What are the two primary coreceptors utilized by HIV?

The two primary coreceptors utilized by HIV for entry into host cells are CCR5 and CXCR4. HIV primarily targets CD4 positive T cells, which serve as the main cell type for viral entry. However, the entry process also requires these coreceptors.

CCR5 is important for the initial stages of infection, particularly in the early phases of HIV transmission, as many strains of HIV use this coreceptor to infect mucosal tissues. Later in the disease, the virus may switch to using CXCR4, which is often associated with widespread disease progression and is found on activated T cells. The ability of HIV to utilize both coreceptors—understanding that CCR5 is primarily used in the acute phase and CXCR4 in the chronic phase—illustrates a crucial aspect of HIV pathogenesis and treatment considerations.

In this context, the other options do not reflect the coreceptor interactions relevant to HIV. CD4 is indeed required for the virus to attach to the host cell, but it is not classified as a coreceptor. Likewise, CXCR5 and CD26 are not utilized by HIV for entry, nor are CCR1 and CCR3, which are involved in other immune responses but do not serve the function required for HIV entry into cells. This