Serology

Question 1

What are agglutination tests?

Answer 1

Used to identify antigens or specific antibodies in body fluid or secretion

Question 2

Discuss the principle for agglutination tests?

Answer 2

1. Antibodies bind to antigens on solid particles in fluid medium.
2. Antibodies cross-link the particles to form a visible clump.

Question 3

Differentiate Forward from Reverse hemagglutination.

Answer 3

Forward: Known test reagents (anti-A,B, D) added to RBCs with unknown antigens.
Reverse: Add patient’s serum to lab RBC’s; Test looks for antibodies.

Question 4

How do you detect Salmonella?

Answer 4

Direct agglutination; If patient serum has antibodies against salmonella, clumping will occur.

Question 5

How do you detect autoreactive antibodies?

Answer 5

Indirect agglutination: When the antigens or antibodies are artificially attached to the particles. Causes agglutination.

Question 6

Discuss agglutination inhibition.

Answer 6

Testing the ability to disrupt antigen/antibody interactions. Used for rubella and measles;

1. Mix serum with virus
2. Add RBCs
3. Look for agglutination. NO aggultination is a positive test.

Question 7

What is a western blot?

Answer 7

An immunoassay used to identify antigens present in low concentrations.

Question 8

Discuss Western blot testing.

Answer 8

1. Electrophoresis is used to separate proteins
2. Antigens are transferred to nitrocellulose
3. Antibodies are used to detect antigens on nitrocellulose.

Question 9

What is an elisa immunoassay?

Answer 9

Identifies specific antigens or antibodies in bodily fluid or secretion.

Question 10

Discuss Flow cytometry

Answer 10

Used to detect antigen on cells in suspension and quantify specific cells.