CXCR5 and infection: Taking into account that CXCR5+CD8+ T cells do not possess the same cytotoxic function than classic CD8+ T cells, it would be interesting to determine the cytotoxic or non-cytotoxic mechanisms that this population employ for the HIV control during natural infection in humans and their role in different contexts of the infection, such as acute or chronic phases, immune hyper-activation states, or in elite controllers and progressors.