RH Blood Group System Flashcards
ROUTINE RH TYPING
Detects:_______
Specimen:____________
Rgt:________
Result:_____
Detects: D antigen
Specimen: Whole Blood
Rgt: AHG Anti-B (antisera)
Result: Agglutination - Rh negative
No agglu - Rh positive
WEAK D TYPING (Du)
A form of: _________
Specimen: __________
Rgt: _________
Result: _________
A form of: IAT
Specimen: whole blood / RCS( neg control: bovine albumin)
Rgt: AHG
Result: Agglu- weak D pos reported as Rh pos
No Agglu- Rh neg
Blood recipients with the C trans weak D, genetic weak D have complete Ag and cannot reproduce allo-anti D. What can be transfused?
Rh positive blood
All Rh negative, weak D negative obstetric patients are candidates for _____
Rh immune globulin
It si a purified Anti D prepared from immunized donors and GIVEN TO D- NEGATIVE MOTHERS to prevent formation of anti-D
RhIg ( RhoGAM)
Lacks ALL Rh antigen on their RBCs
Rhnull syndrome
A mutation on RHAG gene and can pass through normal genes of children
Regulator type Rhnull syndrome
Mutation in each RHCE gene and the common deletion of RHD gene
Amorphic type Rhnull syndrome
Partial suppression of RH gene expression caused by mutations of RHAG gene
Rhmod phenotype
Differentiation of ABO and RH
Reaction phase of RH
37C at IAT PHASE
Antigen composition of Rh blood group
Nonglycosylated proteins
Antibody produce by injecting rehuses monkey rbc’s I to guinea pigs and rabbits, having the same specificity as the antibody Levine and Stetson decribed
Anti-LW
Reacts:
strongly - D- positive RBCs
Weakly - Rh neg RBCs
Never - Rhnull cells
Anti-LW
Most immunogenic Rh antigen.
D
Most immunogenic :D>c>E>C>e: least
Present of 85% of whites, and a higher percentage of blacks, American, indians and Asians.
D antigens
A nomenclature that based on postulated genetic mechanism of Rh antigen
Fisher race / DCE and Wiener /Rh-Hr
A nomenclature that describes the presence or absence of antigen
Rosenfield/ Alphanumeric terminology
Antigens were produced by THREE CLOSELY LINKED SETS OF ALLELES
Fisher Race/ DCE terminology
Codes for the presence or absence of D antigen. Located at chromosome 1.
RHD
Codes for the expression of Cc andEe antigens. Located at chromosome 1.
RHCE
Produced Rh associated glycoprotein.
Considered as CO-EXORESSOR.
RHAG
Denotes absence of D
d
Postulated that Rh gene produced AGGLUTINOGEN which contains AT LEAST 3 BLOOD FACTORS, each factor an antigen.
Wiener:Rh-Hr terminology
A substance that stimulates production of agglutinin thereby acting as an antigen.
AGGLUTINOGEN
Complement of genes inherited form either parents
HAPLOTYPE
Gene association:
Dce -
DCe -
DcE -
DCE -
dce -
dCe -
dcE -
dCE -
Dce - Rh0
DCe - Rh1
DcE - Rh2
DCE - Rhz
dce - rh
dCe - rh’
dcE - rh’’
dCE - rhy
System that assigns number to each antigen. No genetic basis.
Rosenfield/Alphanumeric terminology
Adopted a six digit number for each authenticated antigen binding to a blood group system
International society of blood transfusion committee: Updated numeric terminology
Haplotype frequency in black, white, and Asians.
Black: Ro>r>R1>R2
White: R1>r>R2>RD
Asians: R1>r>R2>Ro
Importance of Rh terminologies
- parentage studies
- predicting potential of HDN
Main function of Rh antigen.
-Transport of ammonia and carbon dioxide
-maintain the structural integrity of RBC membrane
The greatest number of D antigen sites are on cells of the rare Rh phenotype of ________
D –
Carry only D antigen and completely lack C c and E e
D –
Cells posses the LARGEST NUMBER OF D antigen sites
R2R2
Most common D positive genotype
R1r
Most common D negative genotype
rr
Inheritance of RHD genes that code for a WEAKENED EXPRESSION OF D ANTIGEN.
Seen frequently in BLACK PERSONS
Genetic Weak D
Position effect or gene interaction effect.
They can receive D positive RBC’S with no adverse effects.
C in trans to RHD
D antigen expression can be weakened when ONE OR MORE D EPITOPES WITHIN THE ENTIRE PROTEIN IS MISSING OR ALTERED
Partial D
Extremely low number of D antigen sites .
Adsorbing and eluting anti- D from individuals red cells.
Relatively common on Asians
Del
Type positive with anti-D even though the D epitope is on the RHCE protein.
D EPITOPES on RhCE protein
Results from a hybrid gene RHCE-RHD-RHCE where only a small portion of RHD is on RHCE protein
DHAR
African descent; amino acid change in the RHce gene
ceCF ( Crawford)
Identify the detection method of the following:
Genetic weak D: _________
C in trans to RHD: _______
Partial D: _______
Genetic weak D: Weak D test
C in trans to RHD: Monoclonal reagents
Partial D: Weak D or Monoclonal
