What type of cells do HIV primarily infect?

HIV primarily infects CD4 T cells, which are a crucial component of the adaptive immune system. These cells play a vital role in orchestrating the immune response by signaling other immune cells to respond to infections. CD4 T cells are specifically targeted by the virus because they express the CD4 molecule on their surface, which HIV uses as a primary receptor to gain entry into the cells. Upon infection, HIV can replicate within these cells, leading to cell death and a gradual decline in the immune function if left untreated. This depletion of CD4 T cells is what makes individuals susceptible to opportunistic infections and other complications commonly associated with AIDS.

Red blood cells do not have the CD4 receptor and are not part of the immune response; hence, they are not infected by HIV. Memory B cells are involved in antibody production and long-term immunity but are not the primary targets of HIV. Neutrophils, which are key players in the innate immune response, also lack CD4 receptors and are not significantly affected by the virus. Understanding this specificity helps in the development of therapies aimed at preserving CD4 T cell function and managing HIV infection.