Medical Laboratory Technician Exam FREE Medical Laboratory Technician Immunology and Serology Questions and Answers 2

Question 1

Which immunoglobulin class is most abundant in serum and provides the majority of antibody-based immunity against invading pathogens?

Accepted Answer

IgG

Answer

IgG is the most abundant immunoglobulin in serum, comprising approximately 75-80% of total serum immunoglobulins.

Question 2

In a direct antiglobulin test (DAT), what does a positive result indicate?

Accepted Answer

Antibodies or complement are bound to the surface of red blood cells in vivo

Answer

A positive DAT indicates that antibodies or complement components have attached to red blood cells in the patient's circulation.

Question 3

Which complement pathway is activated by antigen-antibody complexes involving IgG or IgM?

Accepted Answer

Classical pathway

Answer

The classical complement pathway is initiated when C1q binds to antigen-antibody complexes containing IgG or IgM.

Question 4

A patient presents with recurrent Neisseria infections. Which complement component deficiency is most likely?

Accepted Answer

C5-C9 (membrane attack complex)

Answer

Deficiencies in terminal complement components C5-C9 are strongly associated with recurrent Neisseria infections due to impaired bactericidal activity.

Question 5

What is the principle behind nephelometry as used in clinical immunology laboratories?

Accepted Answer

Measurement of light scattered by antigen-antibody complexes in solution

Answer

Nephelometry measures the intensity of light scattered by immune complexes formed in solution to quantify specific proteins.

Medical Laboratory Technician Exam Practice Test

Medical Laboratory Technician Exam Practice Test

Medical Laboratory Technician Exam FREE Medical Laboratory Technician Immunology and Serology Questions and Answers 2