Deficiency of CD8+ effector memory T cells is an early and persistent feature of multiple sclerosis

• Published in: Multiple sclerosis Vol. 20; no. 14; pp. 1825 - 1832
• Main Authors: Pender, Michael P, Csurhes, Peter A, Pfluger, Casey MM, Burrows, Scott R
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01.12.2014; Sage Publications Ltd
• Subjects: Adult; Case-Control Studies; CD4-Positive T-Lymphocytes - immunology; CD8-Positive T-Lymphocytes - immunology; Epstein-Barr virus; Female; Flow Cytometry; Herpesvirus 4, Human - immunology; Humans; Immunologic Memory - immunology; L-Selectin - immunology; Leukocyte Common Antigens - immunology; Lymphopenia - immunology; Male; Middle Aged; Multiple Sclerosis - immunology; Research Papers; T-Lymphocyte Subsets - immunology; CD62L; Multiple sclerosis; CD45RA; CD8+ T cell; Epstein–Barr virus; immunological memory
• ISSN: 1352-4585; 1477-0970; 1477-0970
• DOI: 10.1177/1352458514536252

Background: Patients with multiple sclerosis (MS) have a deficiency of circulating CD8+ T cells, which might impair control of Epstein–Barr virus (EBV) and predispose to MS by allowing EBV-infected autoreactive B cells to accumulate in the central nervous system. Based on the expression of CD45RA and CD62L, CD4+ T cells and CD8+ T cells can be subdivided into four subsets with distinct homing and functional properties, namely: naïve, central memory, effector memory (EM) and effector memory re-expressing CD45RA (EMRA) cells. Objective: Our aim was to determine which memory subsets are involved in the CD8+ T cell deficiency and how these relate to clinical course. Methods: We used flow cytometry to analyze the memory phenotypes of T cells in the blood of 118 MS patients and 112 healthy subjects. Results: MS patients had a decreased frequency of EM (CD45RA–CD62L–) and EMRA (CD45RA+CD62L–) CD8+ T cells, which was present at the onset of disease and persisted throughout the clinical course. The frequencies of CD4+ EM and EMRA T cells were normal. Conclusion: Deficiency of effector memory CD8+ T cells is an early and persistent feature of MS and might underlie the impaired CD8+ T cell control of EBV.