Modulation of transferrin receptor by HIV-2.

Area of Science:

• Virology
• Cell Biology
• Immunology

Background:

• Human immunodeficiency viruses (HIV-1 and HIV-2) cause AIDS but differ in disease progression and receptor usage.
• HIV-2 utilizes a broader range of chemokine receptors than HIV-1.
• The transferrin receptor (TFRC/CD71), crucial for iron uptake, is investigated for its role in viral entry.

Purpose of the Study:

• To investigate the modulation of TFRC expression by HIV-1 and HIV-2.
• To explore the role of HIV-2 Tat protein in TFRC regulation.
• To assess the impact of TFRC changes on cellular iron uptake.

Main Methods:

• Transduction of human cell lines (HEK-293T, Jurkat, THP-1) with HIV-1 and HIV-2 pseudovirions.
• Quantitative PCR and western blotting to measure TFRC mRNA and protein levels.
• Assessment of intracellular iron levels and the role of HIV-2 Tat.

Main Results:

• HIV-2, but not HIV-1, significantly upregulated TFRC mRNA in HEK-293T cells.
• HIV-2 induced varied TFRC expression changes (upregulation and downregulation) in Jurkat and THP-1 cells at mRNA and protein levels.
• HIV-2 transduction increased intracellular iron in Jurkat cells, dependent on functional HIV-2 Tat protein.

Conclusions:

• TFRC is identified as a novel, Tat-dependent host target of HIV-2.
• Findings provide insights into HIV-2's broader receptor tropism.
• The study highlights potential effects on host iron metabolism and viral tropism.