Increased human herpesvirus-8 neutralizing response during remission from Kaposi's sarcoma

Area of Science:

• Virology
• Immunology
• Oncology

Background:

• Human herpesvirus-8 (HHV-8) is an oncogenic virus linked to Kaposi's sarcoma (KS).
• KS prevalence is significantly higher in individuals with human immunodeficiency virus-1 (HIV-1) co-infection.
• Neutralizing antibodies against HHV-8 lytic surface glycoproteins, like gpK8.1 and gHgL, are present in infected individuals.

Purpose of the Study:

• To investigate the relationship between HHV-8 antibody levels, neutralizing capacity, and KS disease status.
• To identify specific viral glycoproteins targeted by neutralizing antibodies.
• To explore the potential role of neutralizing antibodies in KS remission.

Main Methods:

• Tested 58 HHV-8-positive serum samples for gpK8.1- and gHgL-binding antibodies and in vitro HHV-8-neutralizing capacity.
• Categorized samples based on disease status: asymptomatic infection, active KS, and KS remission.
• Compared antibody levels and neutralizing capacity across disease groups and analyzed correlations.

Main Results:

• Neutralizing capacity increased with KS remission.
• Antibodies targeting gpK8.1, but not gHgL, were elevated during active disease and remission.
• Antibody levels targeting gHgL correlated with serum neutralizing response in SLK cells.

Conclusions:

• HHV-8 glycoproteins, particularly gHgL, are targets for neutralizing antibodies.
• Recovery from KS is associated with enhanced neutralizing capacity.
• Neutralizing antibodies may play a role in the resolution of Kaposi's sarcoma.