IL-10 indirectly modulates functional activity of CD4⁺CD28^null T-lymphocytes through LFA-3 and HLA class II...

Area of Science:

• Immunology
• Cardiology
• Molecular Biology

Background:

• CD4+CD28null T-lymphocytes expand in chronic heart failure (CHF) patients.
• These cells produce proinflammatory cytokines, potentially driving CHF pathogenesis.
• Tumor Necrosis Factor (TNF) is implicated in CD28 loss, while Interleukin-10 (IL-10) may limit T-lymphocyte responses.

Purpose of the Study:

• To investigate the role of the IL-10/TNF ratio in modulating CD4+CD28null T-lymphocyte levels in CHF.
• To explore the in vitro effects of IL-10 on CD4+CD28null T-lymphocyte proliferation and cytokine production.

Main Methods:

• Serum IL-10 and TNF levels were measured in 65 CHF patients.
• Correlation analysis was performed between the IL-10/TNF ratio and CD4+CD28null T-lymphocyte counts.
• In vitro experiments assessed IL-10's impact on anti-CD3 stimulated T-lymphocytes and monocyte expression of HLA-DR, ICAM-1, and LFA-3.

Main Results:

• CHF patients with an IL-10/TNF ratio ≥1 exhibited significantly lower CD4+CD28null T-lymphocyte levels compared to those with a ratio <1.
• In vitro, IL-10 reduced the proliferation of CD4+CD28null T-lymphocytes stimulated with anti-CD3.
• IL-10 pre-treatment inhibited TNF production and reduced HLA class II and LFA-3 expression on monocytes, mimicking effects of blocking CD2/LFA-3 costimulation.

Conclusions:

• The IL-10/TNF ratio is a significant factor in regulating CD4+CD28null T-lymphocyte expansion in CHF.
• IL-10 exerts inhibitory effects on CD4+CD28null T-lymphocytes, potentially via modulation of HLA class II and LFA-3 expression.
• Targeting IL-10 or related pathways may offer therapeutic strategies for managing CD4+CD28null T-lymphocyte-driven inflammation in CHF.