Escape from CD8(+) T cell responses in Mamu-B*00801(+) macaques differentiates progressors from elite controllers

Area of Science:

• Immunology
• Virology
• Primatology

Background:

• Elite controllers with Human Leukocyte Antigen (HLA) class I alleles control HIV replication, implicating CD8(+) T lymphocytes.
• However, most individuals with protective HLA alleles do not control HIV, and the mechanisms remain unclear.
• Indian rhesus macaques expressing Mamu-B*00801 control Simian Immunodeficiency Virus (SIV) replication, modeling human elite control.

Purpose of the Study:

• To investigate the role of CD8(+) T lymphocytes during acute SIV infection in Mamu-B*00801(+) macaques.
• To understand how viral evolution and immune responses determine long-term viral control status.

Main Methods:

• Longitudinal monitoring of immune responses and viral evolution in SIV-infected Mamu-B*00801(+) macaques.
• Analysis of viral escape from Mamu-B*00801-restricted CD8(+) T lymphocyte responses targeting Vif and Nef.

Main Results:

• Progressor macaques, which failed to control viral replication, showed early viral escape from immunodominant CD8(+) T cell responses.
• Elite controller macaques exhibited minimal viral variation in targeted epitopes, suggesting sustained immune pressure.
• Early CD8(+) T cell escape is a key indicator of poor viral control in this model.

Conclusions:

• CD8(+) T lymphocytes play a critical role in controlling SIV replication during the acute phase of infection.
• Early viral escape from CD8(+) T cell responses dictates the inability to control viral replication.
• Understanding these early immune dynamics is vital for developing strategies to achieve viral control in HIV infection.