4-CHAPTER-II-LESSON-2 Flashcards
Represents phenotypes that show weaker variable serologic reactivity with the commonly used human polyclonal anti-A, anti-B, and anti-AB reagents.
ABO SUBGROUPS
The weaker (?) is attributed to the decreased number of A and B antigen sites on their red cells.
serologic reactivity of ABO subgroups
In 1911, von Dungern descried (?) based on reactions between group A RBCs and anti-A and anti-A1.
two different A antigens
Cause discrepancies in ABO testing and cross matches.
A SUBGROUPS
Group A RBCs that react with both anti-A and anti-A1 are classified as ?
A1
Those that react with anti-A and not anti-A1 are classified as ?.
A2
Classification into A1 and A2 cells account for (?) of all group A individuals.
99%
BLOOD GROUP A1 ANTI-A REAGENT
+
BLOOD GROUP A1 ANTI-A1 LECTIN REAGENT
0
BLOOD GROUP A2 ANTI-A REAGENT
+
BLOOD GROUP ANTI-A1 LECTIN REAGENT
+
Number of antigen sites
QUANTITATIVE
Amount of transferase enzyme
QUANTITATIVE
Amount of branching
QUANTITATIVE
Differences in the precursor oligosaccharide chains
QUALITATIVE
Subtle differences in transferase enzymes
QUALITATIVE
Formation of anti-A1, in a percentage of some subgroups
QUALITATIVE
The immunodominant sugar on both A1 and A2 RBCs is ?
N-actyl- D-galactosamine
Differentiation of (?) can be determined by using a reagent made from the seeds of the plant Dolichos biflorus
A1 and A2 phenotypes
is found in greatest concentration on the RBCs of O individuals
H antigen
Reactivity of anti-H antisera or anti-H lectin with ABO blood groups:
O > A2 > B > A2B > A1 > A1B
- agglutinates A1 or A1B
Dolichos biflorus
B cells
Bandeiraea simplicifoliaagglutinates
- agglutinates O cells (H specificity) and other ABO blood groups depending on the amount of H antigen available
Ulex europaeus
In accordance with Landsteiner’s rule for expected ABO antibodies, sera from group O and B individuals contain ?.
anti-A antibodies
The anti-A produced by group O and B individuals can be separated by adsorption and elution techniques into two components:
anti-A and anti-A1
is specific for the A1 antigen and does not agglutinate A2 red cells.
Anti-A1
The optimal reactivity of this antibody is at ?.
room temperature or lower
is not considered clinically significant for transfusion purposes.
Anti- A1
Anti-A1 becomes a concern when it causes problems with (?) on immediate spin.
ABO phenotyping results and incompatible crossmatches
? does not exist because the A2 phenotype possesses the same A antigens as A1 phenotype but in reduced quantities.
Anti-A2
Individuals with A1 phenotype do not respond immunologically when exposed to ? .
A2 red cells
