Virology USMLE Step 1 Practice Question
A 31-year-old man enrolled in an HIV drug trial receives a CCR5 antagonist. He presents with fever (38.2°C), tachycardia (102 bpm), and fatigue. Recent CD4 count is 450 cells/μL with HIV RNA of 85,000 copies/mL. Physical examination reveals no opportunistic infection signs. He denies antiretroviral medication use prior to enrollment. This CCR5-blocking intervention would most directly impair viral entry into which of the following cell types early in HIV infection?
Answer choices
- AErythrocytes
- BCD4 positive T cells and macrophagesCorrect answer
- CB lymphocytes
- DNeutrophils and eosinophils
- ENatural killer cells only
- FDendritic cells and Langerhans cells
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