T Cell Subsets in the Germinal Center: Lessons from the Macaque Model

Area of Science:

• Immunology
• Virology
• Primate Research

Background:

• Germinal centers (GCs) are key sites for B cell maturation, requiring T cell help.
• Specialized T cells, including T follicular helper (Tfh) and regulatory T cells (Tfr), modulate GC reactions.
• GC-resident CD8+ T cells, though rare, can expand during viral infections.

Purpose of the Study:

• To review discoveries on GC-homing T cells in macaques, particularly in Simian Immunodeficiency Virus (SIV) and Simian-Human Immunodeficiency Virus (SHIV) models.
• To understand the role of follicular T cell subsets in HIV progression, viral persistence, and vaccine responses.
• To explore therapeutic strategies targeting follicular T cells for HIV vaccine enhancement and reservoir elimination.

Main Methods:

• Review of experimental studies in macaque models of SIV/SHIV infection.
• Characterization of GC-homing T cell subsets (Tfh, Tfr, CD8+ T cells) in non-human primates.
• Analysis of T cell involvement in B cell responses during HIV infection and vaccination.

Main Results:

• Macaque models provide insights into T cell dynamics within GCs during viral infections.
• Follicular T cell subsets play critical roles in HIV pathogenesis and immune responses.
• Studies highlight the potential of manipulating T cells to improve HIV vaccines and therapies.

Conclusions:

• Macaque models are valuable for studying GC-T cell interactions relevant to human HIV infection.
• Targeting follicular T cells offers promising avenues for enhancing HIV vaccine efficacy.
• Manipulating T cells may aid in the elimination of HIV reservoirs.