Things I Forget

Question 1

What concentration of rbc suspension do we use for our Abo grouping

Answer 1

3-5% suspension rbcs in saline

Question 2

How much of your reagent red cells do you add to gels?

Answer 2

50 ul reagent red cells

Question 3

How much plasma do you add to gels?

Answer 3

25ul

Question 4

What suspension are your rbc reagents for the antibody screen?

Answer 4

0.8%

Question 5

In your own words how do you carry out an antibody screen using gels

Answer 5

Get your green AHG gel

Get your pipette and pipette tips

Get your reagent rbcs, add 50ul of 0.8% suspension to the wells

Get your patient plasma/serum and add 25ul to the wells

Incubate at 37 degrees for 15 mins and centrifuge

Question 6

Define a forward group

Answer 6

Using known antiserum (eg. Anti-A, Anti-B, Anti-A,B)
to test for the presence of antigens on patient cells

Question 7

Define a reverse group

Answer 7

Using reagent red cells of a particular ABO type
(eg A cells and B cells) to confirm the presence of
appropriate ABO antibodies in a patients
Plasma/Serum

Question 8

What saline suspension of rbcs do you use for all tubes

Answer 8

3-5%

Question 9

What saline suspension of rbcs do you use when adding rbcs for the reverse group in gels

Answer 9

0.8 to 1%

Question 10

When carrying out your Rh phenotyping for patients in tube, what controls do you use?

Answer 10

You select two cells from the BioRad Screening cells as appropriate

You want a range of results between the two controls to cover your tests

Question 11

What are your controls for the 3 panel antibody screen?

Answer 11

A weak anti D
An inert AB serum

Question 12

What do you need to remember for the 3 panel antibody screen?
(4)

Answer 12

You need x2 LISS/Coombs Gels (Green lines on gel) -> one for your patient and one for your controls

You need 3 BioRad reagent cells (I, II, III)

Controls = 25ul weak anti-D or 25ul Inert AB to each reagent cell (50ul) on control gel i.e. no patient

Needs to be incubated for 15-20 mins at 37 degrees

Question 13

What do you need to remember for the ID of unexpected antibodies gels?

Answer 13

You need x2 LISS/COOmbs gel cards (green)

You need x2 Enzyme Panel - NaCl Gels (red)

You need your BioRad Antibody ID panel - untreated (white cap)

You need you BioRad antibody ID panel - papanised (red cap)

Need to add 50ul of each rbc and 25ul patient plasma to each

+ Control needed for untreated and treated panel -> 25ul weak anti-D with 50ul RhD positive cell (pick from panel)

Need to incubate at 37 degrees for 15 minute

Question 14

What is the shear plane?

Answer 14

The positive cloud surrounding the negative charge of rbcs

Question 15

What is the zeta potential?

Answer 15

Potential = difference between two charges
Zeta potential = electrical potential of the slipping plane

Question 16

Why do you need to add AHG for antibody screens?

Answer 16

IgM is able to fill the gap between rbcs and cause agglutination

IgG is unable to do these - too small

Question 17

What antigens need homozygous expression to be excluded in an antibody screen

Answer 17

MNS
Duffy
Kidd

Question 18

Papain destroys which antigens

Answer 18

MNS
DUFFY