HIV-Host Cell Interactions

Abstract

The development of antiretroviral drugs (ARVs) was a great milestone in the management of HIV infection. ARVs suppress viral activity in the host cell, thus minimizing injury to the cells and prolonging life. However, an effective treatment has remained elusive for four decades due to the successful immune evasion mechanisms of the virus. A thorough understanding of the molecular interaction of HIV with the host cell is essential in the development of both preventive and curative therapies for HIV infection. This review highlights several inherent mechanisms of HIV that promote its survival and propagation, such as the targeting of CD4⁺ lymphocytes, the downregulation of MHC class I and II, antigenic variation and an envelope complex that minimizes antibody access, and how they collaboratively render the immune system unable to mount an effective response.

Keywords: AIDS; CCR5; CD4+ T cells; CXCR4; HIV; T lymphocytes; T- cell exhaustion; cells; dendritic cells; immunity; sex.

Figure 1

The life cycle of HIV-1.The early stage begins with virus interaction with the host cell receptors (1), which causes the virus to fuse and release its viral core into the host cell’s cytoplasm (2). Following this, the core is transported across the cytoplasm (3) as reverse transcription and nuclear import start to occur (4). The viral components are brought into the nucleus at the nuclear pore, where they are localized to transcriptionally active chromatin while uncoating and reverse transcription are carried out (5). Integration follows (6); then, viral genes are transcribed (7) and translated (8) into the Gag polyproteins, which assemble (9) and localize to the host membrane, followed by the occurrence of the budding of an immature virion (10). The viral protease cleaves the Gag polyprotein into its component, functional proteins during the last stage of the HIV-1 lifecycle, known as maturation (11).

Figure 2

Toll-like receptors. Toll-like receptors act as antigen sensors for the immune system. They recognize a wide range of foreign antigens and thus help the immune system mount an appropriate response.