Immune-based interventions in perinatal human immunodeficiency virus infection

Area of Science:

• Immunology
• Virology
• Pediatrics

Background:

• Nearly all new human immunodeficiency virus (HIV) infections in infants and children result from perinatal exposure (in utero, during birth, or via breastfeeding).
• The majority of vertical HIV transmission occurs around the time of delivery, influenced by maternal viral load, immune status, fetal/infant immunity, and placental integrity.

Purpose of the Study:

• To explore the role of impaired immunologic control in the pathophysiology of perinatal HIV transmission.
• To investigate potential strategies for interrupting vertical HIV transmission through immune enhancement.

Main Methods:

• Review of existing studies linking maternal factors (e.g., advanced disease, low CD4 count, antibody titers) to vertical HIV transmission risk.
• Examination of impaired cellular immune responses in HIV-exposed infants.
• Consideration of immune enhancement strategies, including hyperimmune globulin and vaccines.

Main Results:

• Advanced maternal disease and low CD4+ T-cell counts are associated with increased vertical HIV transmission.
• Low maternal antibody titers to specific HIV V3 loop epitopes may also increase transmission risk.
• Cellular immune responses, particularly cytotoxic lymphocyte development, appear compromised in HIV-exposed infants.

Conclusions:

• Impaired immunologic control is increasingly recognized as a key factor in perinatal HIV transmission.
• Enhancing maternal and infant humoral and/or cellular immunity presents a logical and potentially feasible approach to prevent vertical HIV transmission.
• Clinical trials are underway to evaluate HIV hyperimmune globulin and vaccines for pregnant women and HIV-exposed infants.