BB LEC - ABO Blood System Part 2 Flashcards
reagent not used in routine ABO testing of donors and recipients but is used to resolve ABO typing problems
Anti-A1
Resolves ABO typing problems when A2 phenotypes develop anti-A1
Anti-A1 lectin
grade reaction of A1 and A2 phenotypes with commercial Anti-A reagents
3+ to 4+
B subgroups with only H substances in saliva
Bx and Bel
B subgroups with no B transferase in serum
Bx and Bel
unexpected antibody of this B subgroup is Anti-B
Bx
A and B specificity demonstrated only by ___
elution/adsorption studies
immunohematologic technique that uses red cells (known antigens) to remove red cell antibodies from a solution (plasma or antisera); group A red cells can remove anti-A from solution.
Adsorption:
process that dissociates antigen-antibody complexes on red cells; freed IgG antibody is tested for specificity.
Elution:
recessive allele of the ABO blood group system
O allele
Non–red blood cell stimulated: immunologic stimulus for antibody production is unrelated to a red cell antigen
Non–red blood cell stimulated:
Ig forms of Anti-A and Anti-B capable of activation and binding of complement and eventual hemolysis of red cells
IgG and IgM
genetic disease characterized by reduced levels of gamma globulin in the blood.
Congenital hypogammaglobulinemia:
lower than normal levels of gamma globulin in the blood associated with malignant diseases (chronic leukemias and myeloma) and immunosuppressive therapy.
Acquired hypogammaglobulinemia:
genetic disease characterized by the absence of gamma globulin and antibodies in the blood.
Congenital agammaglobulinemia:
absence of gamma globulin and antibodies associated with malignant diseases such as leukemia, myeloma, or lymphoma.
Acquired agammaglobulinemia:
WHICH AB react in immediate-spin phases
Anti-A and Anti-B
Activity of human anti-??? is regarded as a specificity that is cross-reactive with both A and B antigens.
Anti-A,B
A ____ is capable of recognizing a particular molecular structure (antigenic determi- nant) common to several molecules.
cross-reactive antibody
Human ___ also manifests the property of agglutinating red cells of infrequent subgroups of A, particularly Ax.
anti-A,B
___ does not exist because the A2 phenotype possesses the same A antigens as A1 phenotype but in reduced quantities.
Anti-A2
is not required for confirmatory testing of labeled, previously typed donor RBCs and in infants younger than 4 months
of age.
Reverse grouping (serum or plasma testing)
T or F
Neither human anti-A,B nor the monoclonal blend anti-A,B is required in ABO typing
TRUE
ABO discrepancies that affect the testing of red cells (forward grouping) can be classified into three categories:
extra antigens present, missing or weak antigens, and mixed-field reactions.
Observations that denote discrepancies
weaker agglutination strengths
missing expected reactions
extra reactions
group A1 individual with disease of the lower gastrointestinal tract, cancer of the colon and rectum, intestinal obstruction, or gram-negative septicemia who acquires reactivity with anti-B reagents in ABO
red cell testing and appears as group AB.
Group A with acquired B antigen:
group B individual who acquires reactivity with anti-A reagents in ABO red cell testing; in these individuals, the B gene transfers trace amounts of the immunodominant sugar for the A antigen and the immunodominant sugar for the B antigen.
B(A) phenotype:
property of cells that causes them to be agglutinated by naturally occurring antibodies found in most human sera; agglutination occurs regardless of blood type.
Polyagglutination:
gelatinous tissue contaminant in cord blood samples that may interfere in immunohematologic tests.
Wharton’s jelly:
type of polyagglutination that occurs from a mutation in
the hematopoietic tissue, characterized by mixed-field reactions in agglutination testing.
Tn-polyagglutinable red cells:
__ cells, which are group O reagent red cells, are used to detect an alloantibody because they lack A and B antigens.
Screening
Rouleaux can produce FALSE-__ agglutination in testing.
false-positive
malignant neoplasm of the bone marrow characterized by abnormal proteins in the plasma and urine.
Multiple myeloma:
overproduction of IgM by the clones of a plasma B cell in response to an antigenic signal; increased viscosity of blood is observed.
Waldenström’s macroglobulinemia:
test to distinguish rouleaux and true agglutination.
Saline replacement technique:
Those with Bombay phenotype has results in backward and forward typing similar to what blood type
O
Antibodies of Bombay individuals
anti-A, anti-B, and anti-A,B, anti-H
is of clinical significance because this antibody is capable of high thermal activity at 37° C and complement activation with resulting hemolysis.
anti-H in the Bombay phenotype
preferentially adds fucose to type 2 chains.
H gene, FUT1,
H gene product
FUT1
gene product of the Se allele, ___, is an L-fucosyltransferase that preferentially adds L-fucose to type 1 oligosaccharide chain structures in secretory glands.
FUT2
