Other Blood Groups Flashcards
I/i Antigens
Subterminal portions of oligosaccharides that form A, B, and H antigens
i
Minimally-branched oligosaccharide
Abundant on fetal cells
Cord blood
I
Highly-branched oligosaccharide
Built from “i” antigen
Abundant on Adult Cells
I/i Found
on WBCs
Platelets
Secretions
Anti-I
Autoantibody
IgM antibody
Narrow thermal range & low titer
“Naturally Occurring”
Mycoplasma pneumoniae gives cross reaction
Anti-I Conditions
Cold Agglutinin Syndrome (Raynaud Syndrome)
Wider thermal range & higher titer
Binds complement
Anti-i
Very rare
Autoantibody IgM
Strongest reacting with cord cells
Infectious mononuceleosis
Anti-IH
Antibody common in A1 and A1B blood types
Anti IH reacts strongest with O and A2
Does not agglutinate Group O cord cells
Requires patient to form both Anti-I and Anti-H
Anti-IA
Antibody may be found in Group B blood types
Requires both Anti-I and Anti-A to bind
Anti-H
Common in A1 and A1B
Reacts strongly with Group O and Group A2B
Anti-H vs Bombay Anti-H
Bombay: Strong ALLOantibody (IgG) upon exposure
Anti-H: “Cold” Autoantibody (IgM) no exposure required
Cold Auto Antibodies (Transfusion)
Do not usually cause RBC Destruction
May mask significant antibodies
Cold Auto Antibodies ABO/Rh Typing
Discrepancies in Reverse Group
Interfere with Rh control (+ DAT)
Cold Auto Antibodies Testing
Can result in all positive reactions
Masking can occur at RT and AHG (very strong antibodies)
Cold Auto Antibodies Compatibility Testing
Antibodies may react with donor cells
Cold Auto Antibodies Reaction
Screening Cells I (SCI) IS pos, 37 C neg
Screening Cells II (SCII) IS pos, 37 C neg
Screening Cells III (SCIII) IS pos, 37 C neg
Auto Control (Self) IS pos, 37 C neg
Cold Allo Antibodies Reaction
Screening Cells I (SCI) IS pos, 37 C neg
Screening Cells II (SCII) IS neg, 37 C neg
Screening Cells III (SCIII) IS neg, 37 C neg
Auto Control (Self) IS neg, 37 C neg
Cold Screen
Screening Cells
Auto Control (Patient Cells + Patient Serum)
Type “O” Cord Cells - I vs i
A1c - small amount of H
A2c - more amount of H compared to A1c
Bc - more amount of H compared to A2c
Pre-Warming technique
IAT at 37 C and AHG only testing
Used to remove cold autoantibody interference
Allows tech to check for significant antibodies
Identify Warm Antibody (IgG)
May need to prewarm blood for transfusion
P Blood Group
Discovered by Landseinter & Levine
Antigen production similar to ABO
P Group Antigens
Present on all human RBCs
P1 Antigen
Most common
Varies in strength
Poorly developed at birth
Deteriorates with storage
pK Antigen
Converted to P antigen
P1 Phenotype
Has P and P1 antigen
79% Caucasians
94% African Americans
P2 Phenotype
Has P antigen
Lacks P1
Can Make Anti-P1
p Phenotype
Rare
No detectable Antigens
Can Make Anti PP1 pk
Originally called Anti-Tja
p1k Phenotype
Very Rare
Has P1 & pk antigens
Lacks P antigen (Can make Anti P)
p2k Phenotype
Very Rare
Has pk Antigen
Lacks P & P1 Antigens (Can make Anti P & Anti P1)
Anti-P1
Most Common
Naturally Occurring (IgM)
Weak - usually not hemolytic, no HDN
Optimal Activity at 4 C
P1 substance - neutralizes Anti P1 Activity
Anti-P
Strong Antibody
pk phenotypes can produce
Naturally occurring (IgM)
Rarely seen
PCH
IgG
Biphasic hemolysin - binds complement
Donath-Landsteiner Test
Anti-PP1pk
p phenotype can produce
Naturally occurring (most IgM, some IgG)
Binds complement
Strong hemolysin
HTR & HDN
Lewis Blood Group
Lea and Leb
Poorly developed at birth
Does NOT show dosage
Le gene
Codes Lewis Blood Group
Produced by glycosyl transferases
Le/Le or Le/le
Fucosyl transferase that adds fucose to subterminal sugar
Type I chains in plasma
Produces Lea activity
Type II chains on RBCs
no Le activity
