RT or AHG, warm supplies before testing

Allo Anti-I characteristics

in adult i individuals

Anti-i characteristics

IgM, associated w/ mono, myeloid leukemia, anemia, cirrhosis

Disease states associated w/ Auto anti-I

cold agglutination syndrome, mycoplasma pneumoniae

5 possible phenotypes in P1 blood group system

P1, P2, p, P1K, P2K

Recount 3 attributes of the P1 antigen

not fully developed at birth, strength varies, neutralized by pigeon eggs

General characteristics of Anti-P1

IgM, seen in P2, neutralized by P1 substance, enhanced by cold/enzymes

General characteristics anti-PP

produced by Pnull/p individuals, reacts w/ all other RBCs, wide temp range

General characteristics of anti-P

found in Pk individuals, potent IgM hemolysin

Clinical significance of Anti-P1

ahg reactive may cause in vivo rbc destruction

Clinical significance of Anti-PP

spontaneous abortion

Clinical significance of Anti-P

paroxysmal cold hemoglobinuria (binds in the cold)

How to detect anti-P

donath-lansteiner test, spectrophotometer

MN antigen glycoprotein

glycophorin A

Ss antigen glycoprotein

glycophorin B

Order of frequency of MNSs gene complexes

Ns, Ms, MS, NS

Frequency of U antigen

high

Associate antigen phenotype S-s-U- w/ black population

1%

Anti-M lectin

iberis amara

Anti-N lectin

vicia graminea

General characteristics of Anti-M

mostly IgM, no complement, destroyed by enzymes, dosage, pH dependent

Which antibody likes acidity

anti-M

General characteristics of Anti-N

cold reactive, no complement, insignificant, dosage

Where is anti-Nf seen

dialysis patients

General characteristics of Anti-S/s

IgG, cause HDN/HTR, maybe enzymes/dosage

Xga characteristics

sex-linked, X

Dia characteristics

south american indians

Vel characteristics

rare HTR (IgM)

Sda charateristics

mixed field, shiny refractile agglutination, neutralized w/ pos urine

Principle of antiglobulin reaction

based on a reagent prepared by injecting rabbits w/ human ab and complement proteins, animal produces abs which are manufactured and agglutinate w/ IgG-coated red cells

Source of AHG

rabbits

Types of AHG

poly and monospecific

Polyspecific AHG

screening for anti-IgG and Anti-C3d

Applications of Poly AHG

complete crossmatching, alloantibody screening/ID, DAT

Monospecific AHG

specify anti-IgG or anti-C3d

Anti-IgG AHG

reacts w/ heavy chain (Fc) of IgG

Anti-C3d AHG

component of complement associated w/ immune hemolysis

Applications of anti-IgG AHG

detects almost all clinically significant coating antibodies

Applications of anti-C3d AHG

AIHA, DAT fractionation

Importance of Coombs control

ensure testing was completed/valid

What is in coomb’s check cells

Group O pos RBC’s coated w/ IgG anti-D

Causes of false pos in AHG testing

bacterial contamination, overcentrifugation, dirty glassware

Causes of false neg in AHG testing

inadequate washing, AHG reagent not added, expired AHG, undercentrifugation

Purpose of DAT

detects in vivo IgG or complement sensitized red cells

Procedure for DAT

cell suspension, wash, AHG, SRR, microscope if neg

Applications for DAT

HDN, HTR, AIHA, Drug-induced abs

Purpose of IAT

detects in vitro Ag/Ab reactions

Procedure for IAT

incubate, wash, AHG, SRR, microscope neg except for weak D

Applications of IAT

ab screening/ID, crossmatching, phenotyping, weak D

Why is an EDTA tube required for DAT

anticoagulant removes Ca needed for agglutination to occur

False positive DAT cause

specimen taken from IV line, pt w/ septicemia

Characteristics of clinically significant alloantibody

decrease survival of RBCs, HTR/HDN

Always clinically significant antibodies

ABO, Rh, Kell, Kidd, Duffy, S/s, U

Occasionally clinically significant antibodies

Leb, MN, P1, L

Rarely clinically significant antibody

Lea

High frequency antigens

k, Jsb, Kpb, U, e

Low frequency antigens

Jsa, Kpa, K, Lua

IgG blood groups

Rh, S, Kell, Kidd, Duffy, LuB, sometimes Lewis

IgM blood groups

MN, Lewis, Lua, P1, I

Antigens exhibiting dosage

MNSs, Duffy, Kidd, Rh

Antigens developed at birth

ABO, MN, Lutheran, P, Lewis

Complement binding blood groups

ABO, duffy?, kidd, lewis

Warm blood groups

Rh, Kell, Duffy, Kidd

Cold blood groups

MN, P1

Cells destroyed by enzymes

MN, Duffy

Cells enhanced by enzymes

Rh, Kidd

Clinical Significance of Rh System

D antigen is second in immunogenicity, Abs are immune stimulated

How are Rh genes inherited

codominantly

Phenotype of Rh

D pos or neg