Medical Laboratory Technician Exam Immunology and Serology 4

Question 1

Which of the following best describes the mechanism of action of monoclonal antibodies used in immunoassays?

Accepted Answer

They are derived from a single B cell clone and bind one epitope

Answer

Monoclonal antibodies are produced by hybridomas derived from a single B cell clone and bind a single specific epitope with high specificity.

Question 2

In a sandwich ELISA, the capture antibody and detection antibody must:

Accepted Answer

Recognize different epitopes on the same antigen

Answer

Sandwich ELISA requires two antibodies recognizing non-overlapping epitopes so antigen is 'sandwiched' between capture and labeled detection antibody.

Question 3

A newborn with recurrent bacterial infections, absent tonsils, very low B cells, and very low immunoglobulins most likely has:

Accepted Answer

X-linked agammaglobulinemia (Bruton's)

Answer

X-linked agammaglobulinemia is caused by BTK gene mutation, resulting in failure of B cell maturation and absent immunoglobulins in males.

Question 4

Cold agglutinins associated with Mycoplasma pneumoniae infection react with which RBC antigen?

Accepted Answer

I antigen

Answer

Cold agglutinins from M. pneumoniae infection are IgM autoantibodies directed against the I antigen on adult red blood cells.

Question 5

In nephelometry, the measured signal is:

Accepted Answer

Light scattered at an angle from the incident beam

Answer

Nephelometry measures light scattered by antigen-antibody complexes at a fixed angle, with scatter intensity proportional to complex concentration.

Medical Laboratory Technician Exam Practice Test

Medical Laboratory Technician Exam Practice Test

Medical Laboratory Technician Exam Immunology and Serology 4