Changes in lymphocyte subpopulations and CD3+/DR+ expression in sepsis.

Area of Science:

• Immunology
• Clinical Medicine
• Flow Cytometry

Background:

• Sepsis is a life-threatening organ dysfunction caused by a dysregulated host response to infection.
• Understanding immune cell dynamics in sepsis is crucial for diagnosis and treatment.
• Previous studies noted immune alterations in surgical or trauma-induced sepsis.

Purpose of the Study:

• To quantify lymphocyte subpopulations in sepsis patients.
• To assess the expression of CD3+/HLA-DR+ on lymphocytes during sepsis.
• To compare immune profiles of sepsis patients with healthy individuals.

Main Methods:

• Prospective clinical study involving 40 sepsis patients and 34 healthy controls.
• Two-color flow cytometry was utilized for analysis.
• Evaluated lymphocyte subsets including T cells (CD3+, CD4+, CD8+), B cells, NK cells, and CD3+/HLA-DR+ expression.

Main Results:

• Septic patients exhibited significantly lower percentages and absolute numbers of total T lymphocytes and CD4 T lymphocytes compared to controls (P < 0.01).
• Absolute counts of CD8 T lymphocytes, NK cells, and CD3+/HLA-DR+ lymphocytes, along with the CD4/CD8 ratio, were also significantly decreased (P < 0.01).
• A significant increase in the percentage of B lymphocytes was observed in sepsis patients (P < 0.01).

Conclusions:

• Findings align with previous research on sepsis following surgery or trauma.
• Reduced lymphocyte subsets in non-surgical sepsis may indicate a generalized stress response.
• Elevated B lymphocyte percentages likely correlate with the bacterial cause of sepsis.