How HIV Kills Immune Cells

How HIV Kills Immune Cells

HIV infects immune cells and kills them, discovered by the scientists at the National Institute of Allergy and Infectious Diseases.  This research suggests that preserving the immune systems of HIV-infected individuals is very important. HIV causes harm to CD4+ cells (infection-fighting human immune cells) through complex processes, such as inserting its genes into cellular DNA.

It has been found that in the integration step, a cellular enzyme called DNA-dependent protein kinase (DNA-PK) becomes activated. Generally, this enzyme manages the repair of simultaneous breaks in both strands of molecules that comprise DNA.  When HIV integrates its genes into cellular DNA, single-stranded breaks occur, where viral and cellular DNA meets.

Scientists discovered DNA activates DNA-PK when attacked by HIV. DNA-PK performs an unusually destructive role, eliciting a signal that causes the CD4+ T cell to die. The cells that die are the very ones mobilized to fight the infection.

Scientists believe that these new researches suggest that it is better to treat HIV-infected individuals with drugs. These drugs help in blocking the early steps of viral replication-up to and including activation of DNA-PK. The medications also can prevent viral replication and may improve CD4+ T cell survival and immune function.