Tfh cells residing within the lymph node GC have since been identified as a major source of the persistent latent and productive HIV reservoir (105) due to the inaccessibility of cytotoxic CD8 T cells into B cell follicles within the GC that creates a privileged environment for HIV replication and infection of Tfh cells, the predominant population of CD4 T cells in the follicles (106, 107). Here, CD4 is linked to infection.