How does AIDS virus infect?

• HIV virus has gp120 (a surface protein) that has binding sites for CD4 molecule on the surface of CD4+ T cells. 
• HIV virus gp120 also is able to bind to coreceptors CCR5 and CXCR4 on the surface of CD4 T cells.  These coreceptors are invovled in allowing HIV entry into the cell.
• Individuals with homozygous mutations of CCR5 become resistant to HIV.
• Other cells that HIV infects:
• Monocytes and macrophages (serve as reservoirs of HIV and may allow entry into CNS)
• Neural cells (by two ways:  through CD4 receptors OR through receptor sites for neuroleukin.
• Microglial cells of CNS
• Dendritic cells, Langerhans cells,

Proviral DNA is integrated into the Host genome (Latent stage)... it can remain like this for a while producing low-level virion production.  However, it can be reactivated (possibly by infection of EBV or CMV).

Spread:  blood, semen, vaginal secretions, breast milk, saliva