Type I chains
Reversibly adsorbed onto RBC membrane
Se/Se or Se/se AND Le/Le or Le/le
Se gene codes for fucosyl transferase - Leb
Attaches fucose to terminal galactose
H gene must have added fucose to IH chain
Leb adsorbed preferentially over Lea
Lea-b+
Most common phenotype
Lea+b+
Rare
Asian population
le/le
No Lewis antigens produced
Rare
Lea-b-
Lewis antigens
Poorly developed at birth
Detectable in plasma at 10 days after birth
Accurate type at ~ 6 yrs
Lewis Antibodies
Occur in Lea-b- persons
IgM and binds complement
Not usually clinically significant
Enhanced by enzyme treatment
Lacy agglutination - easily dispersed
MNSsU Blood Group
MNSs are genetically linked
Most popular are: M+, N+, s+
Anti S most common antibody
M & N Antigens
Co-dominant alleles
Shows dosage
Well developed at birth
Primarily RBC antigen
Built on glycophorin A
Destroyed by enzymes
Anti M
Naturally occurring
IgM
Do not bind complement
Shows dosage
Rare cause of HTR or HDNA
Anti N
Same as Anti M (less common)
Lectin - extracted from Vicia graminea
Found in dialysis patients when equipment sterilized with formaldehyde
S and s antigen
Codominant alleles
Shows dosage
Well developed at birth
RBC antigen
Built on glycophorin B
Destroyed by enzymes
U antigen
High incidence antigen
>99% of population is U+
<1% of African Americans are U-
Anti S, Anti s, and Anti U
Warm reacting
37 C and AHG
IgG (Immune production)
May bind complement
Associated with HTR and HDN
Must provide antigen negative blood
Lutheran Blood Group
Lua and Lub
Ag have high or low frequencies
Co-dominant alleles
Poorly developed at birth
Show dosage
Lu gene
Chromosome 19
Linked to Se gene
Lutheran phenotypes
Lua+b- <1%
Lua+b+ 5-7%
Lua-b+ >90%
Lua-b- very rare
Anti Lua
Naturally occurring saline agglutinin
Reacts best at RT
IgM, IgG, IgA
Agglutination is mf, lacy
May cause mild HDN
Anti Lub
Most are immune mediated, some naturally occurring
IgG - Reacts at 37 C and AHG
Associated with mild HDN
KELL Blood Group
K, k, Kpa, Kpb, Jsa, Jsb
Glycoproteins
Well developed at birth
Show dosage
Antigens denatured by DDT, ZZAP, 2ME
KELL Antigens
K (KEL1) Present in 9% Caucasians, 2% African Americans
k (KEL2 - cellano) Present in 98-100% of population
KELL Antibodies
Warm reacting - 37 C & AHG
IgG
Immune mediated
Can show dosage
Anti K
Frequently seen
Clinically significant - HTR & HDN
Must give Ag negative blood
Some IgM Anti K due to bacterial identification
Anti k
Rarely seen
Clinically significant - HTR & HDN
Must give Ag negative blood
Kpa & Jsa
Low frequency antigens
Antibodies behave like anti K
Easy to find Ag negative blood
Kpb & Jsb
High frequency antigens
Antibodies behave like anti K
Hard to find Ag negative blood
Kx
Previously thought to be K precursor
Now in own system (XK)
Ko
Silent allele
Ko/Ko = K null phenotype
Have only Kx on RBCs
McLeod Phenotype
Appears like K null
- weak expression of k, Kpb, and Jsb
Acanthocytes
Patients have abnormal neuromuscular activity
Associated with CGD
Duffy Blood Group
Gene located on chromosome 1
Antigens well developed at birth
Antigens moderately immunogenic
Antigens destroyed by enzymes & ZZAP
Duffy Antigens
Fya and Fyb
Codominate alleles
Fy
3rd allele
High incidence in African Americans
Fyx
Weakened Fyb antigen
Duffy Antibodies
Warm reacting - 37 C, AHG
Rarely bind complemet
Enhanced by LISS
May show dosage
HTR, HDN
Ag negative blood required
Fya-b-
Resistant to P. vivax
Helps to avoid malaria
Fy glycoprotein
Recept for P. vivax
KIDD Blood Group
2 antigens
Jka and Jkb
Co-dominate alleles
Well developed at birth
Show dosage
Weakly immunogenic
KIDD Antibodies
Immune Production
Warm Reacting - 37 C and AHG
IgG
Bind Complement Well
HDN (mild) and HTR (can be severe)