[4] CHAPTER II LESSON 2 Flashcards

1
Q

2Represents phenotypes that show weaker variable serologic reactivity with the commonly used human polyclonal anti-A, anti-B, and anti-AB reagents.

A

ABO SUBGROUPS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

The weaker serologic reactivity of ABO subgroups is attributed to the decreased number of [?] on their red cells.

A

A and B antigen sites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

In 1911, [?] descried two different A antigens based on reactions between group A RBCs and anti-A and anti-A1.

A

von Dungern

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Cause discrepancies in [?].

A

ABO testing and cross matches

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Group A RBCs that react with both [?] are classified as A1

A

anti-A and anti-A1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Those that react with [?] and not anti-A1 are classified as A2.

A

anti-A

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Classification into A1 and A2 cells account for [?] of all group A individuals

A

99%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

BLOOD GROUP A1 ANTI-A REAGENT

A

+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

BLOOD GROUP A1 ANTI-A1 LECTIN REAGENT

A

0

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

BLOOD GROUP A2 ANTI-A REAGENT

A

+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

BLOOD GROUP A2 ANTI-A1 LECTIN REAGENT

A

+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Differences in the precursor oligosaccharide chains

A

↓ Number of antigen sites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Subtle differences in transferase enzymes

A

↓ Amount of transferase enzyme

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Formation of anti-A1, in a percentage of some subgroups

A

↓ Amount of branching

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

The immunodominant sugar on both A1 and A2 RBCs is

A

N-actylD-galactosamine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Differentiation of A1 and A2 phenotypes can be determined by using a reagent made from the seeds of the plant

A

Dolichos biflorus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

is found in greatest concentration on the RBCs of O individuals

A

H antigen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Reactivity of anti-H antisera or anti-H lectin with ABO blood groups:

A

O > A2 > B > A2B > A1 > A1B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q
  • agglutinates A1 or A1B
A
  1. Dolichos biflorus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

agglutinates B cells

A
  1. Bandeiraea simplicifolia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q
  • agglutinates O cells (H specificity) and other ABO blood groups depending on the amount of H antigen available
A
  1. Ulex europaeus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

In accordance with Landsteiner’s rule for expected ABO antibodies, sera from group O and B individuals contain

A

anti-A antibodies.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

The anti-A produced by group O and B individuals can be separated by adsorption and elution techniques into two components:

A

anti-A and anti-A1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

is specific for the A1 antigen and does not agglutinate A2 red cells

A

Anti-A1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

The optimal reactivity of this antibody is at room temperature or lower.

A

AntiA1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

is not considered clinically significant for transfusion purposes

A

AntiA1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

becomes a concern when it causes problems with ABO phenotyping results and incompatible crossmatches on immediate spin

A

AntiA1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

does not exist because the A2 phenotype possesses the same A antigens as A1 phenotype but in reduced quantities.

A

Anti-A2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Individuals with A1 phenotype do not respond immunologically when exposed to

A

A2 red cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

A1 Anti A

A

4+

31
Q

A1 Anti A

A

0

32
Q

A1 Anti B

A

4+

33
Q

A1 AntiA,B

A

4+

34
Q

A1 Anti A1

A

4+

35
Q

A1 Common

A

anti-B

36
Q

A1 Unexpected

A

None

37
Q

A1 Subs. Present in the saliva of secretors

A

A, H

38
Q

A1 Number of antigen sites RBC x 103

A

810-1170

39
Q

A2 Anti A

A

4+

40
Q

A2 Anti B

A

0

41
Q

A2 AntiA,B

A

4+

42
Q

A2 Anti A1

A

0

43
Q

A2 Common

A

anti-B

44
Q

A2 Unexpected

A

anti- A1 (1%-8% of cases)

45
Q

A2 Subs. Present in the saliva of secretors

A

A, H

46
Q

A2 Subs. Present in the saliva of secretors

A

A, H

47
Q

A2 Number of antigen sites RBC x 103

A

240-290

48
Q

Subgroups weaker than [?] occur infrequently and are most often recognized through an ABO discrepancy (unexpected reactions in the forward and reverse grouping).

A

A2

49
Q

These subgroups of A make up [?] of those encountered in the laboratory and therefore are mainly of academic interest.

A

1%

50
Q

can be utilized to subdivide A individuals into A3, Ax, Aend, etc.

A

Secretor studies, adsorption-elution tests, and molecular testing

51
Q

Occasionally, weak subgroups of [?] may present practical problems, for example, if an Ax donor was mistyped as group O and was transfused to a group O patient.

A

A

52
Q

This is potentially dangerous because the group O patient possesses [?], which agglutinates and lyses Ax RBCs, causing rapid intravascular hemolysis.

A

anti-A,B

53
Q

Characteristics:
1. Decreased number of [?] (resulting in weak or no agglutination with human polyclonal anti-A)
2. Varying degrees of agglutination by [?]
3. Increased variability in the detectability of [?] resulting in strong reactions with anti-H
4. Presence or absence of [?] in the serum

A

A antigen sites per RBC

human anti-A,B

H antigen

anti-A1

54
Q

Weak A phenotypes can be serologically differentiated using the following techniques:
1. Forward grouping of [?] with anti-A, anti-A,B and anti-H
2. Reverse grouping of [?] and the presence of [?]
3. Adsorption-elution tests with [?]
4. Saliva studies to detect the presence of [?]

A

A and H antigens

ABO isoagglutinins; antiA1

anti-A

A and H substances

55
Q

Additional special procedures such as [?] for detecting the A enzyme that can be performed for the differentiation of weak subgroups.

A

molecular testing, serum glycosyltransferase studies

56
Q

Absence of a disease process should be confirmed before subgroup investigation because [?] are altered in various malignancies and other hematologic disorders.

A

ABH antigens

57
Q

Weak A subgroups can be distinguished as:

A
58
Q

Characteristically demonstrate a mixed field pattern of agglutination with anti-A and anti-A,B reagents.

A

A3 RBCs

59
Q

The estimated number of A antigen sites is approximately 35,000 per RBC.

A

A3 RBCs

60
Q

Weak a-3-N-acetylgalactosamine activity is detectable in the serum.

A

A3 RBCs

61
Q

Anti-A1 may be present in serum of A3 individuals, and A substance is detected in the saliva of A3 secretors.

A

A3 RBCs

62
Q

Characteristically not agglutinated by anti-A reagent but do agglutinate with most examples of anti-A,B

A

Ax RBCs

63
Q

Characteristically not agglutinated by anti-A reagent but do agglutinate with most examples of anti-A,B

A

Ax RBCs

64
Q

Estimated number of A antigen sites is approximately 4,000 per RBC

A

Ax RBCs

65
Q

Anti-A can be adsorbed and then eluted from Ax cells without difficulty.

A

Ax RBCs

66
Q

Transferase: not detectable in the serum or in the RBC membranes of Ax individuals

A

Ax RBCs

67
Q

individuals almost always produce anti-A1 in their serum

A

Ax RBCs

68
Q

Routine secretor studies detect the presence of only H substance in Ax secretors

A

Ax RBCs

69
Q

contain A substance detectable only by agglutination/ inhibition studies using Ax RBCs as indicators

A

Ax RBCs

70
Q

Caution should be used in interpreting results of secretor studies using Ax indicator cells and anti-A, because not all Ax cells are agglutinated by anti-A.

A

Ax RBCs

71
Q

Characteristically demonstrate mixed-field agglutination with antiA and anti-A, B, but only a very small percentage of the RBCs (10% or less) agglutinate.

A
72
Q

Estimated number of A antigen sites on the few agglutinable RBCs is approximately 3500 per RBC, whereas no detectable A antigens are demonstrated on RBCs that do not agglutinate.

A
73
Q

Secretor studies detect the presence of only H substance in the saliva of Aend secretors. AntiA1 is found in some Aend sera.

A

Aend RBCs

74
Q

The phenotypes of Afinn and Abantu are considered by some investigators to represent variants of the Aend subgroup

A

Aend RBCs