Effect of first, second, and third trimester placental factors on CD4, CCR5, and CXCR4 expression in human peripheral...

Area of Science:

• Immunology
• Virology
• Obstetrics

Background:

• Human immunodeficiency virus (HIV) vertical transmission remains a significant concern.
• Understanding the role of placental factors (PF) in modulating immune responses is crucial for preventing mother-to-child transmission.
• CD4, CCR5, and CXCR4 are key receptors involved in HIV entry into host cells.

Purpose of the Study:

• To investigate the effect of first, second, and third trimester placental factors (PF) on CD4, CCR5, and CXCR4 expression in human peripheral blood lymphocytes (PBLs).
• To explore the influence of these placental factors on the vertical transmission of human immunodeficiency virus (HIV).

Main Methods:

• Human peripheral blood mononuclear cells (PBMCs) were exposed to first, second, and third trimester PF (25% concentration) for 24 hours.
• Flow cytometry was employed to determine the expression of CD4, CCR5, and CXCR4 in PBLs.
• The percentages of CCR5(+), CXCR4(+), and CCR5(+)CXCR4(+) cells within peripheral blood CD4(+) lymphocytes were quantified.

Main Results:

• All trimester PFs significantly reduced CCR5 expression in PBLs, with first-trimester PF demonstrating higher efficacy.
• A significant decrease in the percentage of CCR5(+) and CCR5(+)CXCR4(+) cells in peripheral blood CD4(+) lymphocytes was observed in PF-treated groups compared to controls.
• The first-trimester PF group showed a more pronounced reduction in CCR5(+) and CCR5(+)CXCR4(+) cells compared to the second and third trimester groups.

Conclusions:

• Placental factors can effectively reduce CCR5 expression on human PBLs and CD4(+) lymphocytes.
• This reduction in CCR5 suggests that PF may inhibit R5-tropic HIV entry, thereby playing a vital role in preventing intrauterine HIV infection.
• The findings highlight the potential of placental factors in mitigating vertical HIV transmission.