Pathogenesis of HIV infection

摘要

The development of molecular tools to measure HIV-1 RNA in plasma has revealed the presence of high levels of virus throughout the course of HIV infection.Sustained high levels of HIV-1 in the plasma are the result of a dynamic equilibrium between continuous productionof HIV in lymphoid tissues and ocntinuous clearance of the virus by the immune system.It is estimated that up to 10 billion(10~10) particles of HIV-1 are produced and cleared daily in an infected individual.This dynamic equilibrium results in the continuous turnover of the virus population,with approximately one-half of the circulating virus being replaced with newly produced virions each day.Detailed studies of viral dynamics show that the decline in plasma HIV-1 RNA levels after initiation of potent therapy follows several distinct phases of decay.The infectivity of viral particles declines rapidly,with a half-life of 1-2 hours.