Toll-like receptors 2 and 4 expression on peripheral blood lymphocytes and neutrophils of Egyptian multiple sclerosis patients

Background: Studies have just started delineating the role of Toll-like receptors (TLRs) in the pathogenesis of multiple sclerosis (MS).

Objectives: To investigate the expression of TLR-2 and TLR-4 on peripheral blood neutrophils and lymphocytes in Egyptian patients with MS, and to examine the role of TLR-2 and TLR-4 expression as a candidate biomarker for MS diagnosis.

Methods: A total of 84 patients with newly diagnosed MS and 68 healthy controls were included in this study. The expression levels of TLR-2 and TLR-4 were assessed by flow cytometry technique using appropriate monoclonal antibodies.

Results: TLR-2 demonstrated a significantly higher expression on the lymphocytes and neutrophils of patients, whereas that of TLR-4 was significantly higher only on lymphocytes than those in the control group. However, there was no significant difference between patients with relapsing remitting MS and those with secondary progressive MS in terms of TLR-2 and TLR-4 expression. The expression of TLR-2 and TLR-4 on the lymphocytes and neutrophils of patients showed no significant correlation with either the duration of the disease or disability. The sensitivity and specificity of TLR-2 expression on lymphocytes and neutrophils to diagnose MS were 73.81%, 70.59%, 69.05%, and 52.94%, respectively. The sensitivity and specificity of TLR-4 expression on lymphocytes and neutrophils were 88.10%, 79.41%, 78.57%, and 76.47%, respectively.

Conclusion: The expression of TLR-2 and TLR-4 on peripheral blood neutrophils and lymphocytes has a potential role in the pathogenesis of MS. TLR-4 expression on lymphocytes and neutrophils could be used as a potential biomarker to diagnose MS.