All Sample Questions

B Lymphocytes 1

Question

Vignette: A 25-year-old woman presents to her primary care physician with a 1-week history of fatigue, malaise, and high fever. She also reports having a sore throat and difficulty swallowing. On physical examination, her physician notes enlarged and tender cervical lymph nodes. A throat culture is negative for Streptococcus pyogenes. The physician decides to proceed with a Monospot test.

Question: The Monospot test used for this patient's condition detects heterophile antibodies. Which cell type is primarily responsible for the production of these antibodies?

Choices

A. B-lymphocytes

B. T-lymphocytes

C. Natural killer cells

D. Dendritic cells

E. Macrophages

Answer

A. B-lymphocytes

Explanation

The Monospot test is a rapid serologic test used to screen for infectious mononucleosis, which is most commonly caused by the Epstein-Barr virus (EBV). The test detects heterophile antibodies, which are non-specific antibodies produced by activated B-lymphocytes in response to EBV infection. These heterophile antibodies can agglutinate sheep or horse erythrocytes, a characteristic that is utilized in the Monospot test. Although T-lymphocytes are involved in the immune response to EBV, they do not produce antibodies. Natural killer cells, dendritic cells, and macrophages also play various roles in immune responses, but they do not produce antibodies.