ANTI GLOBULIN TESTING

Question 1

Binding site of antibodies

Answer 1

FC region

Question 2

In this test incomplete antibodies do not agglutinate in RBCs, it is also used for the detection of incomplete anti-Rh antibodies

Answer 2

AHG/Coomb’s test

Question 3

What is the principle of AHG TEST?

Answer 3

Direct agglutination reaction:
Clumping is a result of antibodies being detected

Question 4

2 types of AHG reagent

Answer 4

Polyspecific AHG-contains both anti-IgG and Anti-C
targets both IgG and Complement protein

Monospecific AHG- contains 1 antibody specificity
Targets either of the two

Question 5

What are the sources of AHG reagent?

Answer 5

Polyclonal AHG reagent- clones of plasma cells
Monoclonal AHG reagent- hybridoma technology

Question 6

Testing of Polyclonal and Monoclonal can be done simultaneously
T or F?

Answer 6

False
You have to test for Polyclonal first to determine if there is a reaction and afterwards proceeds to monoclonal for identification of specific IgG or Complement protein

Question 7

What are the cells used for Hybridoma Technology?

Answer 7

Spleen Cells- for Antibody production
Myeloma Cells- division of cells

Question 8

What culture medium is used for Hybridoma Technology?

Answer 8

HAT Medium
Hypoxanthine Aminopterin Thymidine

Question 9

Indirect Coomb’s Test happens inside or outside of the body?

Answer 9

In Vitro/Outside

Question 10

It is the In-Vivo sensitization of RBC, a positive result means that the RBC is sensitized already

Answer 10

Direct Coomb’s Test

Question 11

Sample and Coagulant used for Direct Coomb’s Test

Answer 11

3-5% RCS and EDTA

Question 12

Upon checking of results in Direct Coomb’s test, a negative result was obtained. Which component should be added to confirm a negative result.

Answer 12

Checks cell/Coomb’s control cell

Question 13

Sensitization of RBCs happen in vitro, this test checks for the unattached antibodies that are floating in the bloodstream

Answer 13

Indirect Coomb’s Test
Indirect Antiglobulin Test

Question 14

What are the factors affecting AHG Test

Answer 14

1. SERUM-TO-CELL RATIO = 40:1
2. REACTION MEDIUM (22%BSA, LISS, PEG)
3. INCUBATION TIME
4. INCUBATION TEMPERATURE = 37OC
5. SALINE FOR WASHING NSS = fresh sterile pH 7.2- 7.4
6. WASHING OF RED CELLS
7. ADDITION OF AHG
8. CENTRIFUGATION BEFORE GRADING = 3400 rpm or 500-1000 RCF for 15-20 seconds