Blood Bank - Week 1 (Ag/Ab, Antiglobulin, ABO)

Question 1

Which part of the IgG antibody allows it to cross the placenta?

Answer 1

Fc (crystallizable region)

Question 2

Naturally occuring Abs

Answer 2

Antibodies against antigens in nature that are very similar to antigens on RBC’s

Question 3

Which are the expected antibodies in blood?

Answer 3

Anti-A and anti-B

Question 4

Which antibody can have levels that fall below the detectable level?

Answer 4

Kidd’s

Question 5

What is the method used for in-vivo sensitization detection?

Answer 5

DAT (direct antiglobulin test)

Take blood sample, incubate with antibodies to human IgG and C3, look for agglutination

Question 6

What is the method used for in-vitro sensitization detection?

Answer 6

IAT (indirect antiglobulin test)

Take patient serum, add RBC’s with known antigens, incubate with antibodies to human IgG, look for agglutination

Question 7

What factors influence Ag/Ab reactions?

Answer 7

Centrifugation, Ag-Ab ratio, pH, temp

Question 8

What is in polyspecific AHG (antihuman globulin reagent)?

Answer 8

Antibodies against IgG and C3d (complement)

Question 9

What is in monospecific AHG (antihuman globulin reagent?

Answer 9

Only antibodies against IgG

Question 10

Why do we incubate RBC’s with antisera?

Answer 10

To allow time for the antibody to attach to the RBC antigen

Question 11

Why do we perform at least 3 saline washes?

Answer 11

Remove free globulin molecule

Question 12

Why do we add antiglobulin reagent?

Answer 12

To form visual RBC agglutinates in positive reactions

Question 13

Why do we centrifuge?

Answer 13

Brings cells closer together so they can agglutinate if positive

Question 14

Why do we add antibody-coated RBC’s to negative reactions?

Answer 14

To confirm washing and reagents worked correctly

Question 15

What do we do for sample with Rouleaux (too much protein in blood)?

Answer 15

Wash sample to remove protein

Question 16

If you have a positive DAT (in-vivo) what will your auto control (patient plasma and cells) be?

Answer 16

Positive

Question 17

A1 reacts with:

Answer 17

Anti-A and anti-A1, agglutinates with lectin

Question 18

A2 reacts with:

Answer 18

Anti-A only, increased reactivity with anti-H lectin

Question 19

What could cause you to suspect a patient is A2?

Answer 19

If the forward type is weaker A and the reverse is O (Anti-B and some anti-A1)

Question 20

What is the sugar of the A antigen?

Answer 20

N-acetylgalactosamine

Question 21

What is the sugar of the B antigen

Answer 21

D-galactose

Question 22

What blood can be given to Bombay patients?

Answer 22

Other Bombay blood

Question 23

What blood can be given to A2 blood?

Answer 23

A2 or O

Question 24

Rank blood types from greatest amount of H substance to least amount of H substance

Answer 24

O > A2 > B > A2B > A1 > A1B

Question 25

Why do we add clear solutions first and cells second?

Answer 25

Once you add cells it can be hard to see if you added clear solutions, so add them first to be sure

Question 26

What health conditions could cause ABO reverse discrepancies?

Answer 26

Depressed antibody production (elderly, hypogammaglobulinemia, immunodeficiency, etc)

Question 27

What health conditions could cause ABO forward discrepancies?

Answer 27

Weakly reacting/missing antigens ("acquired B" phenomenon, leukemia, Hodgkin's disease, etc)

Question 28

What is "acquired B" phenomenon?

Answer 28

Bacterial enzymes modify A sugar into sugar similar to B (acidify to see if it is true B)

Question 29

What could cause discrepancie between forward and reverse?

Answer 29

Protein/plasma abnormalities (treat by washing), cold reactive antibodies, warm autoantibodies, etc

Question 30

Rank Rh antigens from greatest immunogenicity to least

Answer 30

D > c > E > C > e

Question 31

Weiner terminology of DCe

Answer 31

R1

Question 32

Weiner terminology of DcE

Answer 32

R2

Question 33

Weiner terminology of Dce

Answer 33

R0

Question 34

Weiner terminology of DCE

Answer 34

Rz

Question 35

Weiner terminology of dce

Answer 35

r

Question 36

Weiner terminology of dCe

Answer 36

r'

Question 37

Weiner terminology of dcE

Answer 37

r"

Question 38

Weiner terminology of dCE

Answer 38

ry

Question 39

Room temp IS antibodies

Answer 39

M, N, P1, Le(a), Le(b), Lu(a) | Not clinically significant, IgM

Question 40

37C incubation antibodies

Answer 40

D, E, K | IgG, clinically significant

Question 41

Antiglobulin (AHG) phase antibodies

Answer 41

Rh, K, Duffy, Kidd, S, s, Lu(b) | IgG, clinically significant