Oligoclonal expansion of γδT cells in cerebrospinal fluid of multiple sclerosis patients

Abstract

We have used a PCR based method to analyse TCRγ chain repertoire and clonality of γδ T cells in the CSF and blood of 11 MS patients. Samples collected from nine patients with other neurological diseases were used as a control. Five controls had central nervous system inflammation and four had non-inflammatory processes. We have observed a decreased percentage of γδ T cells expressing TCRγ with Vγ9 and Jγp fragments in the CSF samples in comparison with the blood. We did not find clonal expansion of the γ cells in any control case. Clonal expansion of γδ T cells occurred in five of 11 MS cases in the CSF but not in the blood. Two of these clones expressed TCRγ rearranged with Vγ9 and Jγ1 fragments, two others used Vγ10 and Jγp1, and one used Vγ9 and Jγp fragments. We found no correlation between clonality and clinical state of patients, duration of the disease or number of cells in CSF. Our study provides additional evidence for the possible role of the γδ T cells in the MS pathogenesis.