(P) Rh BGS Flashcards
- most important blood group system after ABO
in transfusion medicine.
*Critical component of pre-transfusion and prenatal testing
Rh BGS
Who described a hemolytic transfusion reaction in 1939 in an OB patient that led to the discovery that the fetus and the father possessed a common factor that the mother lacked
Levine and Stetson
described an
antibody made by guinea pigs and rabbits when they
were transfused with rhesus macaque monkey RBCs
Consequently, these guinea pigs and rabbits developed
antibodies which react or agglutinated 85% of human
RBCs and was named anti-Rh
They postulated that the antibody that was identified to
the previously mentioned OB patient was the same
antibody produced by the guinea pigs against the rhesus
macaque monkey RBCs.
Landsteiner and Wiener
what was the name of the antibody that Landsteiner and Wiener discovered?
anti-Rh
- What was the name for the human produced antibody
- What was the new name for the animals’ antibody
- Rh
- anti-LW
- after A and B, is the most important RBC
antigen in transfusion practice
*an immune antibody, which is produced
in response to the exposure to the foreign antigen, occurs through blood transfusion or
pregnancy
- antigen with the greatest immunogenecity
D antigen
detection of Rh status is performed (together / separately) from ABO typing
together
(ABO-Rh typing)
how many percent of D negative individuals who receive a single unit of D positive blood can be expected to develop immune anti-D
> 80%
__________ is clinically significant as it can produce
hemolytic transfusion reaction (HTR) and hemolytic
disease of the newborn (HDN )
anti-D
what type of red cells must be transfused for individuals that has present D negative red cells?
D negative red cells also
What happens when a Rh-negative person is exposed to less than 0.1 ml of Rh positive RBC
antibody production
RH BGS BASICS
- Indicates that the red blood
cells lack the D antigen. - ndicates that an individual’s
red blood cells possess one
particular Rh antigen, the D
antigen.
- Rh negative
- Rh positive
the following can be found on which chromosome?
- ABO BGS
- Rh BGS
- RHAG
- chromosome 9
- chromosome 1
- chromosome 6
INHERITANCE: MOLECULAR GENETICS OF RH
a. RHD
b. RHCE
c. both
d. neither
- Codes for the presence or absence of the RhD protein
- Gene product: RhCe, RhcE, Rhce, or RhCE
- Gene product: RhD protein
- It is inherited in a codominant manner
- Non-glycosylated
- a
- b
- a
- c
- c
Where do Rh antigens reside?
Transmembrane proteins
INHERITANCE: MOLECULAR GENETICS OF RH
a. RHD
b. RHCE
c. both
d. neither
- Glycosylated
- composed of 416 amino acids
- traverses the cell membrane 16 times
- d (non-glycosylated)
- c
- d (12 times)
Amino acid position
a. 103 AA
b. 112 AA
c. 226 AA
- determines C or c expression
- differentiates E from e
- a
- c
the following are true of Rh function except:
a. found exclusively on red blood cells
b. maintains structural integrity of RBCs
c. CO2 transporters
d. lactic acid transporters
d
familiarize the 4 nomenclatures
- Fisher-Race: DCE terminology
- Wiener: Rh-hr terminology
- Rosenfield & Coworkers: alpha/numeric terminology
- International Society of Blood Transfusion (ISBT):
numeric terminology
- Fisher-Race: DCE terminology
- Wiener: Rh-hr terminology
- Rosenfield & Coworkers: alpha/numeric terminology
- International Society of Blood Transfusion (ISBT):
numeric terminology
NOMENCLATURE OF THE RH SYSTEM
- based on the theory that the antigen of the system were produced by three closely linked set of alleles, each gene was responsible for producing a product
- based on genetic mechaism
- three loci carry the RH genes whichare closely linked that they never seperate but are passed down from generation to generation as a unit or gene complex
Fisher-Race : DCE terminology
this represents the absence of D in the Fisher-race nomenclature
d
what are the five common antigens in the Fisher-Race nomenclature
D,C,c,E,e
NOMENCLATURE OF THE RH SYSTEM
- Rh gene: 2 genes, one on each chromosome pair
- Rh gene produces a structure on the RBC called an
agglutinogen, instead of a set of gene complex - ___________believed there was one gene responsible for defining
Rh that produced an agglutinogen comprising of three Rh
factors/ blood factors
WIENER: Rh-Hr TERMINOLOGY
What theory is this:
antibody will recognize each factor within the agglutinogen
Wiener’s agglutinogen theory
familiarize the 8 agglutinogens of the Wiener agglutinogen theory
R0, R1, R2, RZ, r, r’, r’’, and rY
WIENER NOMENCLATURE RULES
- The uppercase R denotes the (presence/absence) of the D antigen.
- The lowercase r indicates the (presence/absence) of D antigen.
- presence
- absence
- a nomenclature based only on serologic
(agglutination) reactions. - Wherever it’s tested positive, you will write the numeric
number of that antigen. - Each antigen is assigned with a numeric number
- has no genetic assumptions or basis
ROSENFIELD AND COWORKERS: ALPHANUMERIC
TERMINOLOGY
what signifies the absence of the antigen in the ROSENFIELD AND COWORKERS: ALPHANUMERIC
TERMINOLOGY
minus sign (-)
- International organization created to standardize blood
group system nomenclature. - Numeric terminology
- The ISBT adopted a six-digit number for each
authenticated antigen belonging to a blood group system.
INTERNATIONAL SOCIETY OF BLOOD
TRANSFUSION COMMITTEE
ISBT terminology
what number was assigned to the Rh BGS
004
Provide the numeric equivalent of the following antigens:
- D
- C
- E
- c
- e
- 004001
- 004002
- 004003
- 004004
- 004005
list down all of the Rh antigens from most immunogenic to the least immunogenic
D > c > E > C > e
Rosenfield code: 1 4 3 2 5 (D=1, c= 4, E= 3, C=2, e= 5)