Mangosuthu University of Technology, South Africa
Shamala Moodley is the vice chancellor of Mangosuthu University of Technology, South Africa. She is also the Head, Department of Biomedical sciences, Mangosuthu University of technology
Background: Human Leucocyte Antigen-G (HLA-G) molecules are involved in the inhibition of cell-mediated immune responses and could promote the propagation of HIV-1 infection across the placental interface thus increasing the risk of vertical transmission. Th erefore, the objective of this study was to assess whether the Major Histocompatibility Complex (MHC)-coded molecule HLA-G inhibits Natural Killer (NK) cell activity thereby, assisting viral penetration across the placental barrier in HIV- 1 positive pregnant women. Study Design and Methods: Natural Killer (CD56+) cell activity and placental HLA-G1 expression was assessed using immunohistochemistry and real-time polymerase chain reaction (RT-PCR) techniques, respectively. Studies were performed on a total of fi ft y fi ve placental samples obtained from HIV-1 infected mothers at birth. Results: Low numbers of NK cells increased risk of vertical transmission [OR=3.424 (95% CI 0.65-17.89)]. Th e risk of babies becoming infected increased by 1.3 with every 1 unit increase in HLA-G1 expression. A positive correlation was observed between mothers’ log viral load and transmission of infection to the baby (p=0.047; 95%CI 1.029-11.499). Conclusion: Low NK cell activity at the placental interface increased the risk of vertical transmission. Maternal viral load remained a strong predictor of viral transmission.