HIV infection can stimulate cellular and humoral immune responses in the body, and HIV-specific CD4+ and CD8+ T-lymphocyte immune responses can inhibit HIV replication; neutralizing antibodies can neutralize free HIV virus and HIV particles that have bound to cells but have not yet entered the cells; natural killer cells (NK) can kill and lyse HIV-infected cells through antibody-dependent cytotoxicity. Natural killer cells (NK) can kill and lyse HIV-infected cells through antibody-dependent cytotoxic effects, etc., which have an inhibitory effect on HIV replication. After the acute phase, the HIV viral load level decreases and can remain at a certain low level of replication, and the CD4+ T lymphocyte count recovers to a certain extent precisely as a result of the immune effect of HIV infection.
The immune escape mechanism of HIV is associated with high heterogeneity, selective downregulation of major histocompatibility antigens (MHC), damage to CD4+ T cells, viral escape cytotoxic lymphocyte recognition and reduced cytotoxic response function of NK cells. associated.
As CD4+ T cells are the central cells of the immune system and the main target cells of HIV infection, after HIV infection of CD4+ T cells, with the deepening of immune system damage and viral mutation of HIV, the body’s immune system eventually loses control over HIV infection, and under the action of certain factors, latent HIV is activated and replicates and spreads in large numbers, extensively destroying immune cells and other