Flow cytometric analysis of lymphocytes in cerebrospinal fluid in patients with tick-borne encephalitis

Area of Science:

• Neuroimmunology
• Virology
• Flow Cytometry

Background:

• Tick-borne encephalitis (TBE) is a viral infection affecting the central nervous system (CNS).
• Understanding the immune response within the CNS is crucial for TBE pathogenesis.
• Cerebrospinal fluid (CSF) analysis provides a window into immune cell dynamics during CNS infections.

Purpose of the Study:

• To quantify and characterize lymphocyte subsets in the CSF of TBE patients.
• To compare CSF lymphocyte populations with peripheral blood counterparts.
• To investigate the expression of activation markers on T cells in relation to disease course.

Main Methods:

• Flow cytometry was used to analyze CSF and peripheral blood samples from 33 TBE patients.
• Lymphocyte subsets including T cells (CD3+), B cells (CD19+), and NK cells (CD3-CD56+) were quantified.
• Expression of IL-2 receptors (CD25+), transferrin receptors (CD71+), and HLA-DR molecules on T cells was assessed.

Main Results:

• T lymphocytes (CD3+) and transferrin receptor-expressing T cells (CD71+) were significantly elevated in CSF compared to peripheral blood.
• B lymphocytes (CD19+) and NK cells (CD3-CD56+) were more prevalent in peripheral blood.
• Early TBE infection showed higher HLA-DR expression on T cells, while later stages exhibited increased IL-2 receptor (CD25+) expression.

Conclusions:

• Significant disparities exist in lymphocyte subset distribution between CSF and peripheral blood in TBE patients.
• Time-dependent alterations in CSF lymphocyte subsets occur during the course of TBE infection.
• These findings enhance our understanding of CNS cellular immunopathogenesis in TBE.