Regulatory T cells in paraneoplastic neurological syndromes

Focusing on CD4(+)CD25(+) regulatory T lymphocytes (T-reg), we studied the gene expression of T-reg functional molecules in peripheral blood lymphocytes of patients with paraneoplastic neurological syndrome (PNS), including Lambert-Eaton myasthenic syndrome (LEMS) with small cell lung carcinoma (SCLC) and anti-Hu- or anti-Yo-antibody-positive PNS. T-reg-rich subsets were sorted from the patients' peripheral blood mononuclear cells, and the mRNA expression levels of their functional genes were measured. The expression levels of FOXP3, TGF-beta and CTLA4 mRNA in T-reg-rich subsets of PNS patients were down-regulated compared with that of SCLC patients without PNS. These results suggest that T-reg dysfunction plays a role in PNS development. (C) 2008 Elsevier B.V. All rights reserved.