Trained Immunity and Susceptibility to HIV

Area of Science:

• Immunology
• Vaccinology
• Infectious Diseases

Background:

• A dual-purpose attenuated Mycobacterium tuberculosis-simian immunodeficiency virus vaccine (AMTB-SIV) was developed.
• Previous research on vaccine-induced trained immunity has shown varied effects on subsequent pathogen challenge.

Purpose of the Study:

• To investigate the impact of the AMTB-SIV vaccine on susceptibility to simian immunodeficiency virus (SIV) infection in infant macaques.
• To explore the potential role of trained immunity and CD4+ T cell activation in vaccine-induced SIV susceptibility.

Main Methods:

• Infant macaques were immunized with the AMTB-SIV vaccine.
• Immunized and non-immunized macaques were subsequently exposed orally to SIV.
• CD4+ T cell responses and susceptibility to infection were monitored.

Main Results:

• Infant macaques immunized with AMTB-SIV required fewer oral SIV exposures to become infected compared to non-immunized controls.
• The study suggests a potential link between vaccine-induced trained immunity and augmented CD4+ T cell activation.
• This activation may lead to increased susceptibility to SIV infection.

Conclusions:

• The AMTB-SIV vaccine may inadvertently enhance susceptibility to SIV infection in infant macaques.
• Trained immunity and CD4+ T cell responses could play a critical role in this phenomenon.
• Further research is needed to understand the implications for human immunodeficiency virus (HIV) vaccine development.