In vitro infection of epidermal Langerhans cells with human immunodeficiency virus type 1 (HTLV-IIIB isolate)

Area of Science:

• Immunology
• Virology
• Dermatology

Background:

• Human epidermal Langerhans cells (LC) play a crucial role in skin immunity.
• The interaction between Langerhans cells and human immunodeficiency virus type 1 (HIV-1) is not fully understood.
• Investigating HIV-1 permissivity in LC is important for understanding viral transmission and pathogenesis.

Purpose of the Study:

• To investigate the permissivity of human epidermal Langerhans cells (LC) for in vitro infection with human immunodeficiency virus type 1 (HIV-1).
• To observe the early stages of HIV-1 infection and replication within LC.
• To assess the effect of specific treatments on viral production in infected LC.

Main Methods:

• Isolation of human epidermal Langerhans cells (LC) from normal skin via trypsinization.
• Co-culture of isolated LC with HIV-1-carrying promonocytic cells (U937).
• Observation of viral budding and release using electron microscopy.
• Treatment of infected LC with phorbol esters/bacterial lipopolysaccharide or tumor necrosis factor alpha.

Main Results:

• Electron microscopy confirmed retroviral-type budding from the LC membrane as an early sign of HIV-1 infection.
• Various stages of viral budding and release into the extracellular space were visualized.
• Treatment with phorbol esters/bacterial lipopolysaccharide or tumor necrosis factor alpha did not significantly increase viral production.

Conclusions:

• Human epidermal Langerhans cells (LC) are permissive to in vitro infection by human immunodeficiency virus type 1 (HIV-1).
• The study visualized the process of HIV-1 budding from LC membranes.
• Further research is needed to determine if infected LC can transmit the virus and how infection affects their antigen-presenting function.