Subgroups, Secretors, and ABO discrepancies Flashcards
1
Q
variation in the antigen that makes it difficult for the other subgroups
A
subgroups
2
Q
Give the percentage and reaction of A antigen subgroups:
A
- A1
- 80%
- reacts wtih anti-A & anti-A1
- A2
- 20%
- reacts with anti-A
3
Q
Give weaker A subgroups
A
- A3
- An
- Al
- Aint
- Ax
- Ay
- Az
4
Q
Give B subgroups
A
- B1
- B2
- B3
- Bm
- Bw
- Bx
- Bell
5
Q
Give AB subgroups
A
- A1B
- A2B
6
Q
What are the quantitative basis to differentiate A1 & A2?
A
- antigen sites
- [α-3-N-acetyl-galactosaminyl]
7
Q
- infrequent and rare
- use anti-B and anti-A1B to differentiate
A
B antigen subgroups
8
Q
Variants of group B
A
- True B antigen
- acquired-like B antigen
9
Q
- used to differentiate variants of group B
- agglutinates red cells of true B antigens
A
Anti-B1 lectin
10
Q
Anti-B1 lectin soure
A
Bandeiraea simplicifolia
11
Q
Removal of antibody in serum
A
absorption
12
Q
Diffuses red cell to remove red cell antibodies from
solution
A
elution
13
Q
Reacts with cells derived from serum of group B and subgroups of A
A
Anti-A
14
Q
Agglutinate the red cells of subgroup A1
A
absorbed anti-A1
15
Q
Agglutinate the red cells of Ao, Am, Ax besides from regular A and B
agglutinogens
A
Anti-AB
16
Q
- Agglutinate the red cells of A1 and A1B
- Orange to yellow in color
A
Anti-A1 lectin
17
Q
Agglutinate the red cells of O and subgroup of A2
A
Anti-H lectin
18
Q
Give the source of the ff:
- anti-AB
- anti-A1 lectin
- anti-H lectin
A
- anti-AB: O serum
- anti-A1 lectin: Dolichos biflorus
- anti-H lectin: Ulex europaeus
19
Q
A1 antigen foreign substance is introduced to patient if
transfused
A
1st transfusion
20
Q
Second Transfusion
- forward typing
- A is?
- B is?
- backward typing
- A is?
- B is?
A
- forward typing
- A is (+)
- B is (-)
- backward typing
- A is (+) px’s serum has anti-A1
- B is (+) has anti-B
21
Q
- neutralize antibody in the antisera
- ABH antigens are present in body fluids
A
secretors
22
Q
Give 5 locations where secretors can be found
A
- saliva
- seminal fluid
- sweat
- breast milk
- ovarian cyst fluid
23
Q
ABH antigens are present in all organs of the body
A
Histo Blood group Antigen
24
Q
Responsible for expression of ABH antigens in body fluids
- 80% secretor
- 20% non-secretor
A
Secretor gene (FUT2)
25
Allows H gene to function in secretory cells
Secretor gene (FUT2)
26
What are the 3 genotypes (secretor & non-secretor)?
* SeSe *(secretor)*
* Sese *(secretor)*
* sese *(non-secretor)*
27
secretor of A & H substance
Sese, H, A
28
non-secretor
sese, H, A
29
non-secretor (no H gene)
\*sese, hh
30
Give the secretions of the ff blood types:
* A
* B
* AB
* O
* A: **_A & H_**
* B: **_B & H_**
* AB: **_A, B & H_**
* O: **_H_**
31
* controls the appearance of ABH antigen in body fluids
* regulates H gene activity in secretions, but not on the RBCs
Se system
32
* *does not* affect formation of ABH antigen on the red blood cell
* *does not* control the ABH transferases in hematopoietic tissue
Se gene
33
* produces **α-2-L fucosyltransferase** expressed in tissues
* utilizes type I precursors to form type 1 H determinants
Secretor H gene
34
* on erythrocyte’s membrane
* regulates production of H-antigen on erythrocytes
Zz system
35
In secretor experiment what principle is involved?
neutralization or inhibition
36
In secretor experiment, what is the positive result?
no agg'n
37
Which blood group has the greatest amount of **H antigen**?
"O"
## Footnote
\* O → A2 → B → A2B → A1 → A1B
38
first described by **Bhende** in 1952 in Bombay, India
Bombay gene
39
Give the genotype & phenotype of bombay individuals
* genotype: **_hh_**
* phenotype: **_Oh_**
40
True or False
All antigens are present in bombay gene but all antibodies are absent.
False
## Footnote
\*All **antibodies** are **present** in bombay gene but all **antigens** are **absent**.
41
* potent and active over a wide thermal range
* IgM activates complement
anti-H by Bombay
42
* benign agglutinin
* frequently seen in subgroup of A1 & A1B
anti-H as cold agglutinins
43
* anti-H by **Bombay** reacts best at what temp:
* anti-H as **cold agglutinins** reacts best at what temp:
* anti-H by **Bombay** reacts best at what temp: **_37° C_**
* anti-H as **cold agglutinins** reacts best at what temp: **_4° C_**
44
**Bombay Categories**
* hh & sese:
* Hh & sese:
* hh & Se:
* hh & sese: **_RBC H deficient & non-secretor_**
* Hh & sese: **_RBC H partially deficient & non-secretor_**
* hh & Se: **_RBC H deficient & secretor_**
45
Give the designation of the ff:
* hh & sese
* Hh & sese
* hh & Se
* **hh & sese**
* ohA
* ohB
* ohAB
* **Hh & sese**
* Ah
* Bh
* ABh
* **hh & Se**
* ohO
* ohB
* ohAB
* ohA
46
* ABH antigens are weakly expressed on red blood cells
* normal expression of ABH antigens in
secretions
RBC H deficient & secretor
hh & Se
47
ABH cannot be expressed in RBC and secretions
RBC H deficient & non-secretor
hh & sese
48
* weak expression of H gene
* A enzyme and B enzyme are affected and will be weakly expressed
RBC H partially deficient & Non-secretor
Hh & sese
49
When forward and backward typing do not agree
ABO discrepancies
50
confirmatory test of the result of forward typing
Backward typing
51
True or False
There is a discrepancy if strength of the agglutination should be 4+ or 3+ for the forward and backward typing
False
## Footnote
*\*no discrepancies*
52
Test done for weak or missing ABO antibodies
backward typing
53
detects presence or absence of antigens
forward typing
54
result of rouleaux formation
plasma/protein abnormalities
55
Identify which polyagglutination is permanent & temporary
* T polyagglutination
* Tn polyagglutination
* CAD
* T polyagglutination: **_temporary_**
* Tn polyagglutination: **_permanent_**
* CAD: **_permanent_**
56
T antigen is also known as?
* hidden antigen
* cryptic antigen
* cryptantigen
57
Give 5 conditions that give a weak or missing antibodies
1. newborns
2. elderly people
3. leukemia
4. lymphoma
5. chimerism
58
Give 3 conditions that give a weak or missing antigens
1. leukemia
2. Hodgkin's disease
3. acquired B phenomenon
59
Give 3 conditions that give plasma/protein abnormalities
1. elevated globulin level
2. Wharton's jelly
3. Plasma expanders
60
Give 2 conditions for miscellaneous abnormalities
1. cis-AB
2. polyagglutination
61
Resolve the ff discrepancies:
* weak/missing antibodies
* weak/missing antigens
* plasma/protein abnormalities
* **weak/missing antibodies**
* test against A & B
* incubate at RT for 15-30 mins
* (-): 4° C for 15-30 mins
* **weak/missing antigen**
* enhanced antisera
* incubate at RT for 15-30 mins
* (-): 4° C for 15-30 mins
* **plasma/protein abnormalities**
* wash with NSS (thrice)
62
spontaneous red cell agglutination by all sera regardless of the blood type
polyagglutination
63
Give 2 plasma expanders
* dextran
* polyvinylpyrrolidone
64
T polyagglutination is caused by what enzyme?
neuraminidase
65
* cold reactive autoantibodies
* unexpected isoagglutinins
* unexpected non-ABO alloantibodies
miscellaneous abnormalities
66
* unequal crossing over at the ABO locus
* instead of two genes being inherited, you inherit three genes
* ABO are still present
cis-AB
67
* microbial/bacterial/viruses produce enzymes that can alter the antigens
* T-transformation
T polyagglutination
68
T antigens acid
N-acetyl neuraminic acid
(NANA or sialic acid)
69
insufficient addition of sialic acid during erythrocyte maturation
Tn polyagglutination
70
* cells are agglutinable because RBCs carry large amount of Sda antigen
* inherited autosomal dominant
* shows resistance to invasion *Plasmodium falciparum*
* red cells have sialic acid
CAD
71
Give the microbially associated form of polyagglutination:
Tn
T
72
Give the microbially associated form of polyagglutination:
CAD
Tx
73
Give the microbially associated form of polyagglutination:
HEMPAS
Tk
74
Give the microbially associated form of polyagglutination:
NOR
Th
75
Give the microbially associated form of polyagglutination:
Hemoglobin M
Hyde Park
VA
