RH Flashcards
Rh is the most complex system, with over ______ – ________
45 antigens
highly polymorphic genes
consists of six related RBC Ag – ______ – and their corresponding antibodies: ____________ (______ does not exist)
D,C,E,d,c,e
anti-D, anti-C, anti-E, anti-c, and anti-e
anti-d Ab
About _____ variants have been described; _____ are the most important Ag.
50
DCEce
Discovered in ______after work on Rhesus monkeys by _______and ________by in 1939
1940
Landsteiner and Weiner
Levine and Stetson
The 2nd most important after ABO in the crossmatch
RH blood system
RHD and RHCE genes – chromosome ____
1
______ encodes the D antigen, which is a large protein on the RBC membrane, and the most important.
RhD gene
International Society of Blood Transfusion
(004 + 3 digits number)
If one out of the five numbers are not reported, that means the sample ______
was not tested for that designation.
Fisher-Race
(DdCcEe)
Wiener
(Rh-Hr)
Weiner --------- Fisher-Race R0 R1 R2 Rz
Fisher-Race: Dce DCe DcE DCE
Weiner --------- Fisher-Race r r' r'' ry
Fisher-Race: dce dCe dcE dCE
Five major antigens: _______- antigenic; the ____ denotes only the absence of the D antigen
D, C, c, E, e
“d”
___ of the general population is positive to the D antigen; ____ are D-negative
85%
15%
Most common genotype in whites is _____; most common genotype in blacks is ____
R¹r
R⁰r
____ – permanent inherited characteristics that remain constant throughout life
Rh Ag
Antigens are ______ in nature
protein/polypeptide
There are approximately _____ in the Rh blood group system
55 antigens
– strongest and will generally result in immunization if introduced into a foreign host.
D (Rho) Ag
Strength of antibody frequency:
anti-c > anti-E > anti-C > anti-e
Frequency of Common Rh
Antigens in Caucasians
ANTIGEN GENE FREQUENCY (%) D No D C E c e
D - 85 No D - 15 C - 70 E - 30 c - 80 e - 98
Not all RBCs that contain D antigen react equally well with anti-D blood grouping reagent.
Some of these cells may even appear to be D negative, depending on methodology.
This weak reactivity with anti-D sera is referred to as
weak D
____ – Rh antibodies will form only upon exposure to the corresponding antigens; they are not naturally present in the blood
Immunogenic antibodies
Rh Antibodies are _____ and ____ (with ______ being the most clinically significant ones); do not bind complement
warm reactive, IgG
IgG1 and IgG3
Exposure to ______of Rh positive RBCs can stimulate antibody production in an Rh negative person
less than 0.1 mL
Warm autoantibodies often appear to have ______
anti-e-like specificity
Can cross the placenta and cause HDN; Rh mediated hemolytic transfusion reactions usually result in ________
extravascular hemolysis
____ – individuals do not possess the genes needed to synthesize Cc or Ee
D deletion (D–)
______ – individuals lack all Rh antigens on their RBCs;
Rh null phenotype
individuals with Rh null phenotype demonstrates:
mild compensated hemolytic anemia,
reticulocytosis,
slight-to-moderate decrease in Hb and Hct,
increase in hemoglobin F, decrease in serum haptoglobin, increased bilirubin and
stomatocytosi
partially suppressed Rh gene expression; features are similar to Rh null syndrome with milder symptoms
Rh mod
____ antigen is expressed when both c and e in the ___ position or located in the same haplotype (i.e., Dce/DCE)
“f”
cis
“f” antigen is expressed when both c and e in the cis position or located in the same haplotype (i.e., Dce/DCE)
f(ce)
_____ was demonstrated as an antigen present on Rhesus monkey and on majority of human RBCs
LW antigen
_____ was originally thought to be the same as the Rh family, it is now
recognized as distinct from the D antigen and named in honor of Landsteiner and Weiner
LW blood group system