Circulating rotavirus-specific T cells have a poor functional profile.

Area of Science:

• Immunology
• Virology
• Cellular Biology

Background:

• T cell responses are crucial for adaptive immunity against viral pathogens.
• Assessing the functional profile of T cells specific to different antigens is important for understanding immune competence.
• Rotavirus (RV) infections can impact T cell function, necessitating investigation into RV-specific T cell responses.

Purpose of the Study:

• To evaluate the frequencies and functions of circulating T cells producing key cytokines (IFN-γ, TNF-α, IL-2) after stimulation with rotavirus (RV), tetanus toxoid, and influenza antigens.
• To analyze the potential anergic state of RV-specific T cells and the effect of anergy inhibitors (rIL-2, rIL-12, DGKα-i).

Main Methods:

• Peripheral blood mononuclear cells (PBMC) from healthy adults and children were stimulated with RV, tetanus toxoid, and influenza antigens.
• Flow cytometry was used to quantify cytokine production (IFN-γ, TNF-α, IL-2) and T cell proliferation.
• RV-specific T cell anergy was assessed by antigen stimulation in the presence of rIL-2, rIL-12, or DGKα-i.

Main Results:

• RV-specific T cell responses were significantly lower in magnitude and quality compared to tetanus toxoid and influenza responses.
• RV-CD4 T cell responses were predominantly monofunctional (IFN-γ+), whereas influenza and tetanus toxoid responses included multifunctional T cells.
• Recombinant interleukin-2 (rIL-2), but not rIL-12 or DGKα-i, enhanced the frequencies of RV-specific CD4+ and CD8+ T cells producing IFN-γ and TNF-α.

Conclusions:

• Circulating T cells specific to rotavirus exhibit a relatively poor functional profile.
• The addition of rIL-2 in vitro can partially reverse the functional impairment of RV-specific T cells, suggesting a potential therapeutic avenue.