Boosting Immunity to HIV-Can the Virus Help?

摘要

The human immunodeficiency virus (HIV), the cause of AIDS, invades certain types of host immune cells, in particular CD4~+ T helper 1 (T_H1) lymphocytes that are progressively eliminated as the virus replicates. These CD4~+ T cells, along with CD8~+ cytotoxic T lymphocytes, are essential for mounting a coordinated immune attack against HIV In the absence of an-tiretroviral drug therapy, the intensity and diversity of CD4~+ and CD8~+ T cell responses against HIV increase as the amount of virus in the blood (viral load) decreases during primary HIV infection. Treating newly infected HIV patients with antiretroviral triple drug therapy (HAART) provides a rapid reduction in the initial burst of virus replication and helps to preserve the HIV-specific CD4~+ T_H1 cell population from rapid elimination; unfortunately, this strategy also lessens the intensity of the HTV-specific CD8~+ cytotoxic T cell response. This calls into question the actual benefit of early therapeutic intervention, which does not completely eradicate the virus and leaves the patient with an incomplete antiviral immune response